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MG TD TF 1500 - Leak around distributor

I have a small leak that I thought came from the rod cover. However, it appears to come from the distributer. Anyone who has experience from that and would it be advisable to place an O-ring or silicone under the distributer? There is no oil in the distributor itself.
Y Strom

I have tried to solve the same type of leak. I had a groove for an O ring machined in the distributor but the O ring got sliced as it passed the bolt/cotter hole. The O ring was meant to stop oil lower than the retaining bolt/cotter. Next time I think I will have a groove machined right at the top of the dizzy so the O ring only just engages in the block. I guess there is still a chance oil might weep from the dizzy retaining bolt, but that should be very minor.

I am guessing that crank-case pressure could cause or amplify such a leak. Mine was in a race engine which has done a lot of work.

Bob Schapel
R L Schapel

Very interesting

How deep was the grove and what was the diameter of the O-ring? As I had tightened the bolt rater loosely, oil might have come out that way. It has now been tightened and I will test it today if weather permits. May be a bit of sealant should be applied on the washer. But with that tight oil may instead creep up and require an O-ring as you have proposed.

It took me some time before I discovered that it was not the rod cover that leaked.
Y Strom

I wonder why some of these leak and others don't? I guess I'm fortunate as mine has never leaked. Maybe I shouldn't brag. PJ
PJ Jennings

I'm with you, PJ. Mine hasn't either, nor have I ever worked on one that did. Bud
Bud Krueger

I think it was probably about a 1.5mm (1/16") O ring. I just asked the lathe man to make a groove deep enough to suit.

I agree with PJ and Bud. Only some seem to leak. It could be crankcase pressure as I mentioned before. It could also be that some dizzys seem to be sloppier in the block. If there is a vibration in the engine, perhaps the dizzy vibrates and "pumps" a bit of oil out. I know the dizzy that leaked for me had all of the above ... a loose fit in the block, the engine had done a lot of work and it was revved to 6,500.

Mine was the early bolt type. There shouldn't be any vibration/pumping action with the later cotter type fixing. I am not referring to a major leak, just an annoying little trickle of a few drops after each race.

Bob Schapel
R L Schapel

Thanks Bob

Applied a thin layer of silicon on the washer and tightened the bolt, so now after a 30 km drive it is dry around the distributor. After the modification of the Moss seal rear end leaked one drop in 30 min. after stop and front was dry.
Y Strom

It looks like I am one of the "leakers" as against those who are lucky enough to have a dry joint.

So this topic is of major interest to me. As an original and only owner of my TF, I have experienced this problem from new, despite rebuilding the engine 4 times, the leakage at the base of the distributor persists, and continues to be an annoyance. I have tried putting a paper gasket at the base, but that didn't work.

I'd be afraid to install an o-ring on the flat surface for fear of altering the interference of the gear on the camshaft.

Would love to hear from someone who solved the problem.

I don't have a spare distributor to try the o-ring on the shaft. At this time of the year, I don't want to take my TF out of service.

Gord Clark
Rockburn, Qué.
Gord Clark

This thread was discussed between 02/08/2017 and 13/08/2017

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