ONAN oil leak repairs

G

grant schaffer

New member
Sep 5, 2013
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SO when I turn on my ONAN I have oil dripping a spewing out everywhere. For fear of removal is there a rebuild kit and a rebuild manual for the ONAN.
I hope the block or cylinder head is not cracked but I would like to order the parts before tearing it our of the coach.

Any links?

thanks
--
1974 GMC Sequoia 26'
 
There are basic places they leak from.
As far as a kit , that does not exist from ONAN, might find some source.
Start with the Oil filter adapter as that is themost common place. You can
re torque the heads.
We can send you copies of the service manual via email

On Thu, Nov 7, 2019 at 3:04 PM Grant Schaffer via Gmclist <

> SO when I turn on my ONAN I have oil dripping a spewing out everywhere.
> For fear of removal is there a rebuild kit and a rebuild manual for the
> ONAN.
> I hope the block or cylinder head is not cracked but I would like to order
> the parts before tearing it our of the coach.
>
> Any links?
>
> thanks
> --
> 1974 GMC Sequoia 26'
>
>
> _______________________________________________
> 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
http://www.appliedgmcrvparts.com
1-800-752-7502
 
Do you get the GMCMI magazine? If not you can read it online at GMCMI.com.
I wrote an article about Onan oil leaks in the last issue.
Not difficult to fix. If you can’t find the article let me know and I’ll send it to you.

Emery Stora
77 Kingsley
Frederick,CO

>
> SO when I turn on my ONAN I have oil dripping a spewing out everywhere. For fear of removal is there a rebuild kit and a rebuild manual for the ONAN.
> I hope the block or cylinder head is not cracked but I would like to order the parts before tearing it our of the coach.
>
> Any links?
>
> thanks
> --
> 1974 GMC Sequoia 26'
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Do not make the same mistake that I did. I had oil spewing from everywhere. I determined that the oil must be coming from the seal on the crank and
was getting blow around. I got the seal and started to clean up everything and replace the seal. Luckily someone said "check the oil filter
adapter". I tightened the two mounting bots and fixed the problem. I gave the crank seal to someone who also misdiagnosed their problem and
eventually tightened their oil filter mounting to fix their problem. I do not know who has that new and uninstalled seal now but the last I knew it
was making the rounds in the GMC community. i
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
We repair ONAN units with leaks and find 90% to be from the oil adapter .
Do that first as you will have more than a handful if you start to reseal
everything.

On Fri, Nov 8, 2019 at 1:35 AM Ken Burton via Gmclist <

> Do not make the same mistake that I did. I had oil spewing from
> everywhere. I determined that the oil must be coming from the seal on the
> crank and
> was getting blow around. I got the seal and started to clean up
> everything and replace the seal. Luckily someone said "check the oil filter
> adapter". I tightened the two mounting bots and fixed the problem. I gave
> the crank seal to someone who also misdiagnosed their problem and
> eventually tightened their oil filter mounting to fix their problem. I do
> not know who has that new and uninstalled seal now but the last I knew it
> was making the rounds in the GMC community. i
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
>
> _______________________________________________
> 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
http://www.appliedgmcrvparts.com
1-800-752-7502
 
> Do not make the same mistake that I did. I had oil spewing from everywhere. I determined that the oil must be coming from the seal on the crank
> and was getting blow around. I got the seal and started to clean up everything and replace the seal. Luckily someone said "check the oil filter
> adapter". I tightened the two mounting bots and fixed the problem. I gave the crank seal to someone who also misdiagnosed their problem and
> eventually tightened their oil filter mounting to fix their problem. I do not know who has that new and uninstalled seal now but the last I knew it
> was making the rounds in the GMC community.

Just grins, I am going to throw in here too.

I have run into a handful of oily Onans. Most have been the oil filter adapter. Some just needed tightening, but I remember two that needed the two
gaskets replaced. (There are to with a plate between.) That plate can be cleaned a reused. Then there was one with a cracked filter adapter. I
want you to believe I was on that right away. Because the cooling fan draws the air over the cylinders, it will also draw the leaked oil off the
adapter and redistribute it all over the place.

There is one other good place to check, but it requires care. There is a large timing cover plate that is behind flywheel. Twice, I have been able
to snug up the dozen or so little screws and get the leak to stop. The CAREFUL is about remounting the flywheel. They are really easy to over torque
and crack.

With a little care, that Onan under the bed can be your friend a very long time.

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
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