The Stovebolt Site Forums The Shop Area Engine Shop 235- cleaning block and cylinders

1959 Apache 235.
this is my first try at taking the engine apart to freshen it up. Having the head reworked by pros and need suggestions as to the best way to clean the block top and cylinders. Having never done this before, i don't want to get the wrong liquid on the rings or damage the internals with grit etc.. where would i go to find the basics? any tricks also would be helpful as well as any "make sure you don't do this or that".
thanks so much for all your help!!

Oldtruckspapa

Depends on if it's still in the truck or how much of the rest of the engine is still attached. I have steam cleaned ( really hot water ) long blocks inside and out then oiled them up before any rust could form. These were really dirty inside so it was the quickest and easies way to clean them without tearing them apart. At a bare minimum, you need to pull the sheet metal pieces ( side cover and oil pan ) and clean out what you can with brushes and scrapers using your choice of solvents. Everyone has their preferred cleaner to use, mine is high pressure hot water and Castrol degreaser.
Any cleaning solvent you use will run down the cylinder walls and collect at the top rings when cleaning the piston tops. Soft wire brushes and compressed air will minimize the crud collecting at the rings. If you choose to go with a liquid cleaner, flush the cylinder walls and oil afterwards, another reason to pull the sheet metal. Engines are really tough, it takes a really big mistake to hurt one. Some degreasers are hard on aluminum and bearing material if left to long, Castol being one of them, so don't leave them soaking to long. The old method was to use gasoline, brushes, scrapers, and compressed air.

How did you steam clean?

Just for clarity, "best way to clean the block top and cylinders" means the crankshaft and other engine parts are still attached.
If so, clean nothing except the top of the block. Put rags and such in the cylinders to catch falling particles.
There is usually carbon or combustion residue that fills in the spaces around the old head gasket.
This you want to clean off without scratching the machined surface of the block. The surface needs to be flat.
Afterwards you can remove the rags and vacuum out any particles remaining.
Optionally, after cleaning the top and if you have easy access, pull the oil pan and give it a good cleaning. Install a new oil pan gasket.
After running the engine for a while, change the oil again.

thanks guys, the remainder of the engine is still in the truck. I'll start the cleaning process tomorrow, Lord willing. there are a lot of opinions on the best way to do this it seems. Really appreciate your time and responses. will report back with results in a few weeks!!

thanks again,

Oldtruckspapa

Papa, if you for any reason decide to remove the oil pan and clean out as has been mentioned, please do not try to push the pistons up and out from the bottom. There will be a wear ridge at the top of each cylinder. You can feel it with your fingernail or maybe with only your fingertip. If you push the pistons up and out, the piston rings will catch on that ridge and can be broken if forced...and it doesn't take as much effort as you might think. If you feel compelled to remove the pistons this way, you'll need to get a ridge reamer to cut that ridge off first. I only mention it because you've mentioned this is you first time and I've seen friends (with whom this information wasn't shared) make this mistake. Also, you can use an old vacuum cleaner to suck debris out of cylinders if need be. Good luck.

Or use the best vacuum in the house and hide the evidence from your wife.

It was a very common procedure when I started making a little pocket change as a part time mechanic in the late 1950's and early 60's to do an "in the frame" engine rebuild- - - -ream the ring ridge, hone the cylinders, replace rings and sometimes connecting rod bearings (or adjust the clearance on Babbit rods), regrind the valves, and reassemble everything. Getting the cylinders cleaned up after the honing job was the biggest challenge. That kind of overhaul was usually good for about 30K miles or so.
Jerry

The power washer I use has a temp setting that can be adjusted for cool, warm or hot, I turn it all the way up. The engines I have washed out were on stands, crank, rods, pistons, and camshaft still in the block. I had little money to spend, this was the quickest and easiest way to get them clean, just add new gaskets and get them on the road or track. I never had one good bad because it was washed out.

Millions of engines over the years have been cleaned and overhauled in frame style. Years back, my dad drove seven of kids to my uncles house 3 hours away, we played for a day and half while he and the uncle overhauled the wagons engine. He drove us all home in the same wagon Sunday afternoon so he could get back to work on time Monday. The garage they worked in had a dirt floor!

I have done what HRL is describing, valve job, new bearings, new rings and re assemble. It was a pretty common thing back in the dark ages. it worked well

Joe, at least the floor was dirt- - - -not the middle run of a barn with a "fertilizer" floor. I've repaired a few trucks and tractors that way, with nothing but layers of cardboard between me and the organic stuff!
Jerry

Papa, Did you do a compression test before you tore the motor down?

Is low compression why you sent the head out? Was the engine using oil previous to teardown? All of these questions bear on what you should do next. These truck engines were made of pretty tough stuff, forged steel crank, hard cast-iron blocks, replaceable valve guides, valve rotators on the truck engines, molly top rings; and the bearings are the same size as the old spray-oiler engines, that is, big and long lived. All this is to say that these engines respond well to an in-frame overhaul and if the bores aren't too worn can run a very long time. With the head off you are roughly half way there. If you have the time, do a little checking and consider doing more than the head if desirable.

The weak link in the chain, in my opinion is the valves which don't get adjusted often enough, work tight and burn. You've addressed that possibility. The next weak link is piston rings damaged by dust entering from the crankcase vent system (pre-PCV) or running without an air cleaner, which back in the day many of us would-be hot rodders discarded as unneeded junk just to hear those three Stromberg 97s howl at full throttle. Have a close look at the cylinder bores are they scratched, is the rigde at the top noticeable? While you're cleaning, scrape the carbon off the top of a piston and look for a number stamped on the piston top. If there is none it'll be a standard bore, meaning the engine has not been rebored and new pistons not installed. If there is a number, it'll be something like 020 or 040, which means the engine has been rebuilt at some time.

If the engine has been maintained with regular oil changes, etc., the crank is likely still round though maybe a couple thousandths worn. GM used to sell bearings 0.002" undersize to accommodate just such a situation. Today, you'd have to shim the bearings using tapered shim stock if you can find that. But maybe the bearings are just fine and if it's burning a little oil, a ring job would put you back on the road in fine style. A set of rings is about $100 these days and rod bearings another $60-75, mains are similarly priced and luckily for you, should you opt to change them, are pinned to the caps not the block as 1955 and earlier were.

I have been into two of these engines recently and am beginning reassembly today. Both engines were taken out of service due to a burnt piston, number 1 in one case and number 6 in the other. The bores were not damaged. The engine that came out of my truck had over two hundred thousand miles on it and the cylinder ridges just barely catch my finger nail. It had been rebored 0.040 in 1973 and had been run without an air cleaner for an unknown time before that, necessitating the .040 overbore. The crank is still round but 0.0015 worn. Were it not for the burnt piston, I'd probably have re ringed it and gone on down the road.

If you choose to do an in-frame rebuild, be absolutely sure to do a very good cleanup after using a hone or a glaze breaker on the cylinder walls. (Yes, that's necessary). I remember one engine I did a re-ring job on before making a cross country trip from California to Tennessee. It was a flathead six in a 1960 Rambler American. By the time we reached Nashville, I was having to stop and add oil between fill ups of gasoline. When we tore the engine down the oil ring expanders were rubbing the cylinder walls, and the compression rings were worn to less than half their original thickness- - - - -totally worn out in 2500 miles of highway driving! I THOUGHT I had done a good cleanup after honing- - - -WRONG! Use a strong solution of dishwashing liquid and HOT water to scrub the cylinder walls with a stiff bristle brush, followed by multiple rinses with very hot water. Wrap rags around the crankshaft journals to protect them from the wash job. I learned that lesson the hard way!
Jerry

Just don't use any scotch brite power pads or such. A non coarse wire brush ok, you don't want to damage the metal in anyway.

Damage cast iron? Surely you jest! The stuff is tough as woodpecker lips! I use a round toilet bowl brush and a strong solution of Dawn dishwashing liquid, and scrub vigorously for several minutes. When you think the cylinder walls are "clean enough"- - - -do it again!
Jerry

I have some janitor friends at work that give me worn floor scrubbing pads, I cut cylinder diameter circles out of them, stack a few on some threaded rod and spin scrub the cylinder walls with a good soap. The pads are just heavy duty scrubbers, no abrasives. Cylinders come out white towel clean.

The conversation is entertaining but the train has jumped it's tracks. Going back to the beginning.

Oldtruckspapa's truck is getting a head job. Pretend you are a mechanic in a shop and you have other jobs waiting. The boss is frowning because you have been too busy flapping your gums. What needs to be done, to get the truck engine ready, before the head comes back from the machine shop?

William of Ockham. “The simplest solution is almost always the best.”

JoeH Our dirt floor got packed down so you could sweep it.