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Discussion Starter #1
I thought I would post a couple of pictures of the parts I machined for doing the oil pump pressure relief valve modification.

I tapped the oil pump body with a 22 x 2.5 mm tap only because I already had it and it would work. If I was buying a tap to do this job I think I would step down on the thread pitch to 2.0mm so that it wasn't so coarse.

I machined the bushing from 1.0625 dia. 6061 alum. and tapped the hole for the set screw 5/16 18. The set screw spring seat is made from drill rod. The ball bearing dia. is .750 inches

I adjusted the oil pressure by mounting the pump in a 2L front cover that I had modified by blocking off the oil filter mount and tapping the injection pump oil galley for a pressure gauge fitting. I then mounted the front cover to an Alfetta pan with a qt. of oil in it and drove the oil pump with a distributer with the advance mechanism removed powered by a half inch drill. Since this pump was going in the Lemons car which has a stock motor I adjusted the pump for about 90psi max.
 

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Discussion Starter #3
Screen Size

I hadn't thought about increasing the screen size. Are you talking about making a larger pick up or increasing the size of the holes in the existing pick up?
 

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Increasing the hole size.
Take a look at Paul Spruell's site to see how Jim Steck did it (I'm assuming it's still there).
Ed
 

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Discussion Starter #6
Oil pump bolt removal

If the oil pan is off the motor I use a box end wrench, but it sounds like you are trying to get the pump off the motor with a bat wing oil pan with just the bottom off the pan. If I remember correctly even if you get all the bolts out the pump hits the baffle inside the oil pan. I know it's a pain but I'm pretty sure you need to pull the oil pan.

Wes
 

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Are you going to offer pumps in exchange? Or sell this as a kit? I would be interested in a couple of these for my engines. I would like to see a pressure of 70 psi hot. Not sure how that would translate out to a pressure in a cold setting.
 

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any one know rite off hand what shims i would need for my valves, i have a 74 alfa, 2000.
i assumed it all stock, so would need to know the size shims, i forgot them when i ordered the other parts
 

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After looking at this thread a 2nd time, I have a thought about the screw in portion to the oil pump body. The original uses a cotter pin to retain the cover over the spring. What will prevent the new plug from backing out of the pump body? I was thinking that I would most likely use some Loctite Blue or use a very small allen head set screw with a tapered point in one of the holes. I can only imagine that some miles down the highway in some odd location, the plug finally backs itself out and falls out leaving you with out oil pressure. Of course, if the plug was backing itself out, the oil pressure would be on the decline anyway, necessitating removing the pan to find out why.

What does Spruell use for an oil screen pickup? More oil flow into the pump is a good thing. :)

Shims? For what? There are no shims in the oil pump.
 

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I would safety wire which is what Spruell does. I used hardware cloth on my pump inlet, I think the holes were 1/8 or 1/4 square.
 

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Discussion Starter #15 (Edited)
Threaded oil pump plug

When I put the first oil pump I modified together I used Blue Loctite on the threads. We ended up breaking the distributer drive at the next race and had to change the pump. When I went to take the broken oil pump apart so I could modify another pump the cap didn't want to come off. It took alot of force to break the Loctite free. I thought about safety wiring them but hadn't done it yet.
I wasn't planning on offering these as kits but figured I could do pumps that people sent me. The most time consuming part is setting the pump up in the mill and threading the hole for the plug, machining the end of the bore perpendicular to the bore so that end cap has a flat surface to seat on. I machine the bottom of the bore with a 3/4 ball end mill so that the bearing sits in a conical seat. I figure it takes me about an 1.5 hours per pump by the time I machine everything, clean the pump, assemble and set the pressure.
 

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Me too. I put the distributor drive dog on the bottom of the distributor shaft in backward. It seemed to fit fine. but it was torquing the shaft sideways just a bit. Only took a few hundred miles to fail the pump drive shaft.

The dog ears and the slot in the pump shaft top are only a little bit off center. with a bit of wear, you can JUST get them to assemble wrong. Broken pump shaft waiting to happen.

The tough bit is that when the shaft breaks, the car is DOR immediately - the distributor stops turning. I was in a nasty part of Downtown San Jose at 11:30 pm, and AAA didn't even want to come there......

Robert
 
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