318 head cleaning question

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BigBlockMopar28

BigBlockMopar28

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Alright so as some of you may have seen, the heads off of my 318 definitely need a good cleaning. Ive been told to use either diesel or degreaser to break the sludge down, i have both. Afterwords i was going to pressure wash the heads. This may be a stupid question (first time engine rebuild here) but would it hurt the rockers/ valve springs and such if i was to pressure wash the head with them in? Thanks
 
I will add that the only reason I dont just take them out in the first place is because everything in the head is in one piece and i'd rather not take the chance of messing something up during disassembly if i don't have to
 
It'll be easier to get the heads back on the engine if you remove the rocker shafts. Follow the FSM for torquing procedures and specs. You can download it here;

MyMopar - Mopar Forums & Information - Service Manuals

You don't need to remove the valves, springs, etc, but you may want to so you can check the mating surfaces and valve stem guide clearances. New valve stem seals are cheap, I'd swap in some new ones in while I was in there.

Since you have the heads off, may as well replace the 45+ year old harmonic damper, timing chain, and swap in a cam. Since you're swapping the cam (and appropriate distributor gear if needed), and get new springs. ;)

If you're doing it in the car, get some advil. Seriously.
 
Note* - when reassembling the rocker arms, there is an error in the service manuals on the torque - they should be torqued to 200 - 225 inch pounds, not 25 - 30 foot pounds or they can stretch and break...

also pay attention that are left and right, you have to get them in the proper position... Take a picture before you disassemble so you know how they go...

If you need any help, we can talk you through it...


I usually scrape the big stuff off with a scraper or flat screwdriver.... Then I hit it with a good parts cleaner, either the red CRC brake cleaner or barryman's 12 carb cleaner...
 
Berrymans is what I use, does anybody remember when it was really good? Now it is eco friendly or water based or something. Yeah Id disassemble the head down to the casting and dip all the valves, springs etc. Clean the casting, lap the valves, and new seals at a minimum.
 
If you have a lot of sludge on the heads, then likely there is a lot of sludge inside the rocker shafts. So I would be planning on pulling those off, knocking out the end caps and cleaning the shafts out and getting new end caps.

And I would not ever power wash a head without immediately pulling it all apart. Who knows what you will jam into the guides and under the rockers, and inside the rocker shafts, in addition to water and detergent and the resulting rust. And I'd bet the power wash force will wipe out the old and brittle valve stem seals and those needs to be replaced by now anyway.

BTW, if you have a lot of sludge in there, it cold have been the old Quaker State or Pennzoil oils; they had a lot of paraffin in them. But, it could also be due to a slow fuel leak from the carb or fuel pump into the crankcase. If it was a carb leak, you may have some badly worn cylinders, as a slow carb leak will repeatedly wash down the oil from the cylinder walls.
 
Update, this was awhile back for sure, before I had any clue what I was doing, and i still probably don't, but whatever lol. I think I ended up flushing the heads with diesel after letting them soak in degreaser, and shortly after removed one of the heads to check the cylinder walls and pistons on the drivers side of the block. All looked pretty good, I never oiled anything down so i'm hoping nothing has rusted while it sat, and if it has, that its not enough to require pulling the pistons to clean the walls (I have no idea how much surface rust on the walls calls for that). But i'm finally getting around to doing something with it, current plan is to rebuild the heads, replace dampener, make sure all is well with rotating assembly, and under the assumption that it is, i'll leave it together. New oil pan gasket and crank seal, timing chain, rear main, and the rest of the gaskets that it would need.
 
If you have any surface rust in the bores, then you can scotch-brite it off, then slowly rotate the engine to move the pistons up and down to push the crud to the top, and then wipe it out, and then wipe all bores over and over with ATF to clean them well. Run the scotchbrite around the bores at a sloped angle, not up and down.
 
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