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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 - Head Gasket

Since I am going to be pulling the head off my early TD I wanted to have a head gasket on hand.
Looking for suggestions on where to purchase and which would be the best choice of material.

As I recall it has the elongated water holes.
Is there a different gasket from Moss vs. Abingdon vs. FTFO etc?
Mort
Mort Resnicoff (50 TD-Mobius)

Probably not. I buy the gaskets from Moss, and have been very satisfied. I pull one or two heads a year for people. Pick up a rocker cover gasket and the gasket for the water pump, the tappet chest (it will get destroyed in pulling the head) and the back of the head as well.
Dave Braun

Little British Car Company can provide it cheaper, from Moss.

www.lbcarco.com/

I'm not going to say which outfit it was, but someone sent my a new head gasket, FOLDED IN HALF! They did send a replacement.
JIM NORTHRUP SR

The NOS gaskets are better than the Moss jobs. I don't now what Abingdon carries. I got some NOS ones from here a couple of years ago. They went to basically Ebay sales but I haven't noticed them at all lately. But you might want to send them an inquiry.

http://gallery.sportsandclassics.com/products/
L E D LaVerne

Dave Braun,
The head was rebuilt about a year and a half ago. I have no problem with it. The reason I am pulling the head is to replace the rings and hone the cylinders(blow-by). I plan on doing it with the engine in the car. I mention all this because of your comments on the other gaskets.
I will leave the thermostat in place. I will leave the rear plate in place. I installed Tom Lange's silicone gaskets on the side (tappet) cover and the valve cover and plan on reusing them.
Do you see any problems with this plan?
Thanks,
Mort
Mort Resnicoff (50 TD-Mobius)

Gonna be real difficult to get the rods out without pulling the crank....but it can be done ..I think. But then you have the crap dropping down on the crank journals and even if covered most likely on the inside of the block when you hone Mort. Just my two cents.
L E D LaVerne

Mort. laverne is damnd right , DON'T hone cylinders with the crank in. Go for the extra mile otherwise and most likely you have to walk the extra mile twice
plus the extra cost.

Gerard
Gerard Hengeveld

You could try a trick I've seen done, not on a T.

Find the right sized plastic funnel that can be maneuvered to the cylinder base. Stuff paper towels to hold it in place and catch anything that gets by. All the solvent, metal and abrasive can be channeled out without running on the bearings. Wrap the journal first with electrician's tape to seal the oil hole.

Don't go too deep, just break the glaze up where the rings actually ride. It doesn't take much, just quick up and down motion to create a cross hatch to seat the rings. Use a flex type glaze breaker, not stones.

Since you can't really get soap and water in to wash the cylinder, use engine oil after getting all you can get with solvent, it seems to float out dirt the solvent leaves behind.
J E Carroll

I'm replacing crank & cam with an engine with just a few thousand miles since last overhaul and expect to use the same rings & bearings.

Are you replacing rings or reusing the old ones?

Make sure to slip the rings into the bore and measure the ring gap!

One other thing to check is the rings spring out larger than bore. I recall some mighty thin rings in the one I'm pulling apart which remind me of thin Honda rings. I've found over and over again, when I get these Honda that have overheated, the rings yield, have no spring and don't seal worth a darn, even with tight end gap. The overheated engines roll so free and easy, but with new rings and honing, the resistance is back along with compression.
JIM NORTHRUP SR

LaVerne & Jim,
Thanks. I am going to try with the engine in. Wish me luck.

Jim & Jim,
I will find a way to keep everything clean. Since I have a lot of blow-by, I suspect at least a new set of rings is due. I'll know more when I open it up.

I welcome all suggestions for replacement rings.

Thanks,
Mort
Mort Resnicoff (50 TD-Mobius)

I had some custom composite head gaskets manufactured in several thicknesses (to accommodate excessively shaved heads). I'll post a photo later if you're interested....
Rob Edwards

Mort, the silicon gaskets should stand up quite well to your plan.
Dave Braun

Mort - my silicone gaskets will be fine; just remove any stray, old adhesive and re-apply.

I don't think I would do it your way; pulling the engine is really not that big a deal, and is much better all in all. You can clean the entire engine, work on it with total confidence, and with total access.

I have a fondness for Deves rings, but I understand others have their favorites, as well.

Tom Lange
MGT Repair
t lange

Mort,
Do Keep us posted. I have exactly the same problem with blow-by. I thought at first it was the head but it wasn't as it is completely refurbished with new valves and guides.
Declan
Declan Burns

You guys are really getting to me. Pulling the engine is now under consideration.

Rob, Any info on your head gaskets would be appreciated. Photos, source, price, etc.

Tom Lange, Will the rods, head studs and nuts stand up to re-use?

Mort
Mort Resnicoff (50 TD-Mobius)

Mort,

If you're warming up to pull the engine, well, it's probably the best way but it'll lead to lots of "might as wells", you know, might as well replace this or that.

I have done rings in place successfully albeit not on a T and not with the funnel trick I only saw relatively recently. Some were on cars when I was a kid and others on tractors where the incentive is that you have to split the machine in half to get the engine out, a real PITA. I never really worried too much about abrasive getting in the main bearings as the shop rags and paper towels seemed to catch the slurry and I just flushed the heck out of everything afterwards. I really don't see how anything can get in the bearings as the clearance is really tight and nothing is forcing it in. As soon as there's oil pressure it's getting flushed away by oil. The worst I can see happening is that any miniscule amount of bad stuff might go through the pump but then it goes directly through a full flow oil filter.

I wish you the best of luck whichever way you go.

Jim



J E Carroll

Mort,
Just my 2 cents worth, but I've done rings, bearings & honing on many engines in place and never had any issues.
JIM
JIM NORTHRUP SR

Will the big end fit when you try and pull the piston out thru the top? I don't think you can get em out thru to bottom end without pulling the crank and if you have to do that it is easier to pull the motor and do it on the engine stands.
Tom Maine

Tom, they will not fit through the bore so you won't get them out from the top. However, by judicious rotation of the crankshaft it is quite possible to remove the rod/piston from the bottom with the crankshaft in situ. Bud
Bud Krueger

I think I will pull the head and drop the pan. Then I will make the decision based on what I find.
Once again thank you all for you experiential (?) advice.
Mort
Mort Resnicoff (50 TD-Mobius)

Mort,
This is a reasonable plan. Once the pistons are out (make sure to number them 1-4) check the cylinders for wear. If they are not perfectly circular they will need to be bored over. You will also have to remove any ridge on the top of the cylinders, or you will immediately break your new rings.
When installing everything, make sure to use Tom's pinch pin bolt and connecting rod bolts. Especially with a super charger you don't want the whole thing to come apart on you.
I think you will find that your rings may be broken, or at the very least have become stuck in the pistons and have lost their flex.
Keep us posted, remember, you have to have this done by Middlebury in June.
-David
D. Sander

Thanks Bud, I was unsure of whether or not the pistons could come out with the crank in. That said, how do you get a ring compressor in there with the crank in?
Tom Maine

One more suggestion to add to your confusion- you might check around your area and see if someone shotpeens rods. I plan on getting a set done soon. Good, cheap insurance against throwing a rod (worst disaster that can and does occur).
JIM NORTHRUP SR

Tom, I don't think you can do that. That's why we do the 'shove the unringed piston up through the cylinder and then ring it trick'. Bud
Bud Krueger

Tom & Bud yes it can be done, there is a chamfer at the bottom of the bore, which compresses the rings, as the piston is pushed into the bore, a little help may be needed using finger nails. When the block is bored over .060" some of the chamfer may be gone.
Torque pinch bolts to no more than 25 '/#,
do this while the piston pin is holding the assembly, if doing this with the rod in a vise, you will bend the rod.
Len Fanelli

VEERY INTERESTING.
Tom Maine

On a +.030 TC I was able to simply push the pistons up from the bottom with no spring compressor. I would suspect you may want to pull the pistons out through the bottom, inspect and remove the rings, and measure the bores. If you decide to just ridge ream the top, and deglaze the walls you can push the pistons up through the bottom, sans the rings and then install the new rings with the pistons proud of the deck. You can use a conventional ring compressor and push the rings down in to the bore. Remember the stager the ring gaps, 33' for three rings.
I suspect with the amount of blow by you mention, your rings are either broken, stuck or both. If the engine has been excessively overheated, the rings may be scorched and have lost their tensile strength, or "spring"
-David
D. Sander

David, to get the degree symbol (°) just hold down the ALT key while you enter 248. When you release the ALT key the ° appears like magic. Bud
(I don't know if it works on Apples/MACs)
Bud Krueger

Bud, no "alt" key on my iPad...but thanks for the tip :-).
-David
D. Sander

Thanks Bud, now all I have to do is remember it!

To all, when using a ring compressor, above the block,
tighten the ratchet on the tool, tap it down square or flush with the block, then tighten again.
Tap the piston down with the handle end of a hammer,
as soon as the piston skirt clears the tool, tighten it again, as the ring land area is a smaller diameter than the skirt, again make sure the tool is flush with the block by tapping it down again, and tighten tool again! This is when rings can be broken! Use plenty of motor oil. Use plastic tubing on the rod bolts to prevent damage to the crank journals.....
Len Fanelli

Here's a photo of one of the gaskets I had made. It's a steel-core composite material with steel fire rings and copper water passage rings. I've got one installed in my engine and it's doing great!

Rob Edwards

Rob,

Who made those for you?

Gene
Gene Gillam

I've got an acquaintance who makes gaskets and has done some other custom work for me
Rob Edwards

This thread was discussed between 27/11/2013 and 01/12/2013

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