A Mopar friend of mine started to work on his V6 4x4 Dakota pickup. It needed a clutch and the idle oil pressure was zero. This V6 is 3/4 of a 318 V8 with 150,000 miles on it. His plan was to drop the oil pan and change out the oil pump. I convinced him to change out the rod bearings, main bearings, and rear main seal as long as he had it apart. Having done this to my '75GT 460, I explained all the details (as though I'd ever worked on a Mopar) and warned him to remove the belts from the front of the engine as they would hold up the front end of the crank and prohibit insertion of the front upper main bearing. (I learned this the hard way). He did all as I instructed but still could not get the upper front main bearing in beyond a quarter rotation. He felt that the timing chain was holding up the front of the crank. He finally solved the problem by loosening all the main bearing caps and hanging about 400 pounds on the front crank snout. Just wondered if any one else ever had this problem? The front upper main bearing rotated right in on my 460 once I loosened all the belts. Seems hard to believe a 150,000 mile timing chain could still be that tight. Friend also said he wasn't going to take my advice anymore!
Could it be the timing cover and front seal caused the front of the crank not go get enough clearance to change the bearings? I know I pull the timing cover on a cheby to do that. Never messed with a ford or dodge though.
I did a 400 Mopar with no issues,,, Went right in front to back,, I have a little bearing tool that goes into the oil hole and as you rotate the crank it pushes the bearing into position
I changed the lifters and push rods on a SBC on the side of the road once. I reused the intake gaskets and filled the radiator with water from a nearby pond. It was a work truck so it's all good.
and also a chevy...Haha just kidding, don't want to go down that road again. Also how are the bearing serfaces on the crank, becasue wouldn't it be useless to change them if the serfaces were toast? Dave
The crank journals looked just like new. The used main bearings looked good. The rod bearings were pretty washed out - probably the source for low oil pressure. The friend used a short wood dowel for a bearing tool, but still had the problem. As a last resort, we would have pulled the timing case cover and timing chain. Frankly, at 150,000 miles, I'd have changed out the timing chain and gears anyway, but friend didn't want to - tightwad!
