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Oil Leak at water pump [message #322021] Sun, 13 August 2017 16:01 Go to next message
Justin Brady is currently offline  Justin Brady   United States
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This one's a bit weird.
I had a significant oil leak from the fuel pump gasket. Replaced it and all seemed well but there was still a little leaking.
Today I thoroughly degreased the engine and ran it for a while to see where the leak was coming from.
It's coming from the water pump/engine seal.
http://www.thegmcrv.com/wp-content/uploads/2017/08/IMG_20170813_144259.jpghttp://www.thegmcrv.com/wp-content/uploads/2017/08/IMG_20170813_144259.jpg

I've cleaned and verified the leak several times so I am sure that's where it's coming from.
I tightened the bolt above it and will see if that helps, but in the interim I wanted to get you guys educated opinion on it.

Seems to me there shouldn't be oil there? I need to look at the oil passage diagram but unless it's leaking through the bolt hole above it I'm not quite sure where it would be coming from.



Justin Brady http://www.thegmcrv.com/ 1976 Palm Beach 455
Re: Oil Leak at water pump [message #322022 is a reply to message #322021] Sun, 13 August 2017 16:02 Go to previous messageGo to next message
Justin Brady is currently offline  Justin Brady   United States
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Registered: April 2015
Location: Bell Buckle, TN
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I found this on the photo site:
http://www.gmcmhphotos.com/photos/discussion-photos/p52587-hole-in-front-oil-galley-plug.html

Perhaps my leak is the bolt hole?

Any tips for sealing it? Is there an O ring in there that may have deteriorated?


Justin Brady http://www.thegmcrv.com/ 1976 Palm Beach 455
Re: Oil Leak at water pump [message #322023 is a reply to message #322022] Sun, 13 August 2017 16:07 Go to previous messageGo to next message
Justin Brady is currently offline  Justin Brady   United States
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Leak appears to originate from here: (not my coach)
http://www.thegmcrv.com/wp-content/uploads/2017/08/water-pump.jpghttp://www.thegmcrv.com/wp-content/uploads/2017/08/water-pump.jpg


Justin Brady http://www.thegmcrv.com/ 1976 Palm Beach 455
Re: [GMCnet] Oil Leak at water pump [message #322033 is a reply to message #322023] Sun, 13 August 2017 18:21 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Justin,
If it was me, I would torque the bolts on the pump properly as that will
compress the gasket that was leaking.
I bet the water pumps main bolts were not tight after may miles.

On Sun, Aug 13, 2017 at 2:07 PM, Justin Brady wrote:

> Leak appears to originate from here: (not my coach)
> http://www.thegmcrv.com/wp-content/uploads/2017/08/water-pump.jpg
> --
> Justin Brady
> http://www.thegmcrv.com/
> 1976 Palm Beach 455
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Oil Leak at water pump [message #322034 is a reply to message #322033] Sun, 13 August 2017 18:37 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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There are two self tapping screws on the bottom of the water pump that
screw into the front timing cover. If they get over tightened (very likely)
they strip the threads and leak oil. Sometimes, they are just loose and not
stripped. In that case, remove them, coat the threads with non hardening
sealant and reassemble. Hope this helps.
Jim Hupy
Salem, Or
78 GMC ROYALE 403

On Aug 13, 2017 4:22 PM, "Jim Kanomata" wrote:

> Justin,
> If it was me, I would torque the bolts on the pump properly as that will
> compress the gasket that was leaking.
> I bet the water pumps main bolts were not tight after may miles.
>
> On Sun, Aug 13, 2017 at 2:07 PM, Justin Brady wrote:
>
>> Leak appears to originate from here: (not my coach)
>> http://www.thegmcrv.com/wp-content/uploads/2017/08/water-pump.jpg
>> --
>> Justin Brady
>> http://www.thegmcrv.com/
>> 1976 Palm Beach 455
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>
>
>
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk@appliedairfilters.com
> http://www.appliedgmc.com
> 1-800-752-7502
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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Re: Oil Leak at water pump [message #322035 is a reply to message #322021] Sun, 13 August 2017 18:52 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Location: St. Cloud, MN
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Senior Member
Timing cover is sandwiched between the water pump and the block. So it can leak oil about anywhere on the waterpump.

There is a timing cover gasket between the cover and block, and then the waterpump gasket between cover and water pump.

Jim hupy probably is correct, pull bolts out and rtv
Them and reinsert and
Torque.



Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: Oil Leak at water pump [message #322036 is a reply to message #322022] Sun, 13 August 2017 19:22 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Location: Hebron, Indiana
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If RTV does not work try aviation Permatex which is available at your favorite auto parts store.

I'm thinking you might have a leak at the front seam of the intake manifold which is slightly above where you are looking. Also what is the condition on the oil fill tube elbow?


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: Oil Leak at water pump [message #322038 is a reply to message #322036] Sun, 13 August 2017 20:02 Go to previous messageGo to next message
Justin Brady is currently offline  Justin Brady   United States
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Registered: April 2015
Location: Bell Buckle, TN
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Thanks guys.
The leak is definitely from the top as pictured not the bottom, as all testing was done while idling and not driving so wind shouldn't be blowing it upward.

Ken, that's a possibility as well.
Oil fill tube I cleaned and checked for leaks today, good there, but after driving today there is oil gathered around the base of the metal.fill tube, so either it went up (wind) or it's leaking from the tube junction.


Justin Brady http://www.thegmcrv.com/ 1976 Palm Beach 455
Re: Oil Leak at water pump [message #322080 is a reply to message #322023] Mon, 14 August 2017 11:34 Go to previous messageGo to next message
roy1 is currently offline  roy1   United States
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Location: Minden nevada
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If I had it torn down that far I would pull the timing cover inspect the timing chain for wear and put in new gaskets . Also time for a new crankshaft oil seal all are past due looking at your pictures.

Roy Keen Minden,NV 76 X Glenbrook
Re: Oil Leak at water pump [message #322081 is a reply to message #322080] Mon, 14 August 2017 11:36 Go to previous message
Justin Brady is currently offline  Justin Brady   United States
Messages: 769
Registered: April 2015
Location: Bell Buckle, TN
Karma: 11
Senior Member
Roy,
The torn down photo is not my coach.
56k miles on mine.


Justin Brady http://www.thegmcrv.com/ 1976 Palm Beach 455
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