Cleaning pistons and heads - what is the best way?

After chasing an oil leak from an oil cooler seal, i got bored so i thought i'd clean up my engine which i have never stripped down since owning.

I found a bit of carbon build up on my pistons (a couple of millimeters thick!) and heads, and would like to remove it to check for damage so what is the best, safest way without paying someone to do it? Valves will still be attached to the heads.

I've read oven cleaner, diesel, carb cleaner, brake cleaner, metho, etc, but will any of these damage the parts? I've also attached pics so if you see anything unusal in them let me know.

Cylinder 3 & 4 head




Piston 3


Piston 4


Pushrods - notice on 2nd from left there is a mark, this can be felt when i run my finger across it. What could this be from and should i repalce them?

if your not getting a valve grind etc DONT clean any thing.

ian.mezz wrote:if your not getting a valve grind etc DONT clean any thing.

Not even the pistons? Could you explain why that is?

Does everything look okay so far? How about that marked pushrod?

you can clean it with a piece of alluminium sheet nuthing to hard so u dont scratch the surfaces

good way to raise the compression, filling the head with carbon and baked on crap 😉 put on some new aftermarket heads while it's apart, great chance to play with it! The pushrod looks like it's been rubbing somewhere, maybe one of the pushrod tubes was bent for a while, or it was off its rocker and rolling about in there for a while (or maybe on a previous motor.. these things have chequered and interesting pasts). Worth replacing if you plan on reiability, depends on how deep the mark is and how hard you're pushing the rods... I'd replace it.

shokwave2 wrote:

ian.mezz wrote:if your not getting a valve grind etc DONT clean any thing.

Not even the pistons? Could you explain why that is?

Does everything look okay so far? How about that marked pushrod?

cause you just don't do it, you don't pull motors apart to clean them , you pull them apart to recondition them.🤪

Fair enough. I just thought a build-up of carbon in various areas may have affected my motor.

So in other words pistons, cylinders and heads must be all recondtioned together?

shokwave2 wrote:Fair enough. I just thought a build-up of carbon in various areas may have affected my motor.

So in other words pistons, cylinders and heads must be all recondtioned together?

Are you going to re ring it? If you are I suggest you also go the rest of the way as the extra load is then transferred to the next weakest point which will be the bearings.