Oil Pumping problems

[edbaus]

Hi,

I have a question on my 3.6L motor problem. Here is the whole story.


This is in my race car. It is a stock motor except for upgraded cams. It is a 1990 motor that I just rebuilt (I am fairly experienced at rebuilding)

The oiling on my car runs from the motor, to a system 1 oil filter with an-16 ends on both sides (I have been using it for a year now with no issue), then to a pair of mocal filters (brand new) then to a front mounted tank. The breather at the top of the motor is vented to the front mounted tank.

OK, freash motor on the dyno. It made 258 rwhp. Spent at least 3-1/2 hours tuning the motor on the dyno. No issues at all. Checked the oil level in the tank while the motor was running and there was a half a tank as I am used to.

Went to the track this weekend. Friday it was cold and a little rainy. Got out for two sessions. The first session was a little wet, but the second was dry and I really was able to open it up. It ran great.

Saturday. Colder (low 50's) and still a little damp. Lined up to go out for the first session. The oil pressure fluctuated a little, so I checked the tank for level. There was no oil showing in the tank. I added 6 quarts to bring it to level. I went out and the car did not have power. The oil temp started to rise and before I could get back in, the distributor plug was ejected from the motor and oil sprayed all over. (still had good oil pressure all the way)

They brought me back in and I dumped the oil to find out where all of the oil from the tank went. All of the oil was in the case.

I took apart the oil filter it was crushed (oil enters the outside and exists to the opposite end from the inside). I removed the crushed cleanable element, so now there is nothing in the cylinder to slow the oil down. Put the right amount of oil in the car, started it up, and all the oil got sucked into the motor, then the oil started to get returned to the tank from the breather.

I have removed one, then the other, then both oil coolers from the circuit. By taking both off, the oil kind of returns but still spits out the breather.

I am thinking that maybe the oil filter getting crushed caused back pressure in the line that sheared the key in the oil pump so the gears are spinning on the shaft and not pumping the scavenge side of the oil back?

I am really open to ideas here. (before I drop and disassemble my motor)

Thanks

Ed