Author Topic: external oil pump  (Read 242 times)

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Offline saluki42

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external oil pump
« on: 21 Jul 2020 at 07:03 »
Hi I'm after any information out there regarding the external twin gear pump fitted to my 34 Model Z. In  particular does any body have any details of what I can only assume used to be rubber seals fitted to 1 side of each of the four gears.

Chris

Offline Doug

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Re: external oil pump
« Reply #1 on: 22 Jul 2020 at 13:47 »
Chris,

I do not recall any seals in these pumps, either on the sides of the gears or the shafts.

-Doug

Offline saluki42

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Re: external oil pump
« Reply #2 on: 22 Jul 2020 at 14:29 »
Hi Doug, each of the gears has a recess into which in two cases, those facing out, a very age hardened rubber ring type seal was fitted and in one gear three fiber washers had been pushed. I thought this was to prevent leakage paths to outside world but maybe not.

Chris

Offline Doug

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Re: external oil pump
« Reply #3 on: 22 Jul 2020 at 15:28 »
Chris,

Oops, retraction time.

My 1934 ohv uses essentially the same oil pump, but it has been a long time since I had a look at it. I have a spare pump, so pulled the cover off it and had a look. At first it seemed to confirm my memory; a plain face to the end of the gear with a close axial fit in the housing to limit oil seepage.



Then I thought I might as well lift the idler gear out, erp...



The seals are felt, though the one looks like it my be a homemade replacement. It looks as if this is primarily intended to be a shaft seal between the delivery and scavenge chambers of the pump. This is the scavenge side. I did not open up the delivery side to see if used seals on both sides of those gears, or just one.

-Doug

Offline saluki42

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Re: external oil pump
« Reply #4 on: 26 Jul 2020 at 10:33 »
I think I have a bigger problem than missing seals now I've cleaned it for a closer look

 

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