An odd question!! I have the opportunity to purchase a 351W roller motor with 12K miles on it. It was originally in an E250. The owner had a bit of a problem with a fuel line and the engine bay went up in flames melting the upper intake to some degree (must have been quite hot). The block appears to be fine. But, I'm thinking the level of heat during the fire and the "rapid" cool down when dowsed with water likely left potential cracks and weak spots in the block? For those engine experts out there what do you think?
It's entirely possible for there to be cracks in the block and or heads if the fire was hot enough to melt the aluminum intake. Unless this engine is free, I would personally keep looking. 351w's are too plentiful to risk getting a hunk of scrap.
In an engine fire the aluminum parts can burn before the block gets hot enough to have any damage to it. Just make sure you get in writing that you want to have the block and heads checked to be rebuildable before you pay for them and you will be fine. I doubt you are going to find any problems with the heads or block that aren't covered under normal rebuild work. Aluminum melts at just over 550F and cast iron melts at about 4 times that temp. You can see that the iron is probably fine - but protecting your purchase is always a good idea.
Melting point of aluminum is higher than 550*F. Lead melts at about that point. Aluminum melts (depending on the alloy) at about twice that temp. Put an aluminum pot in your oven and set it to "clean", I'll bet the pot won't melt. I would pass on that block just due to it being dosed with cold water while it's on fire.
Yep! working from memory is never a good thing: It should have been Celsius not Farenheit. Aluminum melts at 1215F (650C) and Iron melts at 2300F (1260C) alloys have different temps and the silicon and nickle in cast raises the temp by about 500F (300C). So the cast iron block has a melting point of about 2800F the aluminum melts at 1215F - still over twice the temp. I would check the block - there is no need to pass on a good block just out of fear. It makes sense to have the facts before making a decision on a purchase.
Thanks for all of the input. I would be purchasing it from an individual so there really is no way to guarantee the block even if it is in writing. I think I'll pass. I just wanted to determine if others were thinking as I was, hot block and cold water not a good idea!
my uncle used to buy burnt engines from the salvage yards all the time, the salvage yard owners were scared to death of a burnt engine, so they were cheap. Here's some things to look for, if the vehicle burnt in a wreck, and the bottom radiator hose didn't burn off, it didn't get hot enough to hurt the block. The top end is where the heat will do damage, it well get really hot under the valve covers, the seals will bake, and the springs can loose their pressure. Also if a carb or other alum intake parts melt it will find its way into the cylinders, he always pulled the heads, touched up the valves, added new springs and seals, pulled the pan and cleaned it out, added new seals, dropped in something else and drove it. If a vehicle burnt while sitting in a building, the engine is junk.
I built a 302 about 20 years ago that came out of a car-b-que. We tossed the heads in favor of 351W's [the hot item at the time], had the block boiled and worked, used the same pistons,rods, and crank. Never had any problems with it, might have just been good luck.
Only seen them at a junk yard nothing left to burn so would it be melted together? I have seen cars at auctions that are burns go for 100 bucks is nothing salvageable on those complete burns doors etc. Or is it scrap metal
when a vehicle burnes in a building, 99% of the time the building burns down too, it gets super hot, and stays that way, it gets hot enough that the pistons melt in the block, alum trannys melt, so yeah, its scrap.
