Rusted interal parts

Anyone with experience with rebuilding an older 6 cylinder 250 (GM lol) engine. The unit had been torn down to rebuild but due to unfortunate circumstances never reassembled. It was stored in an old school bus for a few years and the crank is somewhat rusted. Underneath the rust the journals seem in decent shape. Would a polishing make the shaft useable again or is a regrind mandatory? I used a scouring pad and it brings back some shine but there is still evidence of rust pits. The cylinder walls also have rust. Taper us about .006. Pass with a new set of rings or rebore required??

The price for the gaskets, shells, rings tossed in makes this attractive at $300. Worth a try? How much can a person expect to see out of this thing?

Reply to
labatyd
Loading thread data ...

Well it depends on what you want to do. I would grind the crank, bore it to the first oversize you can find. Then go from there. Not sure what Clifford Research still has on hand but they made some NASTY straight six parts.

formatting link

Reply to
Steve W.

Really hard to say without seeing it. Could go either way, a few (FEW!) minor pits on a bearing surface are not the end of the world, nor are a few on a cylinder wall, all assuming they are minor. A lot of huge pits are a very differnt story, however.

Reply to
PeterD

That's what my machine shop advised. Gets expensive. Not expecting to put a lot of miles on this unit and was just wondering what I might get away with.

Reply to
labatyd

I'm a little worried this is a bit too much. They look a bit too deep for my liking. It's cheap enough so perhaps it may go a few years. Just wondering if anyone has tried something like this before.

>
Reply to
labatyd

If you can polish off the crankshaft journals with crocus cloth to where it looks pretty decent, I think you have a fair chance that this will hold.

A short run down the cylinder walls with a fine hone will also tell you how bad it really it.

I had a similar experience some time back when I brought engine and pieces home from the machine shop, and it flash rusted in my van overnight. This was clearly not serious, but I wasnt very happy about it.

Reply to
HLS

This rust is much deeper. This option for a replacement motor will probably be discarded as of today. Today I've received the offer of two engines removed from vehicles and still assembled. Neither have run for a few years but the chances are far better with these. One is stored inside and the other still on a partial frame covered with plastic. The one stored inside is felt to be in better condition or the pesron wouldn't have bothered with it. I'm hoping. And the price is almost free. Part of an estate cleanup. I have to follow up on these. :)

It would be interesting to see just how far the rusty parts would go though. If I could get it for next to nothing I'd sure be tempted as a challenge. Those old vehicles are not too hard to work on and the time spent wouldn't be that great.

>
Reply to
labatyd

Very slight pitting and damage to a cylinder wall? Yes, I have. Took a while for the rings to (re)seat, but within about 500 miles it was only using a quart of oil every 1,500 miles or so. Considering the age of the engine, the quality of the oil (this was a long time ago), etc, that was not so bad.

Personally, I'd say there is no yes/no answer. More a 'are you willing to take the risk that it will not be satisfactory' answer. You may be happy with the results, and again it may not be what you are looking for.

I've done some horrible things to engines in the past, and recovered from them. (for example, one Olds engine so hot the plug wires litterally burned off the plugs, replaced the head gaskets and that engine ran flawlessly for several years until I sold it...) Then gain, I've seen things that one might think were relatively insignificant cause no end ot problems! YMMV!

Reply to
PeterD

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.