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[GMCnet] Radiator Oil & Transmission Cooler Connections [message #325706] Fri, 03 November 2017 14:36 Go to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
G'day,

I want to double check the connections to the oil and transmission coolers in the radiator, IIRC the oil cooler is 1/2 inch inverted
flare and the transmission cooler is 3/8 inch inverted flare or is it 5/16 inch inverted flare?

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808
 



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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: [GMCnet] Radiator Oil & Transmission Cooler Connections [message #325721 is a reply to message #325706] Fri, 03 November 2017 19:11 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
Rob,
The Oil is correct.
The trans std is the smaller.

On Fri, Nov 3, 2017 at 12:36 PM, Rob Mueller
wrote:

> G'day,
>
> I want to double check the connections to the oil and transmission coolers
> in the radiator, IIRC the oil cooler is 1/2 inch inverted
> flare and the transmission cooler is 3/8 inch inverted flare or is it 5/16
> inch inverted flare?
>
> Regards,
> Rob M.
> The Pedantic Mechanic
> Sydney, Australia
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
> USA '77 Kingsley - TZE 267V100808
>
>
>
>
> _______________________________________________
> 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
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Radiator Oil & Transmission Cooler Connections [message #325722 is a reply to message #325706] Fri, 03 November 2017 19:12 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
The fitting at the radiator is 3/8, bit the nut is a weird one.

On Fri, Nov 3, 2017 at 5:11 PM, Jim Kanomata wrote:

> Rob,
> The Oil is correct.
> The trans std is the smaller.
>
> On Fri, Nov 3, 2017 at 12:36 PM, Rob Mueller
> wrote:
>
>> G'day,
>>
>> I want to double check the connections to the oil and transmission
>> coolers in the radiator, IIRC the oil cooler is 1/2 inch inverted
>> flare and the transmission cooler is 3/8 inch inverted flare or is it
>> 5/16 inch inverted flare?
>>
>> Regards,
>> Rob M.
>> The Pedantic Mechanic
>> Sydney, Australia
>> AUS '75 Avion - The Blue Streak TZE365V100428
>> USA '75 Avion - Double Trouble TZE365V100426
>> USA '77 Kingsley - TZE 267V100808
>>
>>
>>
>>
>> _______________________________________________
>> 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
>



--
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] Radiator Oil & Transmission Cooler Connections [message #325723 is a reply to message #325706] Fri, 03 November 2017 19:43 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
Senior Member
Rob,

IIRC, the OEM transmission line is 5/16", but, as Jim K says, with a weird
nut at the cooler -- because the cooler fitting is 3/8". That's what
allows us to replace the OEM 5/16" lines with 3/8" by changing the fitting
at the transmission from 5/16" inverted flare x 3/8' straight thread to
3/8" inverted flare x 3/8" straight thread

​Manny delivers the unusual 3/8" inverted flare x 3​/8" straight thread
adapter with his TH425 rebuilds.

Ken H.


On Fri, Nov 3, 2017 at 3:36 PM, Rob Mueller wrote:

> G'day,
>
> I want to double check the connections to the oil and transmission coolers
> in the radiator, IIRC the oil cooler is 1/2 inch inverted
> flare and the transmission cooler is 3/8 inch inverted flare or is it 5/16
> inch inverted flare?
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Radiator Oil & Transmission Cooler Connections [message #325724 is a reply to message #325723] Fri, 03 November 2017 23:07 Go to previous messageGo to next message
Kosier is currently offline  Kosier   United States
Messages: 834
Registered: February 2008
Karma: 1
Senior Member
Ken,

I think you'll find those fittings in the transmission are 1/4" straight
pipe thread.
The reason for the odd sized fitting at the radiator cooler is because GM
used
3/8" cooler lines up through 1972. When they dropped to 5/16", it was easy
enough to use the correct fittings at the transmission, but it would have
cost
money to retool the cooler in the radiator. And, of course, if it turned
out that
they had made a mistake, it would have cost even more to go back. Funny!

Gary Kosier
77PB w/500Cad
Newark, Ohio

--------------------------------------------------
From: "Ken Henderson"
Sent: Friday, November 03, 2017 8:43 PM
To: "GMC Mail List"
Subject: Re: [GMCnet] Radiator Oil & Transmission Cooler Connections

> Rob,
>
> IIRC, the OEM transmission line is 5/16", but, as Jim K says, with a weird
> nut at the cooler -- because the cooler fitting is 3/8". That's what
> allows us to replace the OEM 5/16" lines with 3/8" by changing the fitting
> at the transmission from 5/16" inverted flare x 3/8' straight thread to
> 3/8" inverted flare x 3/8" straight thread
>
> ​Manny delivers the unusual 3/8" inverted flare x 3​/8" straight thread
> adapter with his TH425 rebuilds.
>
> Ken H.
>
>
> On Fri, Nov 3, 2017 at 3:36 PM, Rob Mueller
> wrote:
>
>> G'day,
>>
>> I want to double check the connections to the oil and transmission
>> coolers
>> in the radiator, IIRC the oil cooler is 1/2 inch inverted
>> flare and the transmission cooler is 3/8 inch inverted flare or is it
>> 5/16
>> inch inverted flare?
>>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

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Re: [GMCnet] Radiator Oil & Transmission Cooler Connections [message #325725 is a reply to message #325724] Fri, 03 November 2017 23:26 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
We supply the 3/8Brass fitting for the trans with correct thread.

On Fri, Nov 3, 2017 at 9:07 PM, Gary Kosier wrote:

> Ken,
>
> I think you'll find those fittings in the transmission are 1/4" straight
> pipe thread.
> The reason for the odd sized fitting at the radiator cooler is because GM
> used
> 3/8" cooler lines up through 1972. When they dropped to 5/16", it was easy
> enough to use the correct fittings at the transmission, but it would have
> cost
> money to retool the cooler in the radiator. And, of course, if it turned
> out that
> they had made a mistake, it would have cost even more to go back. Funny!
>
> Gary Kosier
> 77PB w/500Cad
> Newark, Ohio
>
> --------------------------------------------------
> From: "Ken Henderson"
> Sent: Friday, November 03, 2017 8:43 PM
> To: "GMC Mail List"
> Subject: Re: [GMCnet] Radiator Oil & Transmission Cooler Connections
>
>
> Rob,
>>
>> IIRC, the OEM transmission line is 5/16", but, as Jim K says, with a weird
>> nut at the cooler -- because the cooler fitting is 3/8". That's what
>> allows us to replace the OEM 5/16" lines with 3/8" by changing the fitting
>> at the transmission from 5/16" inverted flare x 3/8' straight thread to
>> 3/8" inverted flare x 3/8" straight thread
>>
>> ​Manny delivers the unusual 3/8" inverted flare x 3​/8" straight thread
>> adapter with his TH425 rebuilds.
>>
>> Ken H.
>>
>>
>> On Fri, Nov 3, 2017 at 3:36 PM, Rob Mueller
>> wrote:
>>
>> G'day,
>>>
>>> I want to double check the connections to the oil and transmission
>>> coolers
>>> in the radiator, IIRC the oil cooler is 1/2 inch inverted
>>> flare and the transmission cooler is 3/8 inch inverted flare or is it
>>> 5/16
>>> inch inverted flare?
>>>
>>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>>
> _______________________________________________
> 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
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Radiator Oil & Transmission Cooler Connections [message #325731 is a reply to message #325706] Sat, 04 November 2017 09:29 Go to previous messageGo to next message
Larry is currently offline  Larry   United States
Messages: 2875
Registered: January 2004
Location: Menomonie, WI
Karma: 10
Senior Member
It is important to know that there are two fittings that could fit into the transmission for conversion from 5/16 to 3/8 cooler line. The correct one (don't have the sizes with me right now) the correct one has straight threads to match with the straight threads in the trans case and utilizes a soft metal washer for sealing. The WRONG adaptor fitting has tapered pipe threads and is intended to match to a female tapered pipe thread hole. Since the fitting in the trans is straight, it is not a match for the tapered adaptor. It may seem to work when you first screw it into the transmission, and seems like it will tighten and seal, but if you force it, you run the risk of that the tapered adaptor will put enough force on the trans case and could crack the trans case. If that happens, you're screwed.

Additionally, if you make the change to 3/8 with the proper straight adaptor, you must be careful not to over tighten it. Over tightening it runs the risk of stripping the soft aluminum in the transmission. I don't know what the proper torque is for that fitting. Find out before you tighten it down. Jimmy K has the proper adaptor. JMHO


Larry Smile
78 Royale w/500 Caddy
Menomonie, WI.

[Updated on: Sat, 04 November 2017 09:31]

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Re: [GMCnet] Radiator Oil & Transmission Cooler Connections [message #325732 is a reply to message #325731] Sat, 04 November 2017 09:58 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
This topic of the correct fitting for converting to a 3/8 line was
addressed in 1996 at International Convention.
One of the guys announced that Jim K had them. I started selling them, then
my source dried up, Gary Kener, our parts guy found the correct ones the
other month and we supply them with our 3/8 tran line kit and also sell
them separately.
For a while I would use a Die and recut the threads.

On Sat, Nov 4, 2017 at 7:29 AM, Larry wrote:

> It is important to know that there are two fittings that could fit into
> the transmission for conversion from 5/16 to 3/8 cooler line. The correct
> one
> (don't have the sizes with me right now) the correct one has straight
> threads to match with the straight threads in the trans case and utilizes a
> soft
> metal washer for sealing. The WRONG adaptor fitting has tapered pipe
> threads and is intended to match to a female tapered pipe thread hole.
> Since the
> fitting in the trans is straight, it is not a match for the tapered
> adaptor. It may seem to work when you first screw it into the transmission,
> and
> seems like it will tighten and seal, but if you force it, you run the risk
> of that the tapered adaptor will put enough force on the trans case and
> could crack the trans case. If that happens, you're screwed.
>
> Additionally, if you make the change to 3/8 with the proper straight
> adaptor, you must be careful not to over tighten it. Over tightening it
> runs the
> risk of stripping the soft aluminum in the transmission. I don't know what
> the proper torque is for that fitting. Find out before you tighten it down.
> JMHO
> --
> Larry
> 78 Royale w/500 Caddy
> Menomonie, WI.
>
> _______________________________________________
> 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
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Radiator Oil & Transmission Cooler Connections [message #325762 is a reply to message #325731] Sat, 04 November 2017 20:43 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
G'day,

I measured the tubing and nuts on the Kingsley's radiator today and compared the measurements to inverted flare nut drawings on
McMaster - Carr.

Transmission cooler 3/8" inverted flare nuts:

https://www.mcmaster.com/#6432t137/=1a46bw3

Engine oil cooler 1/2" inverted flare nuts:

https://www.mcmaster.com/#6432t138/=1a46cgx

I have ordered fittings that mate to the HotFlush system's QD's so I can bring an aluminum radiator I bought from Larry Weidner and
an OEM radiator that Scott Nutter gave me to a transmission shop and have them clean them.

I will instruct the transmission shop to flush the contamination that collects on the HotFlush machines filter screen into a plastic
food box so I can spread it on a piece of white paper and photograph it.

I wish I was still working at NASA we had microscopes that we would put contamination cleaned out of the Portable Life Support
System and examine it to determine what it was and the size.

I will examine the ports in the transmission tomorrow and report what I find.

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808

-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Larry
Sent: Saturday, November 4, 2017 9:29 AM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Radiator Oil & Transmission Cooler Connections

It is important to know that there are two fittings that could fit into the transmission for conversion from 5/16 to 3/8 cooler
line. The correct one (don't have the sizes with me right now) the correct one has straight threads to match with the straight
threads in the trans case and utilizes a soft metal washer for sealing. The WRONG adaptor fitting has tapered pipe threads and is
intended to match to a female tapered pipe thread hole. Since the fitting in the trans is straight, it is not a match for the
tapered adaptor. It may seem to work when you first screw it into the transmission, and seems like it will tighten and seal, but if
you force it, you run the risk of that the tapered adaptor will put enough force on the trans case and could crack the trans case.
If that happens, you're screwed.

Additionally, if you make the change to 3/8 with the proper straight adaptor, you must be careful not to over tighten it. Over
tightening it runs the risk of stripping the soft aluminum in the transmission. I don't know what the proper torque is for that
fitting. Find out before you tighten it down.

JMHO
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.



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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: [GMCnet] Radiator Oil & Transmission Cooler Connections [message #325933 is a reply to message #325732] Sat, 11 November 2017 09:39 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
G'day,

I measured the tubing and nuts on the Kingsley's radiator and compared the measurements to inverted flare nut drawings on McMaster -
Carr.

Transmission cooler 3/8" inverted flare nuts:

https://www.mcmaster.com/#6432t137/=1a46bw3

Engine oil cooler 1/2" inverted flare nuts:

https://www.mcmaster.com/#6432t138/=1a46cgx

I will buy nuts and make up short pieces of tube that will mate with the radiator and the male QD's that come with the HotFlush
machine.

I will instruct the transmission shop to flush the contamination that collects on the HotFlush machines filter screen into a plastic
food box so I can spread it on a piece of white paper and examine it. If feasible I'll photograph it as well.

I wish I was still working at NASA as we had microscopes that we would put contamination cleaned out of the Portable Life Support
System and examine it to determine what it was and its size.

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808



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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: [GMCnet] Radiator Oil & Transmission Cooler Connections [message #325934 is a reply to message #325933] Sat, 11 November 2017 10:37 Go to previous messageGo to next message
Cesar Carrasco is currently offline  Cesar Carrasco   United States
Messages: 30
Registered: September 2017
Location: Riverside, California
Karma: 0
Member
Rob, does it matter that the nuts are for copper and brass tubing?

On Sat, Nov 11, 2017 at 7:39 AM, Rob Mueller
wrote:

> G'day,
>
> I measured the tubing and nuts on the Kingsley's radiator and compared the
> measurements to inverted flare nut drawings on McMaster -
> Carr.
>
> Transmission cooler 3/8" inverted flare nuts:
>
> https://www.mcmaster.com/#6432t137/=1a46bw3
>
> Engine oil cooler 1/2" inverted flare nuts:
>
> https://www.mcmaster.com/#6432t138/=1a46cgx
>
> I will buy nuts and make up short pieces of tube that will mate with the
> radiator and the male QD's that come with the HotFlush
> machine.
>
> I will instruct the transmission shop to flush the contamination that
> collects on the HotFlush machines filter screen into a plastic
> food box so I can spread it on a piece of white paper and examine it. If
> feasible I'll photograph it as well.
>
> I wish I was still working at NASA as we had microscopes that we would put
> contamination cleaned out of the Portable Life Support
> System and examine it to determine what it was and its size.
>
> Regards,
> Rob M.
> The Pedantic Mechanic
> Sydney, Australia
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
> USA '77 Kingsley - TZE 267V100808
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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Re: [GMCnet] Radiator Oil & Transmission Cooler Connections [message #325936 is a reply to message #325934] Sat, 11 November 2017 14:03 Go to previous message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Cesar,

Nope, they will only be connected for the cleaning process (hours).

Over a long period there can be problems with dissimilar metal corrosion but in this case it's not a problem.

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808


-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Cesar Carrasco
Sent: Saturday, November 11, 2017 10:37 AM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Radiator Oil & Transmission Cooler Connections

Rob, does it matter that the nuts are for copper and brass tubing?



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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
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