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Home » Public Forums » GMCnet » More oil bybass paths?? (Pump body and cooler adaptor? )
More oil bybass paths?? [message #285777] Mon, 24 August 2015 19:37 Go to next message
JohnL455 is currently offline  JohnL455   United States
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Registered: October 2006
Location: Woodstock, IL
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Senior Member
I was at Highway Stars over the weekend looking at some NOS Buick turbo parts on the shelf. The oil cooler adaptor is a "baby" version of the one GM used on the 455 Olds in a smaller form factor for V6 PF47/PF52 filter bases. I found the pintle type filter bypass in the pump exterior housing, which I imagine is a "baby" version of the Olds V8 type. The spring action is pretty gentle and that seems to be in keeping what has been found so far on the Olds. Then I started to study the screw on cooler adaptor and low and behold ther is another bypass valve on it that shunts the external hose loop. Do we have that as well?

John Lebetski
Woodstock, IL
77 Eleganza II
Re: [GMCnet] More oil bybass paths?? [message #285779 is a reply to message #285777] Mon, 24 August 2015 19:49 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Registered: July 2007
Location: Sydney, Australia
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Senior Member
John,

I've gone over the oil flow a "million" times and the only bypass is in the oil filter adapter that mounts to the side of the
engine.

UNLESS someone screws up and installs an oil filter with a built in bypass!

Regards,
Rob M.
The Pedantic Mechanic

-----Original Message-----
From: John R. Lebetski

I was at Highway Stars over the weekend looking at some NOS Buick turbo parts on the shelf. The oil cooler adaptor is a "baby"
version of the one GM used on the 455 Olds in a smaller form factor for V6 PF47/PF52 filter bases. I found the pintle type filter
bypass in the pump exterior housing, which I imagine is a "baby" version of the Olds V8 type. The spring action is pretty gentle and
that seems to be in keeping what has been found so far on the Olds. Then I started to study the screw on cooler adaptor and low and
behold ther is another bypass valve on it that shunts the external hose loop. Do we have that as well?
--
John


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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: More oil bybass paths?? [message #285789 is a reply to message #285777] Mon, 24 August 2015 21:38 Go to previous message
JohnL455 is currently offline  JohnL455   United States
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
Senior Member
That's why I was so surprised to see a second poppet type valve on the 2 hose add on cooler adaptor. I guess we have one less to be concerned with. Just will have to wait to see what testing revels. I'm interested to see if heavyweight oils lead to more bypass %. Carry on.

John Lebetski
Woodstock, IL
77 Eleganza II
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