I had a 340 short block rebuilt in 2018. I pulled the engine this winter because the rear main seal and the timing cover seal leaked and a bad lifter knocked occasionally, for a few minutes after startup. I thought I might as well get the cam lobes checked since I already had the 340 torn apart. I noticed that the cam bearings looked scorched… kind of bluish or dark on the bottom. There was only 2,500 miles on this rebuild.
I checked all the main bearings which showed about the same wear and dark areas. You can see in one picture that a small area of copper shows through. I checked a few rod bearings and they looked fine. I plan on replacing the cam and main bearings.
This summer the engine overheated. The gauge did not bury and probably maxed out at 2/3 of its travel, by the time I shut it down. Some antifreeze and steam came out of the radiator overflow for a few minutes.
When I originally installed this engine I primed it with a drill and I think it had about 60 lbs of pressure on the gauge, that I temporarily installed. But the 69 Swinger only has an idiot light, which I believed worked properly. So, I don’t know what the actual oil pressure was during daily drives.
I temporarily reinstalled the oil pump and oil pan and replenished the oil. I primed the oil pump and a small flow of oil did come out of the holes in the bottom of the bearings. I reinstalled the cam and rotated the cam and the crank in small increments, but no oil came out of the pedestal in each head and it showed no oil pressure on the gauge . But there was a massive stream of oil pouring out from the oil galley behind the No. 8 exhaust lifter bore. And there was no oil in the other bank’s lifter bores. I didn’t think at the time, to reinstall the lifters and see what effect that had. I expect that this is the normal oiling; where the oil goes from the oil pump to the oil galley on the passenger side and is distributed to the rest of the block, if the lifters are in place. Can this be confirmed?
Does anybody have any words of wisdom on the extreme bearing wear? Thanks!
I checked all the main bearings which showed about the same wear and dark areas. You can see in one picture that a small area of copper shows through. I checked a few rod bearings and they looked fine. I plan on replacing the cam and main bearings.
This summer the engine overheated. The gauge did not bury and probably maxed out at 2/3 of its travel, by the time I shut it down. Some antifreeze and steam came out of the radiator overflow for a few minutes.
When I originally installed this engine I primed it with a drill and I think it had about 60 lbs of pressure on the gauge, that I temporarily installed. But the 69 Swinger only has an idiot light, which I believed worked properly. So, I don’t know what the actual oil pressure was during daily drives.
I temporarily reinstalled the oil pump and oil pan and replenished the oil. I primed the oil pump and a small flow of oil did come out of the holes in the bottom of the bearings. I reinstalled the cam and rotated the cam and the crank in small increments, but no oil came out of the pedestal in each head and it showed no oil pressure on the gauge . But there was a massive stream of oil pouring out from the oil galley behind the No. 8 exhaust lifter bore. And there was no oil in the other bank’s lifter bores. I didn’t think at the time, to reinstall the lifters and see what effect that had. I expect that this is the normal oiling; where the oil goes from the oil pump to the oil galley on the passenger side and is distributed to the rest of the block, if the lifters are in place. Can this be confirmed?
Does anybody have any words of wisdom on the extreme bearing wear? Thanks!
