Electrolysis for the block and other rebuild questions??

Sat Sep 25, 2004 8:04 pm

Well, I got the stuck pistons out, at first it looked like this would be a quick rebuild, you know rings and gaskets, but on further inspection:

1) It looks like the crank will need a polishing or grinding, slight scoring visable, and can be felt with the fingernail. If I can gete away with a polishing does anybody sell bearings a little under standard size?

2) If the pistons or bores won't clean up and I have to overbore where can I get the high compression pistons I seen discussed here?

3) I plan to dunk the entire short block in my hot tank and then remove the cam and crank, or should I pull the cam and crank before hot tanking?

4) And the last question, after the hot tank I thought about building a little bigger version of the 5 gal. experiment I've got going now and using electrolysis to clean the serious rust problem I have in the block water jackets? Anybody done that, pro's/con's ??

:D Thanks, Glenn :D

PS, I'll take some more pictures of the whole mess tonight and post tomorrow.

Sat Sep 25, 2004 8:09 pm

Don't do it as the black goop as I call it will get in ALL THE OIL GALLEREYS
you will not be able to remve it all.
I will be just like adding a hand full of sand to the oil.
If the block is that bad you can try to replace or thae it to a good shop & have it boilded & also have them clean all the galeys.

Engine Repair

Sun Sep 26, 2004 12:38 am

You need to pull everyting apart before boiling the block.

I do not recommend putting the block or other internal engine parts in the electrolysis tank. Take the engine to a good machine shop and let them boil out the block. Have the machine shop check the crank - If the scoring is not to bad you may be able get by with polishing the journals. I have had one crank repaired - built back up then turned to original specs at about 1/2 the price of a new crank.

Now is the time to get estimates on repair costs. If you have to turn the crank, bore the block, purchase over sized piston, rings, mains and inserts, then valve work ---It may be cheaper to purchase a rebuilt engine.


Cleaning the block with electrolysis

Mon Sep 27, 2004 1:27 pm

I must be in the minority because I have used electrolysis many times to clean an obnoxious casting, including engine blocks. I like to strip everything out so that I can clean it and power wash it afterward. I also use a piece of cork, wood, or duct tape on the ends of iron wire or rods so that I can push them into the water jacket voids without the ends shorting against the casting sides.

Any oil galleries can be cleaned the a gun cleaning brush and a bit of soap. Then rinse, rinse, rinse. Even a hot tanked block needs to have the galleries cleaned. Otherwise, you are just left with greasy broken down oil resudue and some lye trapped in there. Afterall, hot tanking is just soaking it in heated lye water, where as electrolysis will actually kill the red rust and convert it to Fe3O4, or magnetite. Once converted this black oxide you can knock the loose stuff out, so after you scrub, brush, or power washer blast, it will be very clean after you rinse, rinse, rinse. I like to use hot water to rinse with as it gets the casting warm so it dries faster. It will so clean you'll have to quickly oil the bores so they don't flash rust.

I always clean the oil galleries out even after a trip to the machine shop so I don't have a chip finding its way into a new bearing. You can do a great deal of good with an air gun, but scrubbing with a gun brush really cleans them out. Eastwood even sells such brushes.

But, if you're really concerned, just hook a low pressure air hose up to an oil port and let it bubble while the cleaning takes place. That way nothing will get in there while it cooks.

Mon Sep 27, 2004 4:47 pm

Weren't all our engine blocks sand castings????? That said we ought to get one to clean up Galleries and all if we have a large enough tank to do electrolysis..

Availability of rod and main inserts.

Mon Sep 27, 2004 10:38 pm

Just thinking. Just because the tractor parts books only lists oversized inserts of .040 and .060 doesn't mean they are not available.

Check with several top notch industrial parts - machine shop suppliers. You will need the journal size and the inside size of of the mains and rods. I have the feeling that smaller undersized inserts could be found with a bit of research.

Sun Oct 03, 2004 7:18 am

you can get the bearings from your local napa store. the part # for a undersized bearing is 1455 cp 2. i don't remember if this is for the rods or the mains. hope this helps.