I got my old 3.9 going yesterday. It's been sitting for over a year, and started OK after the petrol had got through from the tank. The only trouble is that the oil warning light is staying on. I don't want to rev it too much with the hope of it going out, as I could damage the engine. Could the pump need priming after all this time doing nothing, like they need after a re-build? Can I pour oil down the oil cooler pipe to save me taking the pump cover off and packing with Vaseline? Any help would be appreciated.
BOOMER
Bloke from Dorset
Could be your oil pressure switch up the creek or a loose wire giving a false signal and your red light.
I expect your hydraulic tappets rattled like hell after the engine not being run for a year, did the noise slowly die down?
If not, you've probably got hardly any oil pressure.
In which case getting the vaseline out to reprime the pump and checking the relief valve isnt stuck seems like a good idea.
I have heard that a sharp clout with a hard rubber or copper mallet to the side of the oil pump housing can sometimes work in getting the valve to unstick.
Dont use a normal hammer in case you crack the cast alloy housing!!!
Hope this helps.
I expect your hydraulic tappets rattled like hell after the engine not being run for a year, did the noise slowly die down?
If not, you've probably got hardly any oil pressure.
In which case getting the vaseline out to reprime the pump and checking the relief valve isnt stuck seems like a good idea.
I have heard that a sharp clout with a hard rubber or copper mallet to the side of the oil pump housing can sometimes work in getting the valve to unstick.
Dont use a normal hammer in case you crack the cast alloy housing!!!
Hope this helps.
Irishrover
Well-Known Member
Definately prime the pump.You could check the relief valve whilst you are at it, but I think it unlikely that it has stuck open due to the spring pressure on the cup/ball. I had a 3.9 Vogue and left it for two months and it just wouldn't start because the lifters were empty and the valves not opening enough. Flattened the battery 3 times before the oil got round and she fired up. Rattled like a steam train until they filled.
Check the lead to the oil pressure switch has not come adrift and touching off the engine.
I used to love the look on the assistants face in Boots when asking for a LARGE tub of Vaseline!!!!!!!
Check the lead to the oil pressure switch has not come adrift and touching off the engine.
I used to love the look on the assistants face in Boots when asking for a LARGE tub of Vaseline!!!!!!!
classic kev
Well-Known Member
Oil Pressure Light!!!!
Tell me about it. The light came on as I stopped at a set of lights after having done some lanes. The motor was running and no apparent problems but oil light on says stop engine ASAP. Anyway, I took my oil pump off today and found the relief valve was stuck.
On an engine that hasn't been run in a year it could be a combination of pump needing primed, stuck relief valve and/or a dicky pressure switch.
Would say first off, prime pump. Try the notched threaded rod on the end of a drill down the dizzy hole method first - its a lot quicker. You might also want to consider draining the sump and changing the oil.
Unfortunately I don't know of an easy way to remove the pressure relief valve without taking the pump to bits, you can remove the spring but the piston is unlikely to come out and without taking the pump off, you are unlikely to know if the valve was stuck.
I agree that if you have low or no pressure top end would rattle, lots. All I can say is be careful and good luck.
Tell me about it. The light came on as I stopped at a set of lights after having done some lanes. The motor was running and no apparent problems but oil light on says stop engine ASAP. Anyway, I took my oil pump off today and found the relief valve was stuck.
On an engine that hasn't been run in a year it could be a combination of pump needing primed, stuck relief valve and/or a dicky pressure switch.
Would say first off, prime pump. Try the notched threaded rod on the end of a drill down the dizzy hole method first - its a lot quicker. You might also want to consider draining the sump and changing the oil.
Unfortunately I don't know of an easy way to remove the pressure relief valve without taking the pump to bits, you can remove the spring but the piston is unlikely to come out and without taking the pump off, you are unlikely to know if the valve was stuck.
I agree that if you have low or no pressure top end would rattle, lots. All I can say is be careful and good luck.
