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PolarBear
10-24-2017, 07:56 PM
I took apart the oil pump I have to port it and I notice that the gerotor pieces have sharp edges. Does anyone know whether I should knock the edges off with a file, or will that reduce the output?
Also, does anyone know where to get a shim kit for the pump spring? It is a used pump, so I am not sure what pressure it will make, I am thinking of shimming it right off the bat, but I am not sure how much shim it would need

KirkEvil
10-25-2017, 12:02 PM
I took apart the oil pump I have to port it and I notice that the gerotor pieces have sharp edges. Does anyone know whether I should knock the edges off with a file, or will that reduce the output?
Also, does anyone know where to get a shim kit for the pump spring? It is a used pump, so I am not sure what pressure it will make, I am thinking of shimming it right off the bat, but I am not sure how much shim it would need

Don't knock the edges off. Also be aware those internal pump gears have a chamfer on one side but not the other. If you install them backwards they seize when the front cover is bolted down.

Use 2 standard thickness washers to shim the relief spring. That should give you about 45psi hot idle

PolarBear
10-25-2017, 12:15 PM
Don't knock the edges off. Also be aware those internal pump gears have a chamfer on one side but not the other. If you install them backwards they seize when the front cover is bolted down.

Use 2 standard thickness washers to shim the relief spring. That should give you about 45psi hot idle

Thanks for the reply. I took note on the way it came apart.

The spring is a small diameter, so the shim would go inside the cap or the plunger?

KirkEvil
10-25-2017, 12:55 PM
Thanks for the reply. I took note on the way it came apart.

The spring is a small diameter, so the shim would go inside the cap or the plunger?

Inside the cap. Basically you're adding preload to the stock spring to bump the relief pressure rather than replacing it with a higher rate spring.

unstable bob gable
10-25-2017, 02:59 PM
Why aren't you using a new oil pump?

PolarBear
10-25-2017, 03:43 PM
Why aren't you using a new oil pump?

There's nothing wrong with this one and I had it. The gerotor in the housing fit is still very tight, so the only other part to "wear" would be the bypass spring, and that is probably still good too, but with the shim it will put out a little more pressure. This design is very robust, so I am not worried about it failing, plus I'll have an Accusump on the car, so I shouldn't have to worry about anything :-P

unstable bob gable
10-25-2017, 04:04 PM
There's nothing wrong with this one and I had it. The gerotor in the housing fit is still very tight, so the only other part to "wear" would be the bypass spring, and that is probably still good too, but with the shim it will put out a little more pressure. This design is very robust, so I am not worried about it failing, plus I'll have an Accusump on the car, so I shouldn't have to worry about anything :-P

Oh.

PolarBear
10-28-2017, 10:46 AM
Use 2 standard thickness washers to shim the relief spring. That should give you about 45psi hot idle

The washers I found are a tiny bit too big in diameter to go in the cap, but I can kock the edges down with a file and they should drop right in. They are also about .029 in thickness, does that sound about right?

KirkEvil
10-28-2017, 08:05 PM
yeah that sounds about right

PolarBear
10-28-2017, 08:16 PM
yeah that sounds about right

Cool, thanks. I got the washed fit in the plug now. Tomorrow I will port it and put it back together.

unstable bob gable
10-29-2017, 11:31 AM
Polar bears rules!!!