oil pressure

ivysboy · Post by **ivysboy** » Mon Feb 20, 2017 4:12 pm

Hi 3.5 ltr. removed sump removed oil pickup and thoroughly cleaned refitted new gasket and refitted the sump. put in new engine oil 20/50 new oil filter and run engine . the pressure went to 30 lb .( this has a mechanical oil gauge) drops to 20 lb after a few mins then down to 5 lb even when revved. switch off for 5 mins and the pressure does the same ie 30. 20 . 5 lb tried changing the pump gears with good used ones but still the same. what should it be when hot?

anybody have any ideas. would be much appreciated. thank you . Ken.

Blown v8 · Post by **Blown v8** » Mon Feb 20, 2017 4:39 pm

Did you use a new gasket on the oil pick up pipe ?
Could be sucking air there !

ivysboy · Post by **ivysboy** » Mon Feb 20, 2017 5:19 pm

Blown v8 wrote:Did you use a new gasket on the oil pick up pipe ?
Could be sucking air there !

hi yes new gasket fitted

ivysboy · Post by **ivysboy** » Mon Feb 20, 2017 5:21 pm

Hi yes a new gasket was fitted

harvey · Post by **harvey** » Mon Feb 20, 2017 6:46 pm

P5B/P6B 3.5 litre should be 30-40psi @ 2400rpm HOT. Later engines will differ from that because of the improved oil pump.

gelmonkey · Post by **gelmonkey** » Tue Feb 21, 2017 7:25 pm

What was the pressure before please?
I have seen home modified pick up pipes that have curved on the base that meets the block gallery and oil was being picked up and then dumped at the top of the pipe before it even got to the pump.
The curving was caused by welding /brazing the pipe to the mounting plate.
Not saying you have this but if pressure was good beforehand then its something fairly simple I reckon.

P

Ian Anderson · Post by **Ian Anderson** » Tue Feb 21, 2017 7:58 pm

My guess would be a faulty gauge?

Have you tried bleeding any air from the sender area? Crack the sender to release any air from behind it when the engine is idling

Ian

ivysboy · Post by **ivysboy** » Thu Feb 23, 2017 9:12 am

gelmonkey wrote:What was the pressure before please?
I have seen home modified pick up pipes that have curved on the base that meets the block gallery and oil was being picked up and then dumped at the top of the pipe before it even got to the pump.
The curving was caused by welding /brazing the pipe to the mounting plate.
Not saying you have this but if pressure was good beforehand then its something fairly simple I reckon.

P[/qDon't know as purchased this with head gaskets leaking water into the sump . engine been stripped down and heads done and all new gaskets fitteduote]

ivysboy · Post by **ivysboy** » Thu Feb 23, 2017 9:16 am

Ian Anderson wrote:My guess would be a faulty gauge?

Have you tried bleeding any air from the sender area? Crack the sender to release any air from behind it when the engine is idling

Ian thanks for that. do mechanical oil gauges go wrong?] will do as you suggest and try bleeding out any air. thanks. Ken.

ivysboy · Post by **ivysboy** » Thu Feb 23, 2017 2:24 pm

ivysboy wrote:
Ian Anderson wrote:My guess would be a faulty gauge?

Have you tried bleeding any air from the sender area? Crack the sender to release any air from behind it when the engine is idling

Ian thanks for that. do mechanical oil gauges go wrong?] will do as you suggest and try bleeding out any air. thanks. Ken.[/quote

Thanks Ian. slackened the oil pipe from the gauge until oil came through tightened it up and now got good oil pressure. thank you very much. Ken.

Ian Anderson · Post by **Ian Anderson** » Thu Feb 23, 2017 6:19 pm

Thanks for getting back Ken

It was just a hunch but glad it worked

Ian