Hot Rods Inside my 8ba Flathead

Hi hamber, opened my 8ba flathead that was running very bad, very fast overheating, white smog, oil everywhere, took some pics to show you the inside near valves... What you think about?

 

Couple things, must not be rebuilt, no adjustable valves. Also looks like it was running with a weak spark because of the carbon on the pistons and valves. Still might be a good runner though. What about cylinder wear?

 

Valves are hollow adjustable with isky springs…..cylinders looks good but, looking in some pistons i can see the upper ring clearly…..

 

That engine has serious excess carbon in it. Either from running rich, idling for long periods of time or burning oil and a severe possibility of all three.

By how much of the top of the rings you can see between the piston top it has a lot of cylinder wear. Maybe having been ringed a time or two without being bored.
A bigger problem is that detonation has eaten away the top lip of the cylinder wall pretty badly. Either from bad timing bad gas or lugging it down in too high of a gear instead of shifting down.


Back in the 50's and early 60's these engines seldom went over 60K without needing a ring and valve job and less was common.
Going back an looking at the tops of the pistons that detonation may have happened in one of the engine's earlier lives as the piston should be burned up as bad or worse than the cylinder wall. I'm thinking maybe 30 years ago someone did a quick and nasty piston swap after burning up one or more pistons.

At any rate that engine is Plum as in Plum worn out.

 

Looking on the pistons,i think in half of circle area i can see about 1mm of ring….cylinders are 83mm large...about 3,26inch.....i read on some pistons are market 0.825

 

When I lightened up the photo you can see that the piston top isn't burned up on the edge as you would expect when looking at the cylinder wall.

In the other photo you can see that the compression ring is stuck in the piston and not making any contact with the cylinder wall (orange arrow) and you can see the expender for the oil ring (blue arrow) . I'm amazed that that engine ran at all.

 

Time to bore it…change valve seats …..and adjust carburation

 

That's just carbon buildup at the top edge of the cylinder, not detonation eating away at it. It just looks like an older engine that might need a bore, some new pistons, and rings.