My neighbor just got finished installing a new cam and cam bearings in his 88 truck with the 300 six. Earlier in the year he replaced the crank, main and rod bearings, and oil pump after which he had good oil pressure.

After the cam and cam bearing replacement, when the truck warms up, the oil pressure drops to zero and the lifters start to tick. This only happens when the oil gets hot.

My guess is that either his oil pump is going out for some reason, his pickup tube has fallen off or is damaged in some way.

Am I in the ballpark or is there some other reason he is experiencing this oil pressure loss? He plans on replacing the oil pump today unless we can figure something else out. Thanks for any info.

Wayne

 

From what you told us; I believe the cam bearings are over-reamed or the tolerance from cam bearing to cam bearing journal is too wide. He did finish ream the cam bearings after installiation?

This would be indicated by low oil pressure. I have never heard of a cam wearing out in a 300?

 

As gearman said it will be the cam bearings causing the issue there. IMHO.

They must also be aligned correctly when installed and one or more may be out of kilter which would cause what you describe.


tom

 

I just found out that he did not replace the cam, just the cam bearings. The old cam bearings were so bad that the front and rear bearings just fell out when he removed the cam.

Actually the cam bearings were not the cause. He had good oil pressure with the old cam bearings and the new ones were a tight fit. This would not cause "0" oil pressure when the truck was warm. He replaced the oil pump and so far the problem has not come back. Thanks for the input.

Wayne

 

Glad to hear it is working like it should. Go figure cam bearings worn out the cam should be too Imho but ya know ford they always got the ability to get something better than right.

tom