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MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG TD TF 1500 - Rebuilding the engine block

I searched the archive for advice on cleaning an original XPAG block prior to commencing the rebuilding process, but nothing there that I could find. The plan is to use as much as I can from a completely assembled XPAW engine with most of the ancillaries still attached. Especially the crank, con rods and rocker gear. The XPAG has light surface rust internally and remnants of paint on the exterior, so a high pressure clean, guerni or bath in an appropriate solution, seems the best place to start. Is there a recommended DIY approach? Using diluted battery acid or caustic soda solution? I have a large gal tub that would easily accommodate the block. I'm not a chequebook restorer so would rather DIY; then spend money on quality parts like a Clive street cam or similar etc. The goal here is to start with a clean block. Expert advice welcomed. Cheers
Peter TD 5801
P Hehir

Peter

Strip the block including removal of all gallery and welsh plugs.

A couple of options to consider, a weeks soak in a molasses or white vinegar bath.

On removal high pressure rinse, immediately followed by complete drench with ATF to inhibit rust.

An engine rebuild will only be as good as how well you prep the block prior to assembly. Guarantee your result will be an engine that does not overheat.

Consider having the block machined to install the Chevy rear seal mod only solution to having a dry rear end. Also have the machining done to install a double lipped front seal.

Graeme
G Evans

I would also remove the head studs from the block.

Crack test the crank.

Fit new socket head cap screws to little end of con rods.

Take a little weight off the flywheel.

Fit new valve springs matched to your camshaft.

Balance all spinning components.

Use plenty of engine building lubricant during assembly - not oil.

Pack the oil pump with Vaseline & don't turn the crank until you are ready to check oil pressure.

Do not fit spark plugs until you see 20psi on the starter motor only.

Good Luck - they are easy engines to work on.

Tony
A L SLATTERY

Peter
Thought you already had an engine with a roller cam in your car------
With this block, if you're going to have any machining done on it at all, just leave it to the machine shop to do the machining required and then tank it and give it back ready to go-------easy as
William Revit

Hi Willy. I do indeed, but with this one I'd like to be a bit more traditional. No roller cam or lifters. Plenty of work on the head, valve seats, TD 1500 valves and springs etc. and the best of the XPAW innards. I have met many new enthusiastic pre 55's M.G. types here in Oz through TTORC, including a machinist whose skill set and mine dovetail with one another. Be dead easy to just go to some "specialist" who professes knowledge and charges like a wounded bull. But that's not my way.

Reading through the archive there are many casualties on this forum (and I'm not just talking about the victims of unscrupulous parts suppliers), who trusted the professionals and ended up with a pile of expensive junk. I guess having it cleaned wouldn't cost much but if it's something I can do, then I will. It's the "if you want it done right then do it yourself thing". I have two trades and a wide range of tools and equipment in my workshop at the rear of my home. Time isn't a consideration. In a shop, it is. I'd like to hand the machinist something that's cleaned inside and out and ready to go. I've made some amazing contacts over the past couple of months including chatting at length to an 85 year old owner who purchased his TF new! And he still drives it.

As this is my thread I will also mention that we all just missed out on a pair of original LUCAS rubber cased batteries complete with caps from this guy, by just a few weeks. He couldn't get them rebuilt for about the 10th time so they went to the crushers!

Thanks Tony. I had planned to do all of those things, except for lightening the flywheel. Still not sure about that. This gives me something to focus on while I'm not permitted to drive the 8 klms to work on the car. I do appreciate the above suggestions. Cheers
Peter TD 5801
P Hehir

Peter, you haven't even started your TD Engine and you are getting a spare engine ready!!!

Which dip stick positioon you going to use, the existing XPAW or drill through the plug for an XPAG dip stick. If you iintend to haev an XPAG dip stick, ensure you plug the XPAW hole, otherwise you will have oil all over the place when you start it up.

Remove all core plugs and cam shaft studs so block has nothing included or attached. Check the small water bypass holes behind core plug are there.

I am with Willie, if you are going to get the engine machined at some stage, get them to do an engine flush and crack test.

Have fun. Are you going to do work at home or where you have the TD garaged?

Stuart
Stuart Duncan

Peter
I wasn't suggesting not to clean it up yourself, Having worked in a machine shop it's a real pain when someone brings in a grotty job--clean is good but if it does have to go in for some machining just give it a general wash to make it clean to handle then get them to give it a good tank when they finish what they have to do
Cleaning it at home will never get it as clean as a good tanking will
What's the bore measure up like- has the rust got into it?
William Revit

I don't at all think that thoroughly cleaning a block is an "if you want it done right then do it yourself thing." A proper machine shop can do MUCH more to deep-clean a block than you can, no matter how well equipped your home workshop might be.

After I COMPLETELY strip an engine, removing all studs, the oil pump pressure-relief valve and driven gear shaft, my machine shop runs the engine through a detergent cleaner with hot water, then a more-aggressive chemical hot tank, and then an ultrasonic bath to dislodge any loose particles. Finally, the engine is run through a dedicated steel-shot tumbler. Only then do I have it, the head, crank and rods magnaflux crack-tested.

My experience is that there is usually some crud STILL left in the engine - I have found bits of core rodding still wedged in water passages from when the engine was built. When I get the engine home I run tapered brushes through all the oil passages with solvent, and the brushes do find more debris and crud to remove - they come out black.

After I have all measuring and fitting done and am ready to re-assemble the engine, I return the block to the machine shop, and have one further hot tank clean done. Only than am I satisfied that I have done all I can to prepare the block.

I would do nothing less to any engine, no matter how small the budget might be - thorough cleaning is the heart of any engine work.

Tom Lange
MGT Repair
t lange

Thanks Tom. That's sound advice. Mechanical removal of the accumulated years of rust must be a real challenge, obviously the original four part cleaning process that you describe is essential, along with the follow up work that you describe. Once I've done what I can with what I have I'll seek out a recommended shop here in Sydney, before I hand it on to the machinist. Cheers
Peter TD 5801
P Hehir

Stuart the block I'm rebuilding is an XPAG which is in the workshop at the rear of my home. The other bits are from a complete XPAW engine. Who knows how long the travel restrictions will be in place here in NSW? We're not permitted to leave home unless it's to buy food or for other essentials such as for medical reasons. So I'm unable to get to the car 8 klms away. Non essential travel can incur huge fines here. It seems more relaxed in QLD. The machinist is a retired home operator, not an engine reconditioning business. He is more than qualified however, but doesn't have the series of tanks that Tom mentions. Thanks for all the suggestions. I now have enough info to proceed as far as I'm able to under the present restrictions. Cheers
Peter TD 5801
P Hehir

Peter, While you are out and about buying ‘essentials’ call in at a tobacconist and pick up a packet of pipe cleaners. I think I managed a pretty good clean up of my block with cans of degreaser, a high pressure washer, and the pipe cleaners, before it went off to the machine shop for further treatment. They were great for checking oilways before final assembly.

If Trump can declare gunshops to be providing ‘essential services’ then surely tabacconists should be a legitimate source of essentials for a nicotine addict!

Cheers,
Chris
C I Twidle

Peter
here a couple of years ago a friend took his big Healey block into somewhere in Sydney-don't know where--Healey's are a bit prone to having porous blocks and this place does or did a loctite treatment to the block--He cleaned it as much as he could here with a pressure washer etc before he went and when he got there they said they'd vacumn clean it
Apparently it went in a large tank with a glass side and you could see the block sitting in there in the hot bath, it was in there for a while, overnight I believe, and then they hooked the vac. up to the tank, and he said he could hardly believe how much crud came gurgling out of it
Not saying you need the loctite thing done but if their cleaning tank job was available at a resonable price and you already live in Sydney it might be worth looking into
I've lost contact with him which I must address but the Healey Factory in Melb. would have put him onto it I reckon.
willy
William Revit

Thanks Willy and Chris. Be good if pipe cleaners came about a foot or two long. I'll get it as clean as I can while I'm in lockdown. Not sure just what kind of chemicals my Guerni can handle but with detergent and a diluted acid solution it should shift a fair bit of crud. I'll also look on the internet for suitable wire/phosphor bronze brushes that I can rotate on the end of a drill. The dozen or so brushes I have don't have any reach. I don't need convincing that the tank treatment is the way to go, once I've taken it as far as I can. There should still be some Sydney firms that do this kind of work. Tom's comment "thorough cleaning is the heart of any engine work" can't be argued with. Cheers
Peter TD 5801
P Hehir

Just discovered the latest in 21st century engine cleaning. No acids, no tanks, no detergents, no steel balls, caustic or hot dipping, no chemicals of any sort, just fine glass beads in a wet slurry. See https://www.redistrip.com.au/vapour-blasting. The best part of all for the budget minded is the cost - just $160! plus GST. He apparently has 3 M.G. blocks there now waiting for the process. There's a two week lead time. Why bother with the DIY and the chemical pollution involved. I'm definitely a convert! Just might be the best $160 I'll ever spend. Cheers
Peter TD 5801
P Hehir

Vapour blasting has been around for quite a while Peter, it's good for a lot of things but for an engine block with all the little hidden internal corners, it just can't do as good a job as a good tanking--externally yes, internally no----you don't have to worry about the chemicals just drop it off and pick it up --done
BUT- You do need to have a good measure and check session first, no use getting it all special and clean and then finding it needs boring or the tunnel doing or something
William Revit

Peter


Before embarking on your $160 block clean inspect a finished product. I am suspicious that only external surfaces are cleaned with this process (check their site images), I cant see how the block galleries are going to get sufficient treatment to remove crud.
G Evans

Yep
When I said drop it off and pick it up I meant at a good chemical bath not at the vapour blasters

Any pro engine builder would shudder at vapour blasting the insides of a block
You need to stick to the tried and tested methods used by pro engine builders and machine shops

Wash it clean
Measure and check and check and check
Decide on your spec
Machine as required
Tank it
Recheck it
Do your mock up and measure
Remachine as required
Retank it
Assemble

I'm more interested to know why you are doing a new engine when you have the original in the car with it's new roller cam etc and were ready to start it up here a week or so ago
Has something drastic happened---?
And what machinery has your retired machinist got to do the job
William Revit

Willy I'll get in touch with you off line and answer all of your questions there. Fact is I'm itching to get over to the car now that I'm able to move around reasonably well after the op, but legally I can't leave the house. So I'm doing what I can here, which isn't much.. Except for the research needed to prepare a spare engine from the stash of parts I have here. I just hope I've made the right decision re the cam in the car, (which has always been playing on my mind), but more on that off line. Just finished compiling the copy for the April issue from an overabundance of riches. It goes to the editor on Wednesday. Contributions from all over Australia. It should be a cracker! Cheers
Peter TD 5801
P Hehir

I put together a TD for my wife with blower and 3.9 MGB for highway cruising. On a hot summer day at a steady 80mph, the coolant temp could run 230F, consistently.

That made me study the cooling system. The best modification was to have a modern "furnace soldered" radiator core installed in the radiator. Wonderful.

A more insignificant operation was to grind the water inlet and outlet for the coolant passage on the side of the block. Obviously, they're only accessible with the core plugs out. The blocks had a multitude of cores assembled in production and there wasn't much attention to detail. It only took a couple of minutes to reach in with a steel grinding burr to hog the cast metal out that impinged into the holes and then a grinding stone to smooth out the edges to reduce unnecessary restrictions.

The camera could not focus worth a darn, but I'll show the best "before" and "after" shots. It looks like we can attach more than 1 image at a time now. It probably doesn't enhance cooing by 1% but it made me feel "cool!"





JIM N

As is the case with most things, the more information you gather the less you can be certain of. Unfortunately I've not been able to find a business in Sydney that follows the detergent, immersion, tank, bath etc. method described above, which I'm certain works. The business mentioned https://www.redistrip.com.au/vapour-blasting, gave me the numbers of two M.G. restoration businesses here in Sydney who use their services. I contacted them both today, one asked me to leave a message, the other couldn't speak highly enough of the process. He did add that there would still be some work to do.

I spoke to a third that was listed as a specialist M.G. Sydney firm on the BBS contact page, who recommended the tank method, but couldn't provide me with the name of such a business.

Nice work Jim. I'm seeking the sort of camera that can peer into the water jackets and provide a clear image suitable for producing a video of the interior of an XPAG block, one that could then be posted onto You Tube. My die grinder wont reach very far so I'm also looking on the internet for a suitable extension. Metabo make one that is 1.8 m long and is very expensive, as well as being totally unsuitable due to its length. I think they also make a 300 mm extension, but it's fairly rigid. The research continues. It keeps me entertained while I'm stuck here at home. Cheers
Peter TD 5801
P Hehir

For those who have their heads into IT and such could you please express an opinion on the suitability of this device for use on an engine block that is siting on the bench? https://www.ebay.com.au/itm/New-10M-Endoscope-Borescope-Wireless-6LED-Inspections-Camera-for-Android-PC/133184671793?epid=25034521504&hash=item1f026cd031:g:t8cAAOSwje5cqu-- Would this permit a reasonable quality internal block inspection of the hidden areas of the water jackets? It mentions a USB so I guess that means I'd be able to plug it into my PC and view the video? It's certainly cheap enough. Cheers
Peter TD 5801
P Hehir

Peter,

I thing that is likely not a recording device so any image captured would need to be viewed real time on your Android phone screen. The ad does mention iOS so they may have an Apple iPhone version. It seem cheap, but I wonder if the quality is there. Personally, I have an endoscope, but it has a built-in monitor and cost me US$79 at Home Depot. Others range from $99 and up.
Lew Palmer

I have a similar one I got off eBay a bout 2 years ago. I have not used it on the car yet. I have used it to look for wires behind the dry wall. Its ok. will probably do the job. its field of view is limited and pointing it where you want to look may be difficult. But for the price, it's acceptable.

Jim B.
JA Benjamin

I have a similar device that communicates with my iphone6. I used it to see the innards of my pedal box. Worked fine. Images stored in iphone. Well worth the price ~$25. Bud
Bud Krueger

Similar endoscope. But focus is not accurate. Light is not powerfull enough.
I also had to build a angled mirror to view the cylinder walls.
But worth the price.

Laurent.
LC Laurent31

See Brake/Clutch Interference in Pedal Box in the archives from 2 years ago. Bud
Bud Krueger

An update on Redi Strip. They also chemically dip cast iron blocks. Problem solved. Cheers
Peter TD 5801
P Hehir

Now you're talking, do that and then have a real good look at it checking threads ,cracks etc, then you can move on --
William Revit

Does working on your own car constitute work? If so I can drop the block off. Cheers
Peter TD 5801
P Hehir

Moving on to the next step, https://www.knowyourparts.com/technical-resources/engine/installing-cylinder-sleeves/, this link provides some very useful information in relation to sleeving a block. Providing the existing pistons and rods are serviceable and reliability rather than increased performance though a bigger bore is the goal, then this may well be the best way to proceed. That is, matching the sleeves to the existing pistons rather than re-boring the block and then finding pistons to suit. Makes economic sense to me, particularly if using components from a 4/44, with its 100 ton crank and rods made of the same quality steel. I remain deeply suspicious of the quality of modern components, especially those that come out of SE Asia for T Types, and sold by some of the major suppliers. Far too many items have proven to be absolute rubbish! Cheers
Peter TD 5801
P Hehir

You'll need to copy and paste the link to open it. Don't ask me why... I hate computers. Cheers
Peter TD 5801
P Hehir

Peter
The thing with sleeves though is the cost
The sleeves themselves aren't too bad, but you're looking at the price of a rebore to fit them then a hone and all to fit your probably worn out 2nd hand pistons that you have to buy rings for anyway-
Easier/cheaper to just rebore and get a new set of pistons/rings unless of course the bore is perfect which if it's been rusty I doubt will be the case
William Revit

Thanks Willy. Obviously there is a bit of crystal ball gazing here. Depending on condition, I'll be in the hands of the machinist and will follow his recommendation. An engine reconditioning shop would be the really expensive way to proceed, but I'm fortunate to be able to do some deals involving swaps and so things should work out much cheaper. The engine in my car was kept under cover for well over 45 years with oil in the bores and it took a bit to get it to move. But it was pristine when we lifted the head. I'm hoping the 4/44 will be the same, making all of the components re-usable. I am replacing the cam in the back up engine with a Clive street cam though. Cheers
Peter TD 5801
P Hehir

Clive knows his stuff, you're on a winner there,I've been dealing with him since the old days at Wade (that's probably why he moved ha ha)
What grind is the cam, regrind or billet
You can't get a very big grind onto a std T type cam but for a street cam you'd be ok
If you're using your old followers ,don't forget to send them to him as well to get ground if they're ok and don't show any signs of going through the hardening
On the rebore subject, a straight rebore and hone is a relatively inexpensive job at a reco place as they will have the gear set up to do it
The last 4 cylinder block I had done about a month ago was $270 and that included Chemical tank clean, surface grind the bottom of the block parallel to the crank tunnel,bore and hone and a thorough pressure wash and blow out, might be mate's rates , don't know
Had one similar just before that though but without the bottom machine and that was $240
It's a good idea to measure up to see if the bottom gasket face is parallel to the crank depending how the block mounts in the boring machine, some square up off the crank tunnel and some off the bottom face of the block, you need the bores dead square to the crank
willy
William Revit

Hi Willy. I'll get back to you with more detail off line. I'd hate to be again accused of "chat" :-). I do look forward to your insightful observations and your positive and helpful comments. Cheers
Peter TD 5801
P Hehir

Question for the brains trust. What would cause the base of a block to become unparalleled to the crank tunnel. Is the suggestion that the error exists from time of manufacture?

If I was decking the bottom of the block I would believe it prudent to do the top also as this is often the cause of head gasket failure. This is the area that is under heat stress.

Graeme
G Evans

Graeme
I don't want to get into an engine building school here but to answer your question---briefy -
There is always the chance that something wasn't machined correctly right from the start, and given the age of these engines you never know what could have been done to them-- The crank tunnel may have been machined a bit out from new or another possible is the sump gasket face may have been machined crooked--A few minuites checking is all a part of a thorough rebuild----When a block goes in for a rebore there are 2 ways of mounting it up, best is off the mains tunnel then the bores will be square to the crank and if the bottom surface is a touch out of true it won't effect the result--but if the block is mounted using the bottom surface then the bores will be cut square to that and the crank could be anywhere, probably quite ok but measuring will be the only way to know
Also the bottom deck needs to be square to the crank if the block is going to have the top deck machined (if mounting the block in the machine on the bottom deck face)otherwise the top deck could be machined out of parallel to the crank---
Normally any amount of out of line would be minimal but if it's going to be machined, why not do it right- I usually do a mock assembly before machining top decks anyway and then this allows for acurate deck height measurements that can be fiddled for an good result when machining
An example of this was a very expensive fully machined V8 block I got from the US, on one side it was almost spot on with .003" clearance deck height as ordered but the other side was .003" at one end and .018" at the other and had to be fixed up, and that was from one of the most respected engine block manufacturers about------it pays to check
measure, measure, measure
Another issue is that because of the age of these engines, if they've been rebored previously they were probably done using one of the older boring bars that bolted to the top of the block--If these aren't set up right or if the deck surface wasn't true or clean the bores could be anywhere
Hope that answers your question
willy
William Revit

Peter, don't stop "chatting." Some of us learn something new with just about every "chat." Jud
J K Chapin

Can anyone identify this dipstick? Currently on EBay. The part number is shown. T Type? Early TD? Late TD? Cheers
Peter TD 5801

P Hehir

Thanks Jud. The attached M.G. Car Company bulletin (note the dots), I must have downloaded from E Bay, as it has a huge number accompanying it as the descriptor. It's nice to know that even the factory got it wrong sometimes. When rebuilding the early TD block I'd like to be sure that I not only have the correct dipstick, but also the correct guide tube. The part # 24408 is adjacent to the one on the pic in the previous post. See both pics. Cheers
Peter TD 5801

P Hehir

Peter, later model XPAG as installed in MG Y, as installed in my Y Tourer's exchange engine.

From "Let their be Ys" by David Lawrence - "From XPAG/SC/13404, a longer dipstick, number 24407, was introduced. This dipstick was 16 1/4 inches (41.4cm) in length, and was used in conjunction with a longer guide tube, of 4 1/4 inches (11 cm) visible length."

Also "According to the Parts List, the longer dipstick and guide tube were specified fo the left hand drive "Y/T" from the beginning of production."

My engine was out a dipstick tube. I have purchased a new tube, but how do I compress one end to fit into the block?

cheers & stay safe
Stuart
Stuart Duncan

I have purchased a new tube, but how do I compress one end to fit into the block?

Immerse in dry ice and methylated spirits.
Jim B.
JA Benjamin

G'day Stuart. Seems the Service Bulletin answers your question but the sequence of numbers worries me somewhat, if only because 07 precedes 08? Could David Lawrence possibly have got it wrong? Cheers
Peter TD 5801
P Hehir

Jim, thanks for the dry ice tip. I should have thought of that.
Peter, part #24407 - dip stick, #24408 - tube, seems logical to me. The earlier dipstick was part # 24188.
Stuart
Stuart Duncan

I'm still struggling with the numbers Stuart. The early engines had - or should have had - the correct tube (and some of them did), which according to the M.G. bulletin was 24408. It seems logical therefore that the dipstick that went with this early tube would be numbered either one before or one after the tube #. That would make the 24407 the right dipstick to partner the early TD and probably the TC, would it not? The bulletin suggests that somebody on the line stuffed up and got into the habit of fitting the incorrect tube. Not everybody, probably just one the guy; and it took the factory quite a while to figure this out. Cheers
Peter TD 5801
P Hehir

Peter,
David Lawrence also states further down the page #72 & on #87.
(NB. There was no change of dipstick or guide tube at engine number XPAG/SC2/17020, as is sometimes mentioned in other publications.)

My thinking is parts 24407/08 which are the longer dipstick and associated tube were used from XPAG/SC2/ 13404, but as you state an employee may have been installing a wrong tube. (This error was found and corrected at SC/17020 and TD/10900 and the Info sheet issued to make sure mechanics had the correct length of tube showing.)

Stuart
Stuart Duncan

I am still of the opinion that the info in the M.G. Service Information Sheet No 86 dated 1st October 1951 - see copy above - and the details provided subsequently by David Lawrence, are at loggerheads. Be that as it may. Wiser heads than mine need to sort that one out. My money is on #86, even though he was a bumbling idiot!

Moving on, David Twist from University Motors states in one of his terrific You Tube videos that engines always stop at one of two points - the same point, (points) - that are exactly 180 degrees apart. Maybe because this is perhaps where the combustion and compression strokes cancel each other out? Whatever the reason, this useful piece of information suggests that the worn ring gear can be relocated 90 degrees, so that a "brand new" section of the flywheel ring gear engages with the starter motor Bendix drive. Step one would be to mark the existing relationship. I'm sure that somewhere in the archive, this has been covered many times. My guess is that heat and cold are involved. Is there a thread with a decent explanation of an idiot proof approach to this task? If so, what is the title?

Would a propane torch (LPG) provide enough heat? Do we need oxy to achieve this task or could the whole caboodle be placed on a bed of coals and the ring gear then just drops off? Would ice packs on the flywheel provide sufficient cooling? Re-installation would definitely involve the hot/cold approach. (The oven and the freezer while the boss is out shopping for essentials would do nicely). How to ensure that the relocated ring gear ends up flat and true to the perimeter of the flywheel? Could 1/2" thick glass handle the heat or do we need a thick steel plate bench top? Burning questions indeed... Cheers
Peter TD 5801
P Hehir

I have never tried to relocate a ring gear - replacements have been available and cheap enough to not bother trying to salvage the old one.

That said, if you support the flywheel by the ring gear only (fabricate a stand), you might be able to heat the ring gear with a propane/oxy enough to expand it and allow gravity to separate/drop the flywheel when the ring gear has expanded enough.

I have a few spare old flywheels so might give it a go in lockdown in the next year or so if I run out of other MG jobs in the garage.

Tony
The Classic Workshop
A L SLATTERY

Tony whether to replace or relocate an old, NOS or new from an unknown country of origin, whose metal is equally an unknown, the process is the same. Anyone done this? The WSM indicates this is doable, although surprisingly really tight tolerances are mentioned, within 0.005", so a VERY flat bench is in order... 120 teeth sound right for an early TD? Cheers
Peter TD 5801
P Hehir

I removed mine cold by just tapping it from the flywheel with a big hammer and a block of wood, going from one side to the other little by little, and did no harm to either part. It was badly worn, so I replaced it with new from B&G. Put back on by heating gently and dropping over the cold flywheel. Still there and working fine.
Dave H
Dave Hill

Most important: Do not accidentally hit the lip of the flywheel just behind the ring gear. It is thin and sadly I know it will break. George
George Butz III

Probably easier to buy a used flywheel with a ring gear, $50-70 at flea markets.

Peter
P G Gilvarry

The problem with a used flywheel is just that, it's used. The idea is to rotate the unused/unworn section through 90 degrees so that the unused section comes into play and engages with the Bendix drive; and that can only be achieved by removing and replacing the ring gear. John Twist mentions this in one of his you Tube videos. I had hoped that there would be a T Type John Twist archive on the internet, but almost all of the stuff he's posted is for the later vehicles. Cheers
Peter TD 5801
P Hehir

Assuming it is damaged of course, I saw 2 at the last auto flea market that had no damage to the teeth at all. The flywheels themselves were a little rusty, but the lightening process means it needs to go to the machine shop and that will be cured there.

The guy I was with races T series, he bought both. We then saw one more at another booth with no visible damage.

Over 50 years of English Motors I have never replaced a ring gear or had any indication that I should. The starters have worked, unless Lucas gremlins got involved.

Peter
P G Gilvarry

Just found this on You Tube. https://www.youtube.com/watch?v=j_sgiTa3gew. Now as I don't have oxy, the oven/fridge approach should work, should it not? However is there a seat for the ring gear to drop into? I don't have one handy to check. I don't remember seeing one. If there was, then the "out of round" clearance caution wouldn't be mentioned in the WSM? Cheers
Peter 5801
P Hehir

Peter

From the Aussie bush mechanic.

Removal of a ring gear using a standard propane gas torch will prove difficult as the flame temperature will require a long exposure time to obtain sufficient expansion for the gear to release. This is the reason oxy is used the flame temperature is so much higher so the heat is more localised to the gear only and there is less heat soak into the fly wheel. You would probably get away with a MAP torch available from a good hardware store.

Fitment of the gear should be viable by heating with the propane torch as the heat will only be applied to the gear only. I would still claim the deep freezer to place the fly wheel in over night.

If you dont have a flat thick steel sheet.

A little innovation to get the gear concentrically flat on ring gear would be use your spare engine head suitably chocked on the bench to produce a flat surface. Rotation of the fly wheel through 90 degrees would be necessary to confirm it is correct for the full circumference.
G Evans

Thanks Graeme. I Googled but couldn't get any info on one of the yet to be answered questions i.e. "How many teeth on a TD ring gear?" This has been answered by someone who is no longer with us. TTORC member Harry Darke from QLD has made available his father Brian's 2 volume work on TCs'. This arrived in the mail this morning, as a copy was purchased for the use of the club. We have Harry's authorisation to post Brian's technical pieces in upcoming issues of the bi-monthly magazine. We'll spread them out over the next few years as there is great information there. Copies are available to TTORC members for $40 AU for the 2 volumes.

In the section on the Engine and Gearbox, Brian answers my question. The TC has 120 flywheel teeth and the starter 9 and the TD has 93 teeth and the starter 10. I had a look at some used original flywheels yesterday and couldn't get the same result twice. They were almost certainly TC as the results I got were 118, 117 and 119. An overall diameter and a clear pic of both sides would also help, but given the number of marques and models likely to be encountered at swap meets, who knows what you're possibly buying? Cheers
Peter TD 5801
P Hehir

20 cents worth
Why bother rotating a ringgear that's stuffed anyway--get a new one
Easiest way to get them off is check which way the ringgear sits and memorize that or write it down then cut between 2 teeth with a hacksaw right down as close to the flywheel as possible then get a chisel in the slot and a good whack and the ringgear will open up then it can be removed by hand and placed in the bin-where it belongs
Reassembly
I've only ever frozen alloy flywheels steel or cast wheels don't really need freezing just cool, run the hose on them for a bit
Sit the flywheel on the ground facing the way up that the ringgear has to enter from
Sit the ringgear on a couple of bricks with your 2 pairs of multi grips and a hammer and punch ready
Put some oil on the ringgear and with the gastorch go round and round getting it nice and hot, -when the oil has all dried off she's ready, grab each side with the grips and sit the ring gear on then lightly go round and round with the punch tapping the ringgear against the shelf on the flywheel to make sure it sits right down--As the ring cools you will hear a more solid sound from the punch as the ringgear grips up, check that it's right down all round and quickly tap if it needs 'adjusting'
let it cool--job done
I doubt a propane torch would get it hot enough unless you have a fairly heavy duty nozzle, gas is the go with a decent sized tip, I use the cutting tip to get some good heat
William Revit

"The TC has 120 flywheel teeth and the starter 9 and the TD has 93 teeth and the starter 10."

Seems that this info is not correct. Should be the other way around. TC had 93 teeth. TD both early and late had 120. The TC and TD flywheel had a different diameter and was also different to look at. Seems that the best way to heat a ring gear was to use a gas ring so as to heat the entire ring evenly, looking to avoid heating the flywheel itself. Cooling the flywheel seems to be acceptable practice. I've had plenty of research material sent offline, so I'll sort the wheat from the chaff and end up hopefully distilling something close to the truth.

P.S. Graeme I do know the guru of which you speak and I was on the phone to him when your email arrived. We first met when I was at Williamtown not long after I purchased the TD in 1969 and I communicate with him whenever I really need to. He's as keen to see TD 5801 back on the road as I am. You could say that he has a paternal interest, but he'd hate me saying that, as he's only 7 years older than I am! :-) Cheers
Peter TD 5801
P Hehir

Peter
Just to be clear-
In my last entry here I referred to using gas to heat the ringgear ,,I'm meaning Oxy/Acetylene as the gas usually used in most automotive workshops
Also I see no need to freeze a flywheel, it's not going to shrink apart from a few thou---The only reason I would freeze an alloy f/wheel is to help reduce the amount of heat transfer into the f/wheel when the hot ring is fitted to him not a sizing thing
William Revit

Understood Willy. The gas ring was a special bit of kit to ensure even and focused heating all the way around the ring gear; and this piece of info arrived of line from a guy who has huge experience in the restoration of T Types here in NSW. The link to the video on You Tube shows a guy heating flywheel ring gear with oxy. I knew that's what you meant. The cold treatment does serve two purposes though, one to minimise heat loss to the flywheel, as you have stated and the other to provide some shrinkage, albeit just a few thou. But every little bit helps. I wonder if a domestic oven turned up full bore for a couple of hours would get the new ring gear hot enough? Looks like I'll have to use a TC flywheel with buggered teeth so I get it cheap and source the early TD 120 tooth ring gear from a reputable supplier. Anybody know of one? :-) And don't say you know who... Cheers
Peter TD 5801
P Hehir

Does anyone in Sydney or nearby have a TC flywheel (10 3/8") with a 120 tooth ring gear that they're willing to part with? Cheers
Peter TD 5801
P Hehir

Is SE Qld too far away ? - $50+freight.

Image attached - ring gear is good (120 teeth).

Tony
The Classic Workshop

A L SLATTERY

Let me get back to you Tony. I have a possible on Sunday and another on Tuesday. If neither pans out I'll be in touch. Cheers
Peter TD 5801
P Hehir

Tony can you post a couple of close ups of the two worn sections of the teeth please? These few teeth will be 180 degrees apart on the ring gear. It looks as though it should clean up petty well with a wet blast. Cheers
Peter TD 5801
P Hehir

Hi Tony. No luck here so far. Can you contact me offline. pjbm at bigpond dot com Cheers
Peter TD 5801
P Hehir

Thanks Tony. One more item ticked off the list. I have also just located a 7 1/4" pressure plate, driven plate and thrust bearing, all NOS. Been a good few days. Thanks to all who've helped on this thread. I now have the original worked head (TF 1500 valves and springs, shaved and ported) from the guy who owned my car in 1962, a Clive street cam, a pair of rare TD/C 4031 carbies and all the gear I need to rebuild the standby engine. As this thread is now getting a bit too long, I'll let it quietly slip away. Cheers
Peter TD 5801.
P Hehir

This thread was discussed between 05/04/2020 and 22/04/2020

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