volvoshredder wrote:
Coburn, didn't you use a b21 oil pump on your engine?
Coburn Performance to the rescue. Despite all popular prattlings about me being tied up in the basement or lodged under a mountain of car parts, all untrue (or at least that's what I'm forced to say). I am, in fact, paying a certain amount of attention, but am spending most of my evenings working on my cars and my days are so busy that I haven't been able to check the board.
On with the answer. I did use parts of a B21 oil pump with the B20 bottom section on my engine. That's what I was able to scrounge from Greg's parts pile and my collection of pumps. They are physically the same, only the pick-up is different.
Now for the bad news, almost any B20 pump you get (or B21) will have a ball bearing check valve and the spring that controls the release pressure will be warn on one side due to it rubbing on the housing. It is a faulty design and the cause of most pump failure. Good luck finding the spring (Olof maybe? Valentine?).
You can get the high pressure spring from IPD, but that is only for the later B20 pumps with the plunger style valve (and if you find this style of pump, I've got the high pressure spring). Volvo then went back to the ball style valve with the B21 (early is the same as B20- not sure about later). It's just a hair longer (about 0.050) and has the same diameter and same wire gauge.
Anyway - If I was doing this over again, I'd just get a new pump. Why screw around with a used oil pump on a new engine? I spec'ed my pump and relapped the face of the pump (I've done it a thousand times with hydraulic pumps when I was younger) to get the groves out of the pump that I used and the gears were checked and were right on spec. That's why I didn't go with the new pump (that and sometimes I pinch the odd penny).
Coburn out.