Oil leak I cannot find 500t

Do you know for a fact,Barry, that the all stud are good? I've had to helicoil a couple of head studs on my ES2 which would not tighten and caused leaks.

Could one of the stud's threaded holes in the crankcase have broken through and the oil coming up the threads?

Could it be coming from the pressure feed to the rear of the cylinder wall? Finding a way out up a stud?

Air movement will automatically push the oil to the rear, and if it is clean itâs not easy to see where it comes from, one other place to check is the rocker oil feed banjo.

dan

Hi Barry, what colour is the oil? If black, it is coming from cylinder blow by and running down the stud todribble outon the case. Been there, done that.

Did you use after market cylinder head nuts? I once had a problem where the after market sleeve type nuts did not pull down on the head because the threads did not reach all the way into the nuts. It would torque down tight but onto the threads only. I had to run a 26tpi tap down the inside of the nut. Result, no more head leaks.

Hi Barry,

I think Michael Rettie might be on the right lines with the rear cylinder oil feed. I have a 500T Wellworthy aluminium barrel and it doesNOT have the oil feed holein it. I don't know if the earlier sand-cast barrels have one or not. I think there may have been too much oil getting in the cylinder when the engine was used at low speed in trials ?? If this is the case, you can either drill the hole by copying a standard cast-iron barrel or cut a relief groove in the inside neck of the cases so the oil will just run down onto the con-rod. Boo's suggestion also needs checking, and if you have the later head bolts they extend through the head so may catch the top fin of the barrel. I think you will need a top-end strip at least to check it out fully.

Regards, Richard.

Just a suggestion. Clean, and de-grease, the head area. When dry, coat with talcum powder (does not need to be scented!). Go for a run and stop every few miles, you may see where the leak originates. Fixing it is the next problem!