Noticed after an oil change that I had major leak coming from the filter area. Cleaned it off thinking I was just messy when I changed it but it came right back after a 20 minute drive. Got to looking and thought it was the seal above the filter so I changed it. That wasn’t it. It doesn’t leak when it’s off or idling, but as soon as I hit the throttle it starts pouring out. Looks like it’s either the pressure relief valve or the oil sender unit. Anyone ever experienced this issue. When I say a major leak I mean I drove 20 minutes one way then 20 minutes back and I was a quart low. Could it have anything to do with changing oil? I switched from 15w40 to 20w50 and the leak occurred the next time it was driven.

 

A possibility the rubber o ring of the old filter stuck to the block and is interfering with the seal of the new filter. Or possibly, new oil filter missing the o ring altogether.

 

I was hoping for that but when me and a buddy got under it we could see oil coming from above the filter

 

If this only happened after an oil change, I would change the filter for another. It's the only mechanical part that changed. Only other component was the oil. Maybe oil being a different viscosity is leaking easier. Maybe oil had excessive detergents that opened up an old leak?

 

Could be the oil pressure switch has failed 99-01 units will actually leak out of a tiny weep hole on the sensor once the internal seal fails. It could also be the oil cooler line connections or the 7/8 plugs in the same two holes.

 

I thought it may be the filter too so checked it, not it. Did find the leak though, not sure how to fix it. It’s circlec in red.

 

X1 .............. it does sound quite a rare occurrence. I would fit another new filter and ensure the old ring seal is removed and the new filter has a new seal fitted. There is no need to drain the oil out but you may need to top up the oil.

Oil Filter - Genuine - Paddock Spares

 

May be OP by-pass valve o-ring. Bottom of linked page gives a size. Engine manuals for D1 or RR P-38s from Rave have illustrations and R&R info.
https://discoweb.org/showthread.php?t=91491
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