Oil pressure test pilot needed

[jesfirth]

Hi all,

I have a fully rebuilt 4.2 engine complete with a new set of oil, water and power steering pumps just dropped back into my car and it has been run up for a few seconds. It has plenty of oil but no oil pressure.

I dont want to run the engine up with no oil pressure whilst we try things in case of damaging it.

I would prefer to turn the engine over on the battery with the coil leads disconnected to avoid damaging the engine, but as I have no oil pressure I dont know whether any oil pressure will register if I do this.-(chicken and egg)

Please, please could someone take their coil lead off and turn the engine over on the battery and see if the oil pressure comes up at all.

If it doesn't I will rethink my appraoch

Thanks

Jes

[longbow]

You need to prime the engine with a drill or hand pump, you can get a drill pump from machinemart for around £15. Attach one end to the feed to the oil cooler, break off the feed to the block and prime until oil is seen to be flowing from the feed pipe. Then attach this pipe back to the block. Then you should back-prime the engine oil pump by attaching the drill pump feed pipe to the lower block oil feed and forcing oil into the pump - the resistance will be much higher so watch the drill as it will be working hard. I did this after my rebuild and had positive oil pressure on the gauge before I then turned the engine over on the starter. BTW if you just want to turn the engine over on the starter, pull the fuel pump, injectors and ignition fuses in the boot. If you need more guidance, drop me an email. As you are aware, turning over a new engine on relatively dry bearings can be very damaging!

This is the pump I bought/use: www.machinemart.co.uk/shop/product/details/cpp3000-drill-powered-water-pump/path/miscellaneous-pumps/brand/clarke

Edited by longbow on Wednesday 2nd May 11:43

[jonnyw]

Jes, Longbow is right, the oil guage is a wet system so what you see is what you get, all the best John

[byker28i]

Did you fill the oil pump up with oil on reassembly? It's probably got air in it and needs to prime.

[jesfirth]

thanks chaps for the help much appreciated

all sorted now

The pressure relief spring did not seem to be working properly-despite it being brand new!

With the addition of a thin (circa 0.5mm) thick washer on the spring the pressure at idle is 40. So a new spring is needed by the sounds of it.

Jes