1956 Cad oil pump coversion

[John Washburn CLC 1067 Sadly deceased.]

Folks,

Decided to go to the dark side and change out the vacuum wiper motors with a new electric two speed wiper motor. Very cool bolt in product.

But now I want to remove the vacuum pump from the oil pump but the plate is on the vacuum pump and will not work if you use it without the vacuum pump.

Looks like either the plate or the pump unit from 1959 to 1961 will work.

Anyone do this before or know who might have the later plate or pump???

The Johnny

[Roger Zimmermann]

I'm sure I have a '59 oil pump, if you would like to have the plate. Just pay for the shipping.

[cadman56]

Why couldn't you just remove the two vacuum pump vanes & associated spring & rod?

[John Washburn CLC 1067 Sadly deceased.]

Larry,

Would not work. The vacuum pump draws the oil thru the oil pump to create vacuum. So if it is not working there is a big leak down thru the vacuum pump - thus bearing problems (in my opinion).

The Johnny

[J. Gomez]

Johnny,

One alternative if you want to keep the OEM is to remove the hex shaft from the oil pump that drives the vacuum pump and place it back without the shaft. 

Just a cheap solution..! 

[John Washburn CLC 1067 Sadly deceased.]

Jose,

Was pondering that but not sure if it will not cause problems? Your thoughts...

The Johnny

[J. Gomez]

Johnny,

I do not believe it will the oil pump would function as normal but the vacuum pump will be inoperable. The only thing you will need to care for is to block the vacuum line from the side of the block that feeds the firewall manifold, so there is no reversed vacuum feedback on that line.

Good luck..!

[John Washburn CLC 1067 Sadly deceased.]

Jose,

Interesting. But I guess I wold have to block the line from the vacuum pump that would go to the line thru the block. Still not sure I might not have problems if the vacuum pump leaks???

I thing I will got with the later 59 thru 61 oil pump or plate if I can find one.

I am tooooo old to rebuild this again. Plus I need to get the 1938 Limo done...

The Johnny

[J. Gomez]

Johnny,

I’m not sure if the 59-60 pump would fit the shaft from the 1956 distributor and/or if the PSI are the same on both.

Since the vacuum pump will not be operational there would be no issues with leaking, just an observation.  Oil will be present on the vacuum pump but it should not be syphoned back into the vacuum line if you block the line at the valve on the side of the block or at the manifold on the firewall.

But I do agree it will be a PITA to get back there in case there is a problem.

Good luck..!

[cadman56]

Having rebuilt (3) of these pumps I had another thought-an extension of Mr. Gomez's thought-have a machine shop weld the small oil passages shut then mill the plate smooth.  However, won't the hole for the hex drive still pose a problem (leak)?  I have spare pumps in my garage so I will refresh my memory with one in hand in the morning.  I do think the 59-61 390 will work.  Larry

[John Washburn CLC 1067 Sadly deceased.]

Larry,

I believe you are correct. But let me know what you find. I have been wrong a lot lately.

The Johnny

[cadman56]

Hello John,
Here is what I found:  the plate has a circular slot which lines up with the vent hole that runs vertically through the oil pump body.  This slot would not need to be welded shut as it is isolated from the oil.  The plate does have the hole in the center for the hex drive & would need to be welded closed.  I think that would create too much heat on the plate.
Now, according to my Cadillac parts book dated by a REVISED MAY 1, 1973, I find:
Group 1.653  HOUSING, ENGINE OIL PUMP,  P/N 3632567, HOUSING W/drive shaft,  is the same for 54-60
Group 1.639  SHAFT, ENGINE OIL PUMP, P/N 1463387, SHAFT, drive, is the same for 56-62
Group 1.656  SCREEN, ENGINE OIL PICK UP AND STRAINER, P/N 1459843, SCREEN, w/pipe, is the same 54-60
Group 1.657  SEAL, ENGINE OIL PUMP INTAKE, P/N 1471905, SEAL, is the same for 50-60
Group 1.639  GEAR SET ENGINE OIL PUMP, P/N 3630434, GEAR SET w/shaft is for 54-58
                                                                P/N 3631360, GEAR SET w/shaft is for 59-62
I think you would be safe in using the 59 oil pump.
Hope this helps. 
I have a daughter living in Parker, CO.  Next time I am out there I will try to call.
Good luck, Larry

[John Washburn CLC 1067 Sadly deceased.]

Larry,

Great minds think alike.

Came to the same conclusion.

Come see us when you visit Parker only about 15 minutes away.

The Johnny

[CRAIG LEWIS]

John,

Ran across your post and am wondering how this all worked out for you. Did you use a 59 pump and did it work fine without any modifications. I am going to rebuild my 56 and eliminating the vacuum as well. Any ideas on getting a rebuilt 59 if that is the way to go?

Thanks
Craig

[Lexi]

John,

Ran across your post and am wondering how this all worked out for you. Did you use a 59 pump and did it work fine without any modifications. I am going to rebuild my 56 and eliminating the vacuum as well. Any ideas on getting a rebuilt 59 if that is the way to go?

Thanks
Craig

Sadly, John is no longer with us. Clay/Lexi