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[GMCnet] Filling Cooling System [message #324440] Thu, 28 September 2017 22:28 Go to next message
k2gkk is currently offline  k2gkk   United States
Messages: 4452
Registered: November 2009
Karma: -8
Senior Member
I know that I have seen info on a means to totally fill the coolant system, but that was quite awhile back. My second episode with lack of cooling and subsequent knocking engine MAY have been caused by a leaking "freeze" plug. That has been corrected and my oil sample to Blackstone has been analyzed and reported as only a mild elevation in copper (32 ppm vs universal average of 24 ppm) and lead (54 ppm vs 39 ppm universal average). Neither was rated as excessive. No fuel, coolant, or moisture in the oil, either. Their statement was, "Overall, this is a good report."


I'd say that this says that I maybe or probably don't need an engine replacement. YIPPEE !


If I can get cooling system properly filled, I believe we will take the Money Pit out for a weekend at a nearby campground.


D C "Mac" Macdonald
Amateur Radio K2GKK
Since 30 November '53
USAF and FAA, Retired
Member GMCMI & Classics
Oklahoma City, OK
"The Money Pit"
TZE166V101966
'76 ex-Palm Beach
k2gkk + hotmail dot com

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Re: [GMCnet] Filling Cooling System [message #324441 is a reply to message #324440] Thu, 28 September 2017 22:54 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
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Senior Member

Mac,

Most mechanic's shops need to completely fill 'closed' cooling systems that are common on many later model cars. They typically use a vacuum system similar to evacuating an air conditioning system. You should be able to find someone locally who can perform this operation for you.

The old fashioned way is to fill the radiator and the coolant overflow reservoir, start the engine and bring it up to operating temperature, shut it off and let it cool down. The system will suck coolant out of the reservoir to fill the system. Repeat the above procedure until the reservoir level stabilizes.

Not to discourage you, but an overheated engine will often crack heads. Hopefully that did NOT happen to yours. If it did, a competent shop can do a top end job for you. Expect to pay somewhere around $3,000.00 to replace the heads.


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: [GMCnet] Filling Cooling System [message #324442 is a reply to message #324440] Fri, 29 September 2017 05:17 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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Registered: March 2004
Location: Americus, GA
Karma: 9
Senior Member
Mac,

Here's how I've rigged my cooling system for complete filling:
http://www.gmcmhphotos.com/photos/g4278-simple-2fno-spill-2fno-air-cooling-system-filler.html

Ken H.


On Thu, Sep 28, 2017 at 11:28 PM, D C _Mac_ Macdonald
wrote:

> ​...
>
> If I can get cooling system properly filled, I believe we will take the
> Money Pit out for a weekend at a nearby campground.
> ​...
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Filling Cooling System [message #324452 is a reply to message #324440] Fri, 29 September 2017 13:38 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Registered: January 2004
Location: Hebron, Indiana
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Senior Member
If you have an OEM water pump or a replacement water pump with at least a 4" impeller, refilling the cooling system is a no brainer.

I went out a couple of weeks ago to help a GMCer that blew a heater hose. While I was enroute the owner repaired the leak and obtained 3 gallons of replacement antifreeze. When I got there we filled the radiator and overflow bottle to the correct levels, warmed up the engine with the cap loose, and topped off the radiator. That was it. The heater hoses were hot so the heater was filled, and the owner drove away. I talked to the owner a week or so later and was told that the overflow bottle took less than 1 pint to bring it to the correct level after driving about 1500 miles in three days.

So fill it up, check it once after warmup, and drive it if you have the standard 4" or larger water pump.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Filling Cooling System [message #324453 is a reply to message #324452] Fri, 29 September 2017 14:52 Go to previous messageGo to next message
Justin Brady is currently offline  Justin Brady   United States
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Location: Bell Buckle, TN
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Senior Member
Yep mine was the same. Fill it, let the thermostat open, let it cool. Top it off. Done

Justin Brady http://www.thegmcrv.com/ 1976 Palm Beach 455
Re: [GMCnet] Filling Cooling System [message #324455 is a reply to message #324440] Fri, 29 September 2017 17:42 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Location: Woodstock, IL
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Be sure there are zero micro cracks in the overflow return hose. If it can suck any air it will not refill rafiator. Also inspect radiator cap well. If outer seal is worn or shifted and mushed, it may not pull coollant back in. Also check the spring and action on the center poppet valve. I recently had a poppet valve spring valve spring fail so cap would build zero pressure, even though pressure seal and spring were fine.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: [GMCnet] Filling Cooling System [message #324456 is a reply to message #324455] Fri, 29 September 2017 18:07 Go to previous messageGo to next message
k2gkk is currently offline  k2gkk   United States
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Thanks for the tipoff, John.

I totally replaced the overflow bottle and tubing AND (IIRC) the radiator cap with the proper 9.0 psi rating.


D C "Mac" Macdonald
Amateur Radio K2GKK
Since 30 November '53
USAF and FAA, Retired
Member GMCMI & Classics
Oklahoma City, OK
"The Money Pit"
TZE166V101966
'76 ex-Palm Beach
k2gkk + hotmail dot com


________________________________
From: Gmclist on behalf of John R.Lebetski
Sent: Friday, September 29, 2017 17:42
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Filling Cooling System

Be sure there are zero micro cracks in the overflow return hose. If it can suck any air it will not refill radiator. Also inspect radiator cap well.
If outer seal is worn or shifted and mushed, it may not pull coolant back in. Also check the spring and action on the center poppet valve. I recently
had a poppet valve spring valve spring fail so cap would build zero pressure, even though pressure seal and spring were fine.
--
John Lebetski
Woodstock, IL
77 Eleganza II


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Re: [GMCnet] Filling Cooling System [message #324462 is a reply to message #324456] Sat, 30 September 2017 00:25 Go to previous message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
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Senior Member
John,
You are 100% correct in suggesting to check the condition of the system.
Too bad most do not check it and wonder why radiator level goes down and
the reservoir stays full.
Over half of the coaches that come in for service are not functioning.

On Fri, Sep 29, 2017 at 4:07 PM, D C _Mac_ Macdonald
wrote:

> Thanks for the tipoff, John.
>
> I totally replaced the overflow bottle and tubing AND (IIRC) the radiator
> cap with the proper 9.0 psi rating.
>
>
> D C "Mac" Macdonald
> Amateur Radio K2GKK
> Since 30 November '53
> USAF and FAA, Retired
> Member GMCMI & Classics
> Oklahoma City, OK
> "The Money Pit"
> TZE166V101966
> '76 ex-Palm Beach
> k2gkk + hotmail dot com
>
>
> ________________________________
> From: Gmclist on behalf of John
> R.Lebetski
> Sent: Friday, September 29, 2017 17:42
> To: gmclist@list.gmcnet.org
> Subject: Re: [GMCnet] Filling Cooling System
>
> Be sure there are zero micro cracks in the overflow return hose. If it can
> suck any air it will not refill radiator. Also inspect radiator cap well.
> If outer seal is worn or shifted and mushed, it may not pull coolant back
> in. Also check the spring and action on the center poppet valve. I recently
> had a poppet valve spring valve spring fail so cap would build zero
> pressure, even though pressure seal and spring were fine.
> --
> John Lebetski
> Woodstock, IL
> 77 Eleganza II
>
>
> _______________________________________________
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> Gmclist Info Page - GMCnet mailman/listinfo/gmclist_list.gmcnet.org>
> list.gmcnet.org
> To see the collection of prior postings to the list, visit the Gmclist
> Archives. Using Gmclist: To post a message to all the list members, send
> email ...
>
>
>
> _______________________________________________
> GMCnet mailing list
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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
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