O-ring oil pump, Picture needed Options

[Chad911sc]

So on my new 2056 I have been getting low oil pressure numbers after the oil gets hot. I have 85 lbs at start up, but after it gets to 220, I’m only getting 5lbs at idle and 45lbs at rev to around 5grand. I do have an external filter/fan combo that could be contributing to my issue. After it gets past 190 the valve opens up and lets the hot oil into the external fan cooler combo. I changed out the 26mm oil pump to the 30mm offered on LN engineering, but still same problem. The reason I ask about O-ringing my pump is because when I changed out the pump to the bigger one, I noticed that my case was gouged in 2 places where the pump press fits into the case. I’m thinking that this could be my culprit. That the oil is just pushing back into the sump from those digs in the case halves. I also ordered the piece from Tangerine racing to replace my oil valve spring inside the case, as I still am using the stock spring as of now. I’m going to pull the pump back out of the case this weekend and I will post a couple pics of the gouges in the case.
I was wanting to know exactly where this o-ring would go on the pump, so I can take it to my machine shop and have a grove beveled into it. One more thing out of the equation to solve this problem.

[Chad911sc]

That’s what I had in my engine when I built it, the CB maxi-pump 26mm. Changed it out due to low pressure. Obviously that wasn’t the problem because the 30mm is not providing the pressure when hot either. Hopefully the Tangerine valve will fix it. I always wonder if the oil level is correct on my dip stick. It shows full, but if the oil is draining back into the sump after it is turned off, my oil level is actually low due to the hoses and cooler itself.

[Superhawk996]

Obviously that wasn’t the problem because the 30mm is not providing the pressure when hot either.

That’s some faulty logic there - if you have a leak between the pump and case - a bigger pump doesn’t mean more pressure at the oil pressure sensor - it just means more volume bypassing and/or escaping back to the sump due to the clearance between the case and the oil pump which doesn’t change between a 26mm and a 30mm T1 pump - both will be undersize OD.

You’re on a good path to replace the relief valve with the Tangerine setup.

If that doesn’t do it - you’re right back to dealing with the shitty T1 pump situation.