J-McDonald

How much can I expect to pay for a new oil pump (including installation) on a '91 C2? From the engine diagram that I have (in Frere's book), it appears that the pump can be removed without removing the engine. Is this correct?

Adrian

Dear J,
Why are you considering changing your oil pump. Are you 100% sure it has failed. The oil system on the 964 is a bit of a wonder. Do you have no oil pressure, or too low oil pressure or what.
I have no idea how much they cost but they will not be cheap. Maybe you could consider a rebuilt version if they exist. A common problem of no oil pressure is a collapsed oil filter,
Ciao,
Adrian
911C4

Cupcar

Pump not removable in car. It is essentially the last component removed during a complete engine dissassembly.

J-McDonald

Thanks for your reply Adrian. Here's the situation -- the car (a '91 C2) was rear-ended (relatively lightly- decklid buckled, tailights cracked). When warm, the oil pressure gauge on the car reads between 1.25 and 1.5 at idle and 4.5-5.0 at speed. I received it back from the bodyshop and was driving it home and pulled up to a stoplight. As the rpm's dropped, the oil pressure level on the gauge dropped from 4.5-5.0 to the usual 1.25-1.5, but then dropped straight to zero (no trouble lights went off and the engine continued to run perfectly). I turned it off immediately. I then turned it back on, and it did it again. However, if I revved the engine, the needle on the oil pressure gauge would jerkily jump back to 1.25-1.5 and then hold that position at idle.

I had the car flat-bedded to the dealer, who will be looking at it later today or tomorrow.

I'm thinking that it could be the sending unit for the gauge, which may have been damaged in the accident. It also could be the oil pump. Since the car isn't leaking any oil, I would tend to doubt that it's a collapsed oil filter (but I'll have the dealer check it out).

By the way, within the last 200 miles, I had a compression test done - 175-180psi in all cylinders. However, I didn't get a leak-down test done (which I'm regretting now).

I'm trying to get a sense of how much I'm in for if it isn't just the gauge and the oil pump is shot.

Kevin

J-

If you did have a pump failure, and you had zero oil pressure, you mentioned that you revved the engine, your hydraulic tensioners would not have had enough oil pressure to put pressure against your chains. You would have heard alot of clanking.

Adrian

Dear J,
I would suspect damaged oil lines before a damaged pump. A full detailed visual inspection of the wiring and the plumbing is in order. Do not forget that the oil filter is mounted on the side away from the engine. The piping may well be damaged.
I checked the manuals and the oil pump under noraml circumstances requires and engine drop to remove. I very much doubt that your engine pump is damaged. I would suspect crimped pipes or damaged wiring,
Ciao,
Adrian
911C4