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MG TD TF 1500 - Sump woes

As you know from another thread I sanded the flange of the sump just enough to remove all the cavities. When I had the engine rebuilt I put in a new billet crank. The combination of the two is a problem. When I put the assembly together and start to tighten up the bolts the new crank lobes start to hit the sump . I cannot imagine how close they came before I sanded the flange. I did not sand excessively, just enough to remove the cavities.
I have put blueing inside the sump and will try to identify the exact interference. One thought is to grind out a small notch In the sump to give me clearance. I will be mindful not to take enough to compromise the strength of the sump.
I also discovered this second problem. The threaded bolt hole in the timing cover that holds the front of the sump in place is stripped. One hole that goes through to the inside of the timing chain cover had a helicoil but the helicoil stripped out of the hole. It needs to be redrilled and tapped for a larger size .
The alternative would be to drill and helicoil for the next larger size bolt.
I am dealing with a sump and timing chain cover of unknown history. All of these fixes might work but I think I would rather get some new parts.
Does anyone know of or have a sump and or a timing chain cover available for sale?
M Resnicoff

I find it hard to believe that sanding til shiny removed that much material.

Methinks a bit of light work on that shield with a ball peen hammer will suffice.

---- or maybe a thicker gasket.
MAndrus

M,
Have your machinist remove a bit of steel from the outside high points of the crank lobes. It shouldn't be a problem. I had his done (the lobes were actually "knifed") to the MGA 1800 crank as part of a larger lightening/balancing procedure. You're taking a chance removing oil sump material.
How about using a thicker pan gasket?
Good luck,
Tyler
C.T. Irwin

Mort,

Brown and Gammons sell new sumps. As you can imagine there are not cheap. They have a four hole oil pick up pipe flange, that's not a problem but it means that you will need to plug the two unused holes.

John
J Scragg

Mort, is that with a sump gasket in place? Bud
Bud Krueger

I assume you mean the crank webs are hitting the tray bolted inside the sump, as the only place they are likely to hit the sump would be on the sump/gasket/block interface, but you do not say the webs also hit the block. Thus I agree with what Tyler has implied - the crank webs project too far, so must be machined back, and then the crank rebalanced.
Regarding the stripped hole in the timing chain cover, I had a similar problem with three tapped holes at the rear of the sump (a common problem). I had the bosses ground away to the central holes, and then rebuilt with weld - by a skilled welder, not me. I then had to carefully file flat the rear flange face, and then drill and tap new 8x1mm holes, using the bellhousing to fix the correct positions. One hole in the chain cover could be dealt with in this way.
R A WILSON

The problem I would worry about is thinning the sump flange itself. They aren't strong to begin with. At this point I would use a thicker gasket, or double up the usual one. This may create a leak at the rear cork seal but some extra sealant there should take care of that.
Steve Simmons

Good grief! Is it hitting the sump or the tin tray? I'd imagine you could eek out a little more clearance with the tray.
Be well,
David
D. Sander

Suggest finding out exactly where the crank is touching. It could be the metal baffle, or just a tiny spot on the sump itself. A different or new sump may have the same problem. No way your sanding caused it. Best bet is to have the stripped hole welded up, then drilled/tapped. George
George Butz

The threads in the timing covers always strip out. They are soft aluminum, and when people take bolts in and out without cleaning them, the threads get chewed to pieces. Always use CLEAN screws at this location.

I wouldn't weld it, the soft alloy may warp and cause bigger problems. I've used thread repair inserts on these covers in the past and it works a treat. Better than new, because you now have stainless steel threads that will last forever. Just be sure to get the insert straight when you drill and tap.

This is what it should look like when it's done...

Steve Simmons

There was an article in Totally T-Type or somewhere recently about a new production forged crank hitting the block I think in a P-series motor. May or may not be relevant to your issue, but at least that crank had bigger/wider balance weights than the original. Steve is right that if not done correctly it can warp. There was one guy in town years ago that did motorcycle cases, and he was an artist. Aluminum also tricky to tap- I think we used kerosene for a lubricant. George
George Butz

Do not try to use Helicoils in the soft aluminum sump and timinc chain cover. They are prone to pulling out. What I have used VERY successfully is a product called a Keensert. It is a hardened steel insert which is threaded and locked into the aluminum. They use a standard thread size and pitch on the outside so you don't need a special drill and tap to install them. Both SAE and Metric thread sizes are available, including M8x1.0. The last time I ordered some I got them from MSC Industrial Supply.
You will never regret using them and they will last forever, despite multiple fastening and unfastening.

http://www.specialty-fasteners.co.uk/products/threaded-fasteners-thread-locking/keensert-inserts/item/metric-heavy-duty-series-keensert-m8-x-100-non-internal-thread-locking
LPalmer

With due respect, I doubt a helicoil would ever pull out of the timing cover if done properly. First of all, those bolts are not supposed to be torqued that hard. Second, the hold through the pan is (or should be) too small for the helicoil to go through with the bolt in place. If you're tearing helicoils out then either the outside threads are not correct for the helicoil or the bolt is being seriously over-tightened and probably would have ripped the original threads out as well.

I've used Keenserts many times for structural work and for head studs where some dummy ground out the bolt and the hole was too big for any other type of insert. They do work very well, providing you have enough material to use them. The hole has to be drilled larger than for a traditional helicoil type repair. Very strong though, I agree.
Steve Simmons

I like the look of the Keenserts - I might have considered them. Anyway, when my welding was done the sump was preheated for several hours before the welding started. I did notice that even for the bosses that were not repaired, the innermost ends of the threads were in a better condition. Thus I replaced all the bolts with longer bolts, thus more thread, to use the full lengths of all the threaded bosses. I would suggest this if you have the chain cover welded.
R A WILSON

First, I want to thank everybody for their contributions.
Next, if you are going to read further in this post try to refrain from using the words like, stupid, idiot, amateur etc. Because I have already used them all.

So here is the story:
I put blueing all over the inside of the sump and slowly tightened down a few bolts until I could feel a scraping when I rotated the flywheel. I continued to let it scrape to be sure to get an impression in the blueing. Upon disassembly I could find no marks in the blueing. Then I realized where the problem was.

About five years ago when I installed an oil drip pan at the bottom of the bell housing I added two holes to promote drainage. Last week when I was cleaning the sump, I decided to add another tickler cotter pin to the middle hole. I did not add a cotter pin to the third hole because it was directly under the flywheel and there would be interference. After installing the sump I could not see behind the flywheel and did not realize how close the eyelet of the cotter pin was to flywheel. As it turns out, when I tightened the bolts I reduced the gap between that cotter pin and the flywheel to zero. This is what locked up the rotation of the engine.

I repaired the striped threads in the timing chain cover, with and Australian product called "Fix-A-Thred". It is just another version of a helicoil. It works quite well and easily took 19 foot pounds when tested.

Well, since you have read this far you are entitled to call me any of the above names you wish.


M Resnicoff

Mort,
I would say you are more than happy to have found that-well done! Anything else could have proved to be a major headache.

Regards
Declan
D Burns

Hooray!! Well done, Mort. Bud
Bud Krueger

Mort, the word 'meticulous' comes to mind. The guy that abuses people has been removed from the BBS under all of his six guises. (The worry is that he'll probably be back with another phony moniker, new location & email address). Glad that you sorted the problem. Thanks for sharing. Cheers
Peter TD 5801
P Hehir

Happy ending :-)
L E D LaVerne

Glad to hear all ended well! I could write a short novel about all the mechanical things I have messed up over the years. Maybe we should start a thread about that? We have all learned a lot from this thread too. George
George Butz

We've all been and done something like that. Congratulations on solving it. I learned plenty just watching this conversation.
Dave H
Dave Hill

Panic over, but surprised that three holes are needed to drain the flywheel cavity.
R A WILSON

As is always the case, start with the basics and work up in level of difficulty from there.
MAndrus

This thread was discussed between 16/02/2017 and 17/02/2017

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