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MG TD TF 1500 - XPEG head gasket

18 months ago we were renewing the valve seals on a friends TF 1500 with the head in place using compressed air,we found air tracking from 1 to 2 and 3 to 4 ( 2 to 3 OK. On removing the head we could see the blow-by. Head and block cleaned and reassembled with new gasket. The head was torqued with a calibrated wrench and twice more after running.
Last week while doing a blow by test we found it doing it again.
The head and block have less than 0.001" warp.
Can anybody suggest what is going on?
Ray TF 2884
Ray Lee

IMO it is caused by inaudible detonation, too much ignition advance and ot to high Compression ratio. The inaudible detonation causes the shifter rattle under acceleration. Higher compression ratios need a camshaft with a longer duration. Manly Ford has the BEST custom head gaskets, with copper fire rings, for T types to reduce the possibility of compression leakage between cylinders!
And I now have is stock custom T type Teflon Positive stop valve stem seals.

Len Fanelli

Ray, If your sure the head/block surfaces are straight, I would suspect the studs or nuts threads are stretching on original parts. If you haven't disassembled the head yet, I would retorque the nuts using a "click" type torque wrench and see how much more the nuts turn. Retightening the head might even temporarily correct the problem if the gasket hasn't completely failed. However, I have been using the ARP brand improved studs (from Tom Lange) on my engines and I was amazed at the obvious difference they make while torqueing the nuts. There is crisp positive click when torqueing them rather than the feeling they might not reach the correct torque without failing on original ones.
Richard Cameron

From curiosity, is the block casting number AEF117, and the head casting number AEF118. Also, what torque do you tighten the cylinder head nuts to.
R WILSON

Ray is talking about my TF1500. I confirm engine casting is AEF117 and head is AEF118, both being original to the car.
N D Wallace

What type and brand of gasket did you use? I have seen a couple unbranded copper gaskets that were not the best quality. If it was copper, did you use a copper spray gasket material? Could be combination of things. George
George Butz III

Also found no oil shrouds in the springs (original "O" ring seals). I presume the 1500 still had them?
Funnily enough my spare engine ( Wolseley 4/44) did not have them and this was well before lip seals arrived on the scene.
Ray
Ray Lee

forget the last post, they were there.
Ray
Ray Lee

I would tend to agree with Rich Cameron as noted above: assuming your head and block are flat, head studs and/or nuts are the most likely source of your problem.

Speaking immodestly, I have dealt with probably 20 owners who contacted me to inquire why they keep blowing head gaskets. After installing a set of my ARP head studs and nuts, I have not had a single return or complaint of further head gasket problems. This is due both to the superior materials of my head studs and also because my studs can be torqued to a higher value than the originals (the originals and most replacements from the usual sources are relatively soft, weak, and stretch over time). Racers use my head studs and nuts with complete confidence.

Even though I seldom feel the need to recommend re-surfacing the block, I always suggest going over the surface of the block with a small whetstone to remove the burr left by the old head studs. I have seen some burrs that would prevent a new head gasket from seating perfectly, but this does not apply, of course, to leakage between cylinders.

See mgtrepair.net

Tom Lange
MGT Repair
t lange

This thread was discussed between 25/01/2019 and 26/01/2019

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