Technical Cleaning a machined block

I have previously rebuilt Ford 226 flathead six cylinder engine I'm going to replace the current 226 in my truck. The current engine needs machine work while the replacement engine checked out good, good round cylinder bores and the crankshaft is in very good condition. The engine came out of a parts truck about ten years ago. I don't know much about it other than it had a remanufacturer label on the side.

The question I have is about cleaning the engine. It dirty inside. It's been suggested to me to have the block hot tanked to clean it up before installing new rings and bearings. Will hot tanking it harm the machined surface of the cylinders? Most times an engine is hot tanked it's before having machine work done.

Second, I have a pressure washer with I used to clean the outside of the engine before I disassembled it. I was thinking of just pressure washing the inside, and out again, blowing off with air and then coating the entire block inside and out with WD-40 to prevent any flash rust. I was told hot tanking was the way to go.

 

Remove all plugs you can, use bottle brushes in every passage. I’ve bought a brush kit for engines. Rifle bore brushes work great for small oil passages. You can soak them with WD or a penetrating fluid before you start. I’ve also just honed cylinders with very minor tapering and re-ringed. If your using the original pistons makes sure the ring lands are clean and free from carbon. Lisle has a tool for it.
The older hot tanks used a caustic chemical that hurt cam bearings and most cylinders were bored after that style of cleaning. It’s suprising how clean you can get a block with degreasers and brushing and not hurt cam bearings if they are good.

 

I second what jimmy six said but I’d like to add that the term hot tank gets thrown around a lot. You need to ask the shop what type of cleaning equipment they use. Even after the initial cleaning and machine work it needs an assembly wash. Most shops have jetwashing equipment that use mild detergent that clean like a big dish washer and won’t harm anything. That’s what I used for years. If you go with the pressure washer route which I’ve done try to use hot water. It cleans better and evaporates off quickly and helps from rusting before you get your WD-40 on the machined surfaces.

 

First engine I rebuilt for someone else's use was in a gas station run by my fellow racer, Bob Taylor, who built all his race engines himself. When we got the engine back from the machine shop, I was all ready to jump on it, but Bob had me wash the newly hot-tanked block down inside and out with warm, soapy water, including the oil passages. I think I washed that block three times before it passed Bob's inspection. I used paint brushes, toothbrushes for the tight places and bore cleaning brushes for the passages. I've passed that on to my own kids and their friends and while some might call it overkill, the engine was in use every day as a utility vehicle for the local grocery store. We took care of the regular maintenance on that engine for the three years before I left California, and it never gave a minute's worry. A little preventive care before assembling an engine is something that is absolutely necessary as far as I'm concerned. As far as using WD-40, you'd be better off using Gibbs or Boeshield T-9. I use T-9 on all my cast iron machined work surfaces.

 

Amen!! I took one of my 8BA's to a local shop for cleaning, honing and cam bearings, when I got it back the hole for the oil pump was still packed with caked on oil and dirt. I took it back and he redid the Hot Tank, still had to dig and scrape the area for the pump. Got ready to assemble it and something told me to dig a little deeper and make sure everything was clean. Ran a wire into the oil passages and came up with crap on the wire. Took it outside and put the Pressure Washer to every hole, nook and cranny several times. It's amazing how much crud can hide in an old block. Alot of people just don't care nowadays, "give me your money and get out"! Ya want something done right, do it yourself.

 

Don’t forget the rest of the parts , an amazing amount of crap can also be found in cranks, rods and piston pins

 

Hot tanks mostly don't exist any more....but jet washers do, as well as ovens.

For an engine that doesn't have much caked on crap, you can clean it out with solvent, then Dawn or similar soap and water. Like they said, remove plugs, use long brushes to clean out the internal passages.

Have fun, if you do it right, you'll get dirty/wet

 

I've read that Kieth Black would use only Tide to clean out his blocks

 

I'm with the pressure washing and scrubbing crowd. I like the foaming spray engine cleaner. It seems to me that it kinda hangs around a bit more and soaks junk loose better than the regular, really thin spray stuff. Hot water would be preferred if you have access to it for both pressure washing and also following up with soap and brushes. If it doesn't need any machining I would not have it cleaned in a "hot tank" that uses the caustic material.

Lynn

 

Does anyone have a hot tank with caustic in it any more? with all the aluminum heads on everything, seems it wouldn't get much use. I have not had anything cleaned in one since the 1980s.

 

I fed a number of hot tanks in two machine shops I worked at in the mid 70's and when I saw those new fangled washers I new the world had gone pussy.
Pre assembly block cleaning steps after hot tanking.
1.Wash with hot water and Tide.
2.Repeat.
3.Repeat.
4.They can't be too clean!
5.Don't argue with your boss about it either, ask me how I know.

 

I’ve only witnessed Jetwash,,and bake clean these days,,,,,,someone might still use a caustic solution these days,,,,,but I don’t know where .
Jetwash does a very good job,,,,,,but it won’t be perfectly clean (,,nooks and crannies) ,,,,and some spots of paint will remain
Baking and shot blast,,,,it will look like brand new iron,,,,,perfect !

From the op post,,,,it sounds like a good home cleaning will do,,,,,,gunk it down,,,,hose it off with hot water if available.
Then wash it with dawn,,,and use the the water again.
Then use the rifle cleaning brush set to clean all the passages.
Then clean it one last time,,,,,and blow dry if possible,,,,if not ,,,wipe it down quickly and lube with a good protective oil,,,,,(WD40 my go to ).
A pressure washer will work great since you have one ,,,,,,really very well .
If you are not boring the engine,,,,(just rings and bearings ),,,,,,I would hone it good before final wash ,, but,,,( I’m assuming you knew that already I guess) .

Tommy

 

Dawn dish soap is my go to now and when I use my pressure washer I connect to the hot water tank in my garage. Before building a new racing GMC they would go to strip clean both head and block; but that’s all gone now.

 

I haven’t seen a “ hot tank “ in a shop in years parts washers that function similar to a dishwasher are common as are ultrasonic washers for aluminum parts.

 

Degreasing tanks using hot lye have been replaced by citric acid solutions.. If the block will need machine work many shops have the 500F degree ovens and steel shot blasting

 

Since the early '60s when I started assembling SBC race engines I always used hot water and Tide in an old spray gun. As others have stated I always removed all the plugs from front to back and brushed out all passages. An old engine builder friend told me that after everything is spotless wipe down each cylinder with a white towel and atf, you'd be surprised how much grit will be removed from each cylinder. The atf will help cleanup the crosshatch from honing.

 

me too, I still do that...

 

I thought the white towel with ATF was mandatory for removing grit?

 

Don't wipe down with the old style red shop rags, especially new ones, they lint off.
Remember an instructor (claimed) he took apart an automatic transmission that had been recently rebuilt and found the filter plugged, it had been wiped down internally with red shop rags.

 

I don't know what my machine shop uses. I know they have an old hot tank as it is an old establishment. I've had them do my 312 and my 401. The blocks came back spotless inside and out. The first engine I had them do was my Y block. When I picked it up I asked if I should scrub it with soap and water. The answer was, no it is clean. I didn't believe this so I took an ATF rag and ran it across the bores and machined surfaces. I didn't find any dirt or grit of any kind. The inside of the water jackets were grey cast iron. Bottom line, my machine shop, Bearing Service Portland, OR, does a very, very good cleaning job.

 

My machinist tanked my GMC block twice, don't know what in, but there was still rusty crud falling out of the water jackets. I took my newly machined block to a company that chemically strips car bodies and the block came back looking like a new casting. Next time I'll go there first. A bath of oxalic acid works on rust, but you need to degrease the block first.

 

Hand washing works great! A power washer is even better! Make sure to chase all the threads. AutoZone and O'Reilly's have thread chaser kits in their rental programs for free.
https://www.oreillyauto.com/detail/...k-1994-ford-f-150?q=thread+restorer+set&pos=8



As stated, get an engine brush kit and clean out all the oil passages........



A broken compression ring works well for cleaning out ring lands and is cost effective.



Follow up with a 5 gallon bucket filled with Dawn dishwashing liquid, brushes and wash mitts. Scrub, scrub, scrub then rinse well and rinse again. Bathe everything in WD-40 and you're golden!

 

Worked there in the mid 70's, they did a lot of roundy round work,Winston West, etc.

 

Taps aren’t thread chasers! You are right. Your last 2 photos will get me thrown in jail today. I’m a lot more sneaky doing it to day.

 

I have to kind of laugh that this stuff is so interesting to me. LOL
But I enjoy all the technical talk.
Even the mundane stuff.
But it's important!
A lot of times, I just listen and take mental note.
Other times, I interrupt...
Carry on.

 

The first thing is to remove all the press in and screw in plugs.
The second thing is to pressure wash the block including all internal passages.
The third thing is to run wire brushes thru all passages until they are clean.
The fourth thing is to pressure wash the passages one more time.
THEN take it to the machine shop for cleaning.

Its my understanding that if you have a block bead blasted, that you need to also get the block decked and align honed.

When you get the block home, wash with detergent and rinse well and give it a blow dry with an air gun.

 

Agree with the wash it 3 plus times comments, but I use Palmolive! It leaves your hands feeling soft and smooth, your wife/girlfriend will appreciate it...

Seriously, a good grease cutting dish soap and the pressure washer routine followed by blow drying. Just don't use your compressor unless you have a dryer system, it will have too much moisture. Don't laugh, but grab your leaf blower. It moves enough air to get the block dry enough when followed by a wipe down with a rust preventing oil on the machined surfaces.

Regarding rags and lint, many years ago I learned how to deal with precision gears and bearings. Paper towels work okay, but if you can get them, those cheap ass folded paper towels that don't seem to ever dry your hands tend to be the most lint free. And kerosene is what I learned to use for a final clean up just before assembly. Keep wiping until the towel comes out clean.

 

You Guys are friggin Crazy!! 100% Correct!! Still friggin Crazy!! Excellent thread!!! Thanks!!! Pete

 

No.

 

i remember an old time engine builder talking about how to install the heads an engine he was always afraid of some grit hidden in the head falling into the engine when tipping the head over to install it so he would fill all the water jacket holes with shaving cream it would not let any hidden grit or dirt fall out and would dissolve on filling with water