Wrong Engine Bearings?
Despite my searching on this site, the internet, and talking to professionals I was unable to find an answer. This usually means I have missed something major and I really don't know what I am doing.
Currently I am rehabbing my G63B 2nd Gen 1988 Ram 50. I purchased the EK106AM master rebuild kit from a company selling DNJ products. My problem at the moment is that the Main Bearings (MB105) Plastigage (Green) at 0.0032in to 0.0035in at (with two different torque wrenches) 37Ft-lbs-39Ft-lbs. From what specs I can find it should be between 0.0008in to 0.0020in. So this is way out of spec. I measured the bearing thickness and found them to be (with Harbor Frieght calipers) approximately +/-0.0800in. According to King Engine Bearings its a similar thickness (0.0784in) they sell for the Main Bearings for this engine. I have also measured the crank journals and found them to be on spec. 2.2435-2.2441”.
I have talked to two machinists about the issue. The first machinist said it's probably the wrong bearings and get King Bearings. However King Engine Bearings states they sell the same size bearings. The other Machinist said “just run'em. You you must have the right bearings and you are just missing something.” I have also talked to a automotive tech who has worked on these engines and owns one himself. He said get undersized bearings. All I can find in undersized was .25mm, .50mm, and .75mm. I am not sure what the sizes for the bearings are referring to. If .25mm is for the thickness, then the bearings might be way to tight.
What am I missing?
Throwing caution to the wind I have installed the crank. Wrong main bearings or not I will find out if they will work. One theory is that the extra oil pressure from the deletion of the balance shafts will help offset the slop in the crank. Not to mention a little thicker oil.
Hopefully the piston rod bearings come in at spec. If the rod bearings don't, I guess I will just go with that too!