I have a concern about my motor.
Recently I did a mild make over on motor, it started out as a 95 454 "magnum".
I replaced the cam, lifters, pushrods and rockers with crane equipment.
The stock mercruiser oil filter adapter was replaced with a Rex billet adapter and all stainless lines, the stock oil cooler was replaced with a larger unit.
The distributor was replaced also.
The bottom end was left stock.
The heads, intake and carb were also replaced, but I dont think thats relative to this problem.
Heres the problem.
Prior to the change, the engine would produce approx. 30-35 PSI oil pressure at idle, and approx. 55-60 PSI above idle. Seems normal.
After the parts change, I ran a pre-oiler and the pressure was at 60 PSI. (the drill ran approx. 1100 RPM.) but I noticed that there was very little oil coming out of the pushrods, and after about 5 minutes, there was still no oil to the front few rockers.
I installed the motor and ran it up to break in the cam, all went well, motor runs good, but has 60 PSI oil pressure all the time.
I removed the valve covers to recheck lifter preload, and noticed very little oil was in the head. Concerned, I again ran the pre-oiler, and, again it produced 60 PSI but with very little volume to the top end, and it seems to take forever to get there.
I replaced the gauge and the sender, no change.
The pressure is being read from the point at the rear of the block to the left of the distrbutor.
I installed a mechanical test gauge, and it read 57 psi with the pre-oiler running about 1100 RPM.
I wil note that after the pre-oiler is run, it is absolutely covered in oil.
It seems as though there is a restriction preventing oil through to the lifter bores.
I remember back on early 396 blocks, when replacing the cam, it had to have a oiling groove either the rear cam bearing or the journal of the cam.
I checked tho original cam, it does not have a groove, nor did the Crane unit I replaced it with.
This is my first experience with the Mark 5 block, and as I understand it, it does not require any special mods when replacing cams.
Any ideas??
P.S. I noticed that this block is reffered to as a "priority main" oiling system. I cannot find any oiling diagram explaining this.
Help.