A guy needing to come up with some money in a hurry to keep from getting evicted from his house has put several '60s and '70s era Chevy pickups up for sale for real cheap. I bought a good running '77 today for the SBC 350 and auto tranny (cost me $50). I'm also looking at a '70 3/4 ton for it's drive train (also priced at $50), but the seller said it had thrown a rod when he was driving it a couple of years ago. I looked carefully at the engine and oil pan and can't see any piston or rod damage externally. I was wondering if maybe when the guy was driving it the oil pump dropped down from where its supposed to be mounted and bound up the crankshaft. Has anybody ever had that happpen or seen what kind of damage to the motor that is likely to cause? I'm wondering if maybe the 350 SBC's lower end can survive that type of oil pump failure. Your thoughts? Oh, and this isn't really OT because the engines and trannies will go in early Ford rods.
I haven't got any good ideas. However, the bottom line is that the pan has to be dropped and the damage surveyed. Anything else is pure guessing. The damage could be just about anything, broken rod, ventilated piston, lose timing gear, broken oil pump, bad distributor, broken crank, lose flywheel, see.
Never Heard of such a thing (oil pump falling off ) but sounds like a 4 bolt main motor....i'd buy it.
For $50 its probably worth the risk. Worst case is that if it is oil pump related, it will be the pickup falling off. Could have wiped the bearings but you'd still have a set of heads, intake, carb, dist, tins, etc. to put on a new shortblock. Worth the $50. Plus there's selling the rest of the truck. A mid '70s pickup without motor/trans is got to be worth a couple of hundred with no hassle. I know a guy right now looking for a bed.
Yeah, the ram's horn exhaust manifolds are worth something too, and I'm thinking that I could put the cab of my 39 Chevy COE on the '70 3/4 ton chassis as well. I'm sure I'll get my money's worth if I buy the '70 GMC pickup, but was just hoping that the 350 engine may not be toast. Maybe I'll see if the seller will let me drop the pan before I buy it.
If by a remote chance the single bolt holding the oil pump to the rear main came off, the oil pump would drop and the distributor would quit turning causing the engine to stop running. Like everyone else, I have never heard of this ever happening. Stranger things have happen though,
No oil is better than water temp .failure As long as it didn't bind or break anything It is rebuildable ,For 50 Id go for it..Still could double your money ,
No, it's more than just a rod knock. The seller said the motor is bound up. He has other pickups for sale for $100 that have either a slight rod knock or a lifter tapping noticably.
To clarify, I am particularly interested in the '70 GMC 3/4 ton because it would make a good platform for my '39 Chevy COE project. The 350 engine is a secondary concern, but still a concern.
ok ,,,,the fact that the guy was driving the vehicle at the time says that the dist. was still driving the oil pump,,it would not have developed a knock if it actually threw a rod,, that is usually a term people use when they hear a knock ,,,buy it,, worst thang would be damage at the base of the cylinder,, no problem,, I too am guessing that the bottom skirt of a piston broke and then you will hear a knock,a double knock resembling a main problem,,,buy it,, turn the crank,, put 305 chevy rods in it and go
From what I have seen usually the rod bearings lose a tang and both bearing shells end up over on one side of the rod, seizing up the engine. If so the crank will need turned but sometimes it warps the crank and they aren't worth fixing. The machine shop that I have used for years just tells me to go buy a crank, they are so cheap they can't grind one for the same amount anymore.
At 13.00 per hundred pounds you can not go wrong buying a 400 pound engine for fifty bucks, you're still ahead 2 dollars. If you can buy a 70 3/4 ton for 50 bucks you are ahead 350 dollars.
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