Hey guys, thanks for the replies
Bugga mate thats not good.
Was the pump new? Or at least tolerances checked?
Was the block dipped (bathed) before the rebuild?
All oil galleries cleaned out & blown out as well as the pick up?
The pick up adaptor threads sealed?
The oil in the gauge line isn't being sucked out, its the air in the line expanding again after the pressure from the engine drops & pushes the oil back into the engine.
99.99% of gauge installs don't get the air bled out (as it can make a mess in the car) but over time the line may end up full of oil instead of air.
the pump is a new JP pump
i didnt have anywhere locally to get the block dipped, but i did blow out the oil galleries before re assembling.
im sure i put sealant on the pickup but thats the only thing im not totally sure of now
You would have had to swap out the sump and pick up pipe on the 202 for the LC sump & pick up on your 161. When you installed the oil pick up from the 161 to the 202 did you ensure the flare nut was properly tightened and the pick up was in good condition?
i did indeed swap the pickup and sump from the 161 onto the 202. before i put the sump on im sure i tightened the flare nut, and if asked a few days ago i would have said i was 100% sure. but now im having trouble in starting to think maybe i didnt. the pickup was in good condition and was fine in the 161.
Sounds like a leak on the pickup side as above. If it makes oil pressure from the start then the pump probably isn’t the issue.
i had a very similar intermittent low/no pressure problem years ago on a 308.
Ok when cold but when fully warm pressure would disappear after a big squirt. Why? The oil level in the sump was then low enough to uncover the crack where the head of the pickup joined the pipe.
The crack was very hard to see.
Thanks for your experience, i bet that was frustrating trying to find a hairline crack.
ive got one more plan of attack to try in the next day or so, depending when i get into the shed next.
i think i may have put too much Vaseline in the pump possibly, so will try and clean a heap of it out, and ive got a threaded fitting to put into the block and force some oil into that to give it enough to hopefully get something happening. only other guess will be pulling the oil pump off the 161 and trying that because i know that works.
im just worried ive wasted the bearings now, just hoping the small amount from the filter each time ive tried has been enough to keep some kind of protection.
if that dosnt work engine will be out and sump off checking the pickup.
Thanks for your help guys will keep you posted, i really do appreciate it.