Weak #6 cylinder

[40Coupe]

Originally Posted by JWL

Yes, remove the radiator. Yes, leave the trans. Yes, remove the fan from the crank. About 6 or 8 inches will give enough clearance and twisting angle to remove. I always bailing wire or strap the trans up to maintain its position in relation to the frame before removing engine.

I don't know about a stumpfy?

Yes, those look like mushroom valves. No, those do not look like stock valve springs. Look much stronger than stock.

I would like to see the bottom of the loose tappet and the coordinating cam lobe.

Thanks...I assume removing all the springs is first order, lifters, remove cam then last is removal of split bushings/guides is last- maybe I'll leave that to the machine shop...after reading all the stories here....of course that may be expensive. I'll post some more pics as I go.

Originally Posted by Ross F-1

The clean edge around that piston (no carbon) is a classic indication of oil past the rings.

Interesting..thanks- I would probably have tried just repairing the one valve but car wasn't reliable with constant fouling of plugs.

Originally Posted by Kurt in NJ

It's time to push out the pistons, it looks like the lower cyl in the picture that the top compression ring is broken---the cyl by the blue dipstick shows a good shadow that is even all around(as much as the picture shows), the bottom cyl shows ring contact in just little streaks ---most likely from the ends of broken ring pieces ---if that is also the low compression cyl most likely that is a factor in the low compression

Bad valve is #6 so lower piston is 5 and 7,8 are above. No honing marks in cylinder bore so any damage may have been from previous rings. 5,7,8 compression was some of the best! But..yes appears an overbore is in order...currently .125 over from what Dad had told me.