In the process of converting an '87 TBI truck engine from hydraulic flat tappets to hydraulic rollers. New heads, cam, lifters, pushrods and rockers.

Installed everything, no manifold, no valve covers. Fill 'er up with oil and spin the oil pump clockwise with a drill at 2500 rpm (simulating an engine speed of 5000 rpm). 50+ psi on the dash gauge. See oil at a few of the rockers on the drivers side and oil flowing out around some of the driver's side lifters that are at "high" positions in the lifter bores. Crank the engine slowly with a wrench on the snout and the oil around the lifter bores jumps from lifter to lifter on the driver's side only. I end up getting oil coming up through the pushrods to all the rockers on the driver's side, though it does take some time.

Passenger side, all the rockers are bone dry. I don't see any oil coming up any of the lifter bores on the passenger side even after rotating the engine slowly through 720 degrees while running the pump with a drill.

Any ideas? What should I check? What can I try?

Any help much appreciated.

 

You're using the wrong priming tool.

 

Whew! I think you're right. I'm using a Mr. Gasket 3795 primer. It's pretty narrow and does allow oil to come up the distributor hole. Sounds like I should be using one more like a Proform 66896 that has a bushing similar to the distributor. Pictures of both attached.

Thanks for the quick reply. I was getting a bit worried. Never thought it could be the primer...

 

The best oil priming tools are old distributors with the gear ground/cut off.