[LLLosingit]

I picked up a GM iron 6.0 that was burnt pretty good, Hot enough to melt the aluminum valve covers but aluminum heads and water pump/ front and rear covers/oil pan are still whole. The only thing I want to reuse are the block/crank and maybe rods and pistons. I already have the heads off and other than some surface rust (no pitting) the cylinders look ok. I just wonder if the heat would distort the block to the point that it's not feasible to use it again.

 

[MN Hemi]

A thermal cleaner brings the block to 550°. Use that as your reference point.

 

[LLLosingit]

A thermal cleaner brings the block to 550°. Use that as your reference point.

That doesn't really help that much when I have no idea what temp the block reached when the truck burned, I figured someone has tried to rebuild a burnt engine at one time or another or maybe a machinist might see the post and have some first hand experience.

 

[fla1976]

Send to a machine shop for a check. They can check for cracks and warping.

 

[cardo0]

Myself I would avoid and pass over any block from a car fire and more so in the engine compartment. Also a motor from a front-end/head-on accident.

 

[Topfun99]

Honestly, unless that engine was sitting in a fire for an extended amount of time (15-30+ minutes) AND that fire was on the ground below the engine, I wouldn't worry about the block. Heat rises and the mass of the engine would make it difficult to heat it up much past a couple of hundred degrees, certainly less than 400-500deg F.

If it was a typical engine/car fire, the air feeding the fire would come from the sides and underneath. This would somewhat "cool" the engine.

Take the engine apart. Bearing babbitt typically melts at 400-500 degrees. I'll bet you won't find any melted bearings.

 

[fast38ca]

Well just for a reference my neighbor got a escalade that was burnt bad. Sounds like same as yours, valve covers melted. He has been using the complete short block for probably 5 years now. It was obviously taken apart and inspected but it is working for him.

 

[LLLosingit]

Take the engine apart. Bearing babbitt typically melts at 400-500 degrees. I'll bet you won't find any melted bearings.

Got it down to the shortblock tonight pulled a couple rod bearings and they look like new. I'm going to drop it off at the machine shop and get it cleaned and checked. I only paid $40 for it so I'm not risking much.
Thanks for the replies.

 

[BIGBALDGUY]

Did the firemen spray cold water on the hot block? Mag and/or pressure test it. JMO

 

[engineguy]

Short block from a burned vehicle will be OK. You might even consider it to be a "seasoned" block.

 

[RegalRocket]

My snowmobile had an engine fire bad enough to melt the track off and through the tunnel.

The engine had air box damage, but the throttle cables, carb boots and plastic balance tube was fine.

Heat rises.

 

[cardo0]

Sorry to bust your bubble but aluminum conducts heat very well. And heat cycles not only change an aluminum objects dimensions but the heat treat it was cast/fabricated with.

It's taken for granted when weld repairing aluminum heads the heat treat is destroyed and the head is no way as strong as it was manufactured. I guess I'm being to nerdy here as the block more likely will have a long life on a street motor. But my point is it's just added risk buying and using a motor from a fire. Myself I would look for something else at the same price or more cause even though the block is only 40 bucks you risk the money in the parts you put in .

Well good luck and I'm not condemning that block by any means. Just giving you my 2 cents because you asked for it.

Merry Xmas!

 

[cindys_sn95]

Short block from a burned vehicle will be OK. You might even consider it to be a "seasoned" block.

this! have used/built several 5.3s from burned chevy trucks and never had any problems.