Re: oil pump conversion

Posted by Jack Vines On 2019/7/11 11:36:40

When a "rebuilt" but with unknown details has a problem, it can be difficult to diagnose.

In this case, I recommended beginning with the lowest viscosity petroleum base oil and a known accurate aftermarket oil pressure gauge. This gives a baseline.

While not likely, sometimes over-use of sealants can block that drainback hole in the rear main cap and cause a leak.

Overfilling can cause a leak at the rear of the pan gasket indistinguishable from a rear main seal leak.

If all else fails there is the conversion to a neoprene rear main seal.

A bit off topic, but I was asked to diagnose why on a recently rebuilt engine, the rocker arms weren't getting any oil. I knew what the problem was as soon as the shop owner started waffling on how he'd cleaned the rocker arms and shafts. Finally, he admitted he'd just washed them externally with solvent. The rocker shafts are always clogged internally with crud. Proper rebuild requires complete disassembly, removing the end soft plugs, rodding the inside of the shaft with a bore brush, regrinding the rocker tips and reassembly. Then, the rocker arms oiled as they should.

I only mention this as we have to consider the engine as a system and what else might be causing the OPs problems.

jack vines