The 4 1/2" stroker for my Hemi is covered in rust. The journals are nice and shiney still, but the counterweights are surface rusty. What's the recomended method of getting it clean again? Is wire brushing the way to go? Will a wire brush hurt the journals if I accidently hit them? Also the rear main seal area is slightly rusty. How much will that affect it's sealing ability? Thanks. -Bugman Jeff
Rust on a Crank?? If I ever find rust on my crank, I'm gonna have to give it a spanking! Here's one method of removal to try. electrolysis
You can get the rust off with Naval Jelly, and it won't hurt any part of the crank.It also works as lube on your other crank.--TV
Dip it overnight in Evaporust -- it removes rust without taking any metal with it -- doesn't stink, and when it's used up you can flush it safely. www.orison.com is where you can find it. later, Steve.
The active ingredient in Naval Jelly is Phosforic(sp) acid.The same stuff sold as Metal Prep,or Ospho, for wiping down car bodies.Another solution is Mollasses and water.
[ QUOTE ] The active ingredient in Naval Jelly is Phosforic(sp) acid.The same stuff sold as Metal Prep,or Ospho, for wiping down car bodies.Another solution is Mollasses and water. [/ QUOTE ] It's also in most Cola drinks. Diet won't attract ants....
Since acids attack the base metal (even phosphoric to some degree) I would be very careful to be sure none gets on the journals. The last thing you want is to get them etched! Molasses would be safe, especially if you coat the journals with grease (even better, attach old bearings with hose clamps) since molasses will not attack any oil based products. If the surface rust it very minimal then soaking a few days in diesel fuel would do it. Use a Scotch Brite pad to help it along. I used this method on a long stored Merc flathead crank I scared up. In every case protect those journals.
Stick it in a big plastic tub of hot water with 5 lbs or more of sodium bicarbonate, hook up the biggest battery charge you have, you need around 200 amps and up. negative side to your crank, positive to a decent sized piece of non magnetic stainless, and turn on the power for about twenty seconds. Switch off and reverse the conections, Zap it again for about five seconds. Pull it out and rinse off with tap water. Coat it with clean oil immediately you've dried it. Rust can re-appear in minutes in the right environment. Make sure there is no oil on the crank at all before it goes in. Oily areas won't clean.
Polisher, I've never heard of this method before..... How much rust will it remove? I come across old bike parts that this would be perfect for. Thanks,
can a machine shop clean off a thin layer of rust on the journals? i oiled down the journals before bagging it, last weekend i looked and there was some RUST
200 amps huh? Would a welder work, 'cause I got a whole lab full of them. I would assume that a welder would have to many volts, and be to dangerous.
Also, does it have to be stainless? My supply is a little low. How big a chunk do you suppose it'd take for a whole crank? Thanks.
As odd as polisher's advice sounds, I'd follow it. He has had a lot of other good advice. I've used his polishing supplies, and I highly recommend them. His advice also makes metallurgical sense. --Matt
As weird as it sounds guys, if you use some WD40 or PBlaster and Kraft paper, alog with a little elbow grease, it'll take the rust off pretty easily, with no risk of any damage.
I'd recommend Evapo-Rust too. Just wash it off with parts cleaner or something and leave it in a tub of Evapo-Rust and it'll be COMPLETELY clean in no time.
GREAT STUFF GUYS!! i'd like to see this in the Tech-o-matic section. someone email Ryan and ask him to move it there.
did anybody suggest a soak in marvel mystery oil? or there is always the "good ole boy okie fix"... a soak in diesel... either of these will soften the rust up to the point that a Kleenex (tm) will probably get it off.
Hell, take a grinder to it! Actually, I would bring it to a machine shop and just have them polish it (NOT grind it). It wouldnt cost a lot of $$.
Bugman, 1. Cover the rod and main journals with duck-tape to prevent them from ANY damage or scrathes. If they get nicked or scrathed, that changes the RAA finish of the journal and will ultimately cause bearing damage. 2. Take a 3M scotch-brite and "Elow-Grease" and remove the surface rust from the crank. 3. Then coat the crank with a mixture of 'WD40 & transmission fluid. 4. If your not going to use it for sometime, bag it and use a vacuum cleaner to suck the air out of the bag and seal it up. Best Regards, Glenn Hayes Champion Spark Plugs Fel Pro Gaskets Speed Pro Performance Parts
If your gonna zap it with electolysis, use washing soda, not baking soda. Washing soda is available in the detergent section and looks like a big box of Arm And Hammer, but its not. Also, you can use rebar for the sacrificial piece but the sheet of stainless will have more surface area . It is best to surround the crank with the anode for line of site , like a bar at the 4 corners. IIRC stainless will produce a gas, not sure though. the crank gets the negative side in traditional electolysis.
Considering the original question was asked sixteen years ago, I'm hoping he got the rust cleaned off before now...
That makes three of us! I have a 265 crank from my 57 Chevrolet 265 block, that the guy delivered to me (block and crank for $80.00-delivered). Crank had been sitting out of the block for years; it was't scale rust, just surface rust. So, I cleaned the oil off, dipped it in Evaporust, washed it off, dipped it again, washed it off again, and oiled it down. Crank looks good, and may not even need to be turned. I'll know more in the spring when I start on this engine, and take the rotating assembly into my machinist, for pressing pistons on the rods, and balancing. He'll do what's truly needed. One of a very few people that I trust completely. I am Butch/56sedandelivery.+
"Considering the original question was asked sixteen years ago, I'm hoping he got the rust cleaned off before now... " Yeah, but it's rusted up again since then.
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