Well in one of my past posts I thought I had a bad oil pump even though it is brand new. I now know that is not the case. I spent hours today jacking the engine up , dropping the pan and putting a another new oil pump in the engine. My engine is a 89 350 which has been stroked to 383. I understand many of you feel priming is a waste of time. I have alot of money in this thing and I am afraid of hurting the engine. I started it twice both times for about 10 seconds and got no reading on my dash gauge. OK maybe I should have run it longer but the story goes on. I went to the auto store and got a gauge which is direct fit to the block with a oil tube on it. Then I took out the sending unit and put the oil line and gauge in its place. My engine builder tells me if I use a priming tool and a drill there should be some kind of pressure there. OK I tried it twice and nothing. Even with the hole in the block open I get no oil at that point in the block. The oil filter fills up with oil and there is a slight drag on the drill. How does the oil in these engines flow? I took off the filter and bypass and everything looks OK there. I see there is another plug right above the oil filter looks to be 1/8" pipe. Whats that for? How come I don't get any oil at the sending hole?? HELP

 

you need the distributor or an actual priming tool. I think anyway the oil galley needs the distributor to guide the oil the right directions. put the distributor in the block and keep the power off for the moment. crank it over untill you see pressure on your mechanical guage plugged back in on the back china wall.

 

The little plug by the filter is just another spot to put a mechanical gauge. If assembly lube was used then priming the motor is a waist. All you are doing is washing off the assembly lube, but if it wassent used then priming is a must.

 

Is the Welch plug in the main oil gallery installed to the proper depth?



Normal oil flow:

 

umm...just because you use assembly lube doesnt mean that you dont need to prime a motor. there are 2 main reasons for priming, one big one is so you can test for oil pressure and flow by taking off the valve covers and watching the oil come out of the rockers. the other reason is because unless your gods gift to engines (your not...so dont think it), your assembly lube could have easily rubbed off from installation, or if you incorrectly lubed it, and its a high compression engine, you need to be priming.

anyways...one of my co-workers had his pushrod V8 re-machined. he gets the block home, measures it, and assembles it without incident. he skipped on the priming and decided to start it. well it was good for the first day, but the second day there was a knock. he blew a few rod bearings and had to strip it all the way down again. the cause was because when he got the block cleaned and machined, they removed the bypass plug and never installed it. all the **** from his motor just went straight into his pump and back to the bearings. coulda been avoided by watching the gage when priming and taking a look at the filter.

the way i see it, if you spend more than 1000 buks on something, you had dam well better do your homework and practice good due-dilligance so you dont embarrass yourself.

EDIT: did you take off a valve cover and check for oil at the rockers? thats a pretty important part of confirming oil movement, just because theres pressure, doesnt mean its going everywhere.

 

Hey thanks for the flow chart. I agree I want to be safe. I do not have any oil up top at this time. I was thinking the engine builder changed the oil filter fitting to a nonby pass kind.He says alot of guys do that and it makes all the oil go through the filter. Is that so ?? I have also been yold by others you don't always get oil at the rockers when priming?? Is that so?

 

OK another update. I took your advise and plugged off the hole above the oil filter and moved the gauge up on top by the distrbutor and have 60lbs of pressure. Now what? How is the factory gauge ever going to work??

 

Full-flow filters are actually hard to find. If you use plain, off-the-shelf oil filters, there's a good chance there is a bypass spring holding the element in the filter canister. Filters usually go to bypass at a little under 10 PSIG differential pressure.

There may not always be oil apparent at every rocker arm if the engine is not rotated while there is oil pressure. Unless there is about 800# of pressure, it's not going to compress the valve spring and get past the disc/piddle valve in the lifter.