Hello, new here and looking for some input. I recently rebuilt my F134 for my 67 CJ-5. After startup i noticed I was not getting oil up to the filter. Today I removed the pump and made sure it was functioning as should. I cleaned the pick up during rebuild. Its frustrating. I have been talking with other motor guys but they like their V8 and could care less. Any help would be appreciated
oil pressure issues
- Thread starter Mike79
- Start date
F4 oil pumps cn be a pain to get going. I had to resort to packing mine with vaseline & cranking it over with the plugs out to get things flowing.
jeepdaddy2000
Well-Known Member
Two questions:
First, did you have an oil pressure gauge on the engine and what was it reading.
Second, if no pressure, what was your total run time before deciding on shutting it down.
I ask because you can run briefly on the assembly lube, but after that run the risk of damaging the bearings and cam.
First, did you have an oil pressure gauge on the engine and what was it reading.
Second, if no pressure, what was your total run time before deciding on shutting it down.
I ask because you can run briefly on the assembly lube, but after that run the risk of damaging the bearings and cam.
53A1
Member
I'm wondering the same thing. You should be going by what your pressure gauge is reading and I'm assuming it's zero? I always use a good mechanical gauge for this. I'm pretty sure the oil filter is passive with the oil system so you can have oil pressure and no oil in the filter. Not sure what would cause this though and it's not normal.
I had a tough time getting oil pressure when I rebuilt mine. I packed the oil filter and used a hand pump and injected oil into the oil galley. I think it took at least 5-10 seconds to get pressure. Been a long time.
Like jeepdaddy is said, this is no time to mess around with no oil pressure. Pull your plugs so there is less resistance and double check everything and prime as much as you can. Engine first starts are stressful that's why builders lather parts in assembly lube and oil when assembling. I'd run additional zink if it has a new cam and lifters.
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thanks all, i believe the oil gauge is a 6volt and i converted over to 12 so that is still something i need to address. I would assume i should be getting a stream of oil from the line to the filter housing which i do not have. im not sure about the packing with vasoline i have not heard about that or have the slightest clue. I have it drained and plan on double checking the pick up and using a hand pump to try and pressurize the passageways just to make sure there isn't a blockage.
chemironsdad
New Member
Welcome to the group. Don't let the V8 guys discourage you; the F-head is a great engine, but it does have its quirks, especially when it comes to the oiling system.
53A1
Member
The pump consists of two gears. When you add the vasoline you increase the vacuumn created by closing all the gaps between that would reduce any leakage and cause it to take longer to build pressure. You would normally be able to prime the system with a drill but the distributor drive gear is on the distributor and there's no way to use a drill to prime on the F134.
There's a top cover on the pump. You remove that and pack the gears with grease. Make sure your paper gasket is in good condition and surfaces are clean and flat. Don't use any sealant especially RTV. Can't remember if there are shims to adjust gear clearance but there might be. Usually there is a procedure to check wear by using feeler gauges. I'd do that also.
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Packing the pump works because of the material difference between gases and liquids.
With the the pump full of air (a gas), the gears can spin and alternately compress and expand the air without forcing the air out of the pump.
Liquids are not compressible.
The vaseline acts like a very viscous liquid.
Stiff enough to stay put but soft enough to be pumped.
The moving gears force the incompressible liquid to squirt out of the pump and pull oil in to replace.
The vaseline is petroleum, and dissolves quickly into the engine oil.
With the the pump full of air (a gas), the gears can spin and alternately compress and expand the air without forcing the air out of the pump.
Liquids are not compressible.
The vaseline acts like a very viscous liquid.
Stiff enough to stay put but soft enough to be pumped.
The moving gears force the incompressible liquid to squirt out of the pump and pull oil in to replace.
The vaseline is petroleum, and dissolves quickly into the engine oil.