So is there one way to clean a block that will get rid of oil, grease, crud, paint and rust ??

I take mine to a local engine builder. He bakes the block for me. Comes out looking like a fresh casting, spotless. I think he charged me $60.

Some here appear to bead blast them as I have seen the oil passages come back full of small media bits.


No matter who cleans it and how always use solvent and brushes to clean all the oil passages. Not trusting anyone to do that good enough. Same with the crank oil holes. Clean parts until your sick of it and then do it again.

I believe that's the most common way nowadays, caustic chemical hot tanks have been prohibited in many areas but still remain in some.

This outfit is close to me,only way I'll ever have anything stripped/cleaned again.Anything that comes out of this place looks as new,cast iron,sheet metal,aluminum etc.A complete car body looks like an assembly line product.You can let it sit for 6 mo and no rust ,when ready to paint all you do is wash it down with soap and water and you're good to go.These are not hot tanks,everything room temp but don't know if something of that nature is available or permitted in your area but I would find out if possible.

http://www.mecchemicals.com

The shot blasting systems use stainless shot that is non magnetic--it comes out easy as pie--This is a wonderful way to clean rust and years of junk

The shot does however work on the edges or the lifter bores and so a Ball Broach lubed and used in each lifter bore is a must--NO honing--that just makes grit that is very hard to remove--Goodson makes lifter ball broach kits and any shop worth it's salt uses it on older blocks to help promote smooth lifter operation no matter if block shot blasted or not--More often old "worn mushroomed lifters are yanked out the top of lifter bore thus scoring lifter bores--Dumb! They should always go out the bottom to prevent this
Hope this helps
I LOVE bake and shot blast ( no sand or glass media ever If I can help it)

You mention paint too. Are talking inside or outside? Inside, I know the guy with bndautomotive that makes quantum blue lubricants has a formula he came up with using distilled white vinegar. I've read posts of his. Might just be for flushing though, I don't recall for sure. I don't know if it's worth your asking just throwing it out there. http://bndautomotive.com/

Oustide, brake clean?

Shot blasting ensures the need for fresh machine work.

I can't see "baking" removing rust !! We're talking surface rust on the outer bare areas and rust and gunk in the water jackets - that being my main concern.

I always clean the block up a reasonable amount before handing it over. This is just removing the freeze plugs and using a coat hanger to dig any clods out of the water jackets ect., and a decent degreasing.

When the block comes back I brush everything with solvent multiple times and clean out the oil passages. What I have seen on a relatives engine a few years ago was the oil residue in the oil passages collected the media pellets and then they stayed put until you go after them with a brush. Some machine shops will tell you it's clean because they blew air thru all the passages. but that method simply doesn't cut it.

For the outside of the block if it's rusty just wire brush it's clean. No big deal.

If you have something with super neglected water jackets one might be able fill them with Evaporust or sim. before taking the block to the shop to ensure it comes out as clean as it can be.

To clean up inside the block and the lifter galley area a new toilet brush and some solvent in a spray bottle is great.

The shop calls it baked but it could be hot tanked. All I know it is free of oils, paint and rust when I pick it up.

Mechanical rust removal generally is preceded by “baking” to rid of grease and paint.

Most shops around here call it “bake and blast”.

After baking at 800 degrees the block is placed in a Wheelabrator which is simply a rotating cage holding the part that has a fan wheel that spins and throws shot at the part.
After that it goes in to the jet wash.

You would be surprised to see how much shot makes its way in to the cooling passage and gets rid of rust, of course you want to remove all the core plugs before the blast op.

You of course need to perform all the machine work after this process.
One more trip to the jet wash.

Once home get out your rifle cleaning rods that range from .22 to shotgun.
I always hone the lifter bores before the block goes to the shop.

Then wash with liquid clothes detergent, rinse then oil it and bag it ready for assembly.

The last one I did MANY MOONS AGO was hot tanked the bead blasting in select areas THEN whirly birded ....

This is what my shop does. Comes out really nice. Been using it for years and it does take care of rust BETTER than a hot tank.

Don’t forget the inside of the block. Water passages clear of rust deposits helps keep the motor cool. Before taking the block for cleaning plug the freeze plug holes and pour in some muric acid. Let sit for about 30 minutes and then flush with water, the water dilutes the acid. If you have a gravel driveway that’s the best place to do it. After you are finished flood the area to totally dilute the acid. Make sure there are no pets around and be careful with that stuff. Very toxic fumes.

Here we go again. Everybody wants to try the latest trick. I have a Better Engineering block washing cabinet. (That doesn't work because it only cleans the outside.) I have a drum of Evap-o-rust. (That doesn't work because it won't remove paint or grease.) I have and ultrasonic tank. (I doubt that it would work and I sure don't want to put a greasy block in there.) Blasting doesn't work because it won't get the rust out of the water jackets or the sludge out of the oil galleys. Baking might do something but I want my block clean everywhere. Muratic acid will work in the water jackets if you leave the core plugs in and block everything off but I would sure rinse with something other than water to neutralize. (Possibly baking soda.) The only thing that works for real is a 50 year old caustic hot tank. Not every shop can do this now-a-days, but find a shop that can. It is the only one step process that will get your block perfectly clean.

Ive had some of the worst of the worst sludge filled and what look like 2 oil changes on 100k miles and I always pre clean a bit and my local shop does what looks to be a fine job.

I only have them tank and clean and then they do use some sort of media and all looks good.

But even after getting it home and doing all the brushes, cleaning, washing with hot water with compressed air right there, even leaving the block out in the summer sun to help it dry how much time do you really spend on cleaning prior to assembly?

Ive never got a block back from any shop that I considered clean.

Even the dipstick tub isnt immune.

AND how many small block guys pound out the rear hidden plug, many shops dont and thats one ugly passage.

Here is one that one of the last things I do is run assembly oil through all the passages, oil itself has good cleaning properties. As mentioned a gun cleaning kit, pipe cleaners ect.

Its not hard to get all the cleaning residue out if your the one doing it, you know what you used and what comes out and compressed air with a long thin tip is your friend. I use a length of ss nitrous tube with different attachments on the end for a long reach.

This is my next to last step, using new engine oil, you can see it runs out clear but if you run the cloths through you see what you left. My last step is a rag over every outlet and I blast them with starting fluid because it leaves zero residue.

Well, I’ve done numerous blocks using muric acid and have always used water. I guess baking soda would work but I never found that to be necessary. Every cook has his own recipe.

The problem for me is the unknown. You hear about people using some acids and after the rinse the acid keeps eating. Since I don't know enough about it I would want to neutralize. Muratic acid works so good it's unbelievable.

You use muriatic acid to help control your pool's PH, so water does have an effect.