Engine has been sitting for 2-3 years. Started it today for a short test. Got no oil pressure. Afraid to run it very long. Could the oil have run down and it just takes awhile to come up. Can not run for very long ....no coolant yet. Phil
I had the same problem with a '51 Merc that had been sitting for 20 years. I pulled the pump and everything looked good. I didn't want to take any chances, so I replaced it with a known good pump that I had, which I had packed with Vaseline. That one gave me oil pressure in less than 10 seconds. I subsequently sent the Merc pump to a guy on the "Ford Barn" who could test it. He said it tested out to 47 or 57 psi (I don't remember which as I had sent him two pumps to check). I think your pump has "lost prime" and enough oil has drained out of it over the years so that it can't prime itself. I would drop the pan and repack the pump (regular grease works, but the Vaseline dissolves easier afterwards, I guess). I would also do a cursory check of the pump when I had it out. The only number I can remember is that the end clearance on the gears should be less than .006" Don't quote me on that; it's pretty easy to get the correct number from the manual.
I agree with Tubman. Worth the time to pack the oil pump in case it's lost it's prime. (Assuming you've cranked it a bunch already without letting it run). OT, but I just got a brand new engine from GM that sat since 2014. No oil pressure no matter how long we cranked it. Had to pump oil in to get pump to prime. Sent from my iPhone using H.A.M.B.
You can make a tool to prime the pump, I'm assuming if you pull distributor there's the pump shaft. Tool matches distributor shaft (like a big flat blade screwdriver), chuck it in a drill. Mine I put a short piece of thin pipe over end to hold in place. Like the last post I would consider replacing the pump and still manually prime it. I wouldn't want to run an engine even a few seconds without oil pressure. Sent from my SM-S320VL using Tapatalk
oil pump on the 8BA runs off a gear in back of block cant prime like that sevenhills. pull the oil pressure sender out pump oil in hole with a squeeze bottle should prime pump.
Thanks, I didn't know. How is it driven and can you run it with a drill? Sent from my SM-S320VL using Tapatalk
Sorry...I just read paleot's explanation. One car I had years ago the oil pump was on front of crankshaft, no way to prime it. Thanks for explanation. Sent from my SM-S320VL using Tapatalk
Just removed the sender, grounded case, key on, and checked it with an air hose........gauge needle didn't move... I'll check wiring and or replace sender/gauge.
You have to pump quite a bit of oil in thru the pressure gauge hole, enough to fill up the oil galleys and the pump cavity. I've even used this method on a SBC way back when. I left a customer's half worn out '56 draining while I changed the filter and greased all the front end fittings and it lost prime.
Found it! Bad battery wire going to the oil gauge (Omega). Had pressure, just didn't register on the gauge. Thanks for all the suggestions. Phil
Low pressure problem came back. Saturday I had 15lbs at a idle, Sunday I had nothing. I finally got the engine apart. At this time I have not seen anything wrong unless the pump just won't put out the pressure. The bypass spring looked ok and the bypass seat looks good. I have not disassembled the pump yet but the shaft feels a little loose vertically. It's not very far by oil galley to where the pressure gauge mounts. I have not checked the pickup tube for blockage yet. Tomorrow......
Today. No blockages between the pickup and where the pressure gauge screws in. Gotta have pressure there if the pump is pumping. Pump drive? I can reach the gear through the pump hole and it seems solid. ??????? I gonna get a new pump anyway. Can there be a plug missing somewhere that I am not aware of in an 8BA?
The crankshaft has tiny freeze plug-like plugs that when removed provide access to the oil passageway providing oil to the bearings. When an engine sits, the passage of oil in the crank can become plugged leading to reduced or no oil pressure. I have learned to pop these plugs out, clean out the oil cavities, and then of course replace the plugs. It's been a while, so I can't recall how many of these plugs (3 ?) need to be removed & replaced. Something to consider when troubleshooting oil pressure issues.
Post your question on Fordbarn. Also do a search. Here's a start. https://www.fordbarn.com/forum/showthread.php?t=196120&highlight=oil+gallery+plug
Are you using an electrical or manual gauge? The original post says you found a electrical problem. If electrical then try a manual to verify the electrical isn't working.
I don't like electric gauges either, just don't trust them. So if I'm having an oil pressure problem the first thing I do is check it with a mechanical gauge of known accuracy.
PROBLEM FOUND....Whoever assembled the engine left the plug out of the front of the oil galley. Had to remove the timing cover and gear to discover it. Thank you Lord..Hallelujah... Phil
YEs, don't use grease! Yech! Vaseline will dissolve into the oil as soon as it gets up to temperature, grease may not (probably won't, depending on the grease). Grease is designed to be tough, to be resistant to dissipation, and many brands have long chain polymers added to give the grease tack and adhesion. Grease is likely to plug things up in the system, don't use it!
Just kept diggin' till I fount it. When I worked for (General) Lee Edwards Racing he fired a guy for leaving an oil galley plug out. Engine blew up on the dyno... Phil
Glad you found the issue and got it corrected. I didn't see where you had a mechanical gauge hooked up is why I mentioned it thinking either the electrical gauge or sending unit was at fault.
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