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[GMCnet] Aluminum radiator [message #61215] Thu, 22 October 2009 20:14 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 have an aluminum radiator that I intend to install in The Blue Streak when
I fit the Caddy 500 engine.

Recently there has been some info published stating that this radiator is
more susceptible to damage from electrolysis than the standard radiator.

IIRC the radiator in a GMC sits on two rubber pads at the bottom; there are
two rubber pads at the top and it's connected to the engine via rubber
hoses.

From where I sit that means it is insulated from electrical currents or do
electrical currents run through the water?

What can I do to prevent damage from electrolysis?

Thanks,
Rob Mueller
Sydney, Australia
AUS '75 Avion-The Blue Streak TZE365V100428
USA '75 Avion-Double Trouble TZE365V100426

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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] Aluminum radiator [message #61218 is a reply to message #61215] Thu, 22 October 2009 20:49 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
Senior Member
I just typed a long response and accidently hit the wrong button on the mouse on the airport computer. I lost everything I typed.

When I get home tonight I'll send you two pages concerning radiator grounding from the grounding seminar I did at the Eastern States Rally.

I'm going back now to pulling #1 cylinder on my airplane.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Aluminum radiator [message #61234 is a reply to message #61215] Thu, 22 October 2009 21:31 Go to previous messageGo to next message
Gary Worobec is currently offline  Gary Worobec   United States
Messages: 867
Registered: May 2005
Karma: -1
Senior Member
Rob,
In the directions when you install it Gene gives instruction on how to check
for stray current and what the limits are. I think it needs to be less than
1/2 volt and you are OK.

Thanks,

Gary Worobec
Director, Product Development
PAXTON/PATTERSON
(O) 951-763-0518
(C) 773-230-6226
gtw5@earthlink.net
www.paxtonpatterson.com
----- Original Message -----
From: "Rob Mueller" <robmueller@iinet.net.au>
To: <gmclist@temp.gmcnet.org>
Sent: Thursday, October 22, 2009 6:14 PM
Subject: [GMCnet] Aluminum radiator


G'day,

I have an aluminum radiator that I intend to install in The Blue Streak when
I fit the Caddy 500 engine.

Recently there has been some info published stating that this radiator is
more susceptible to damage from electrolysis than the standard radiator.

IIRC the radiator in a GMC sits on two rubber pads at the bottom; there are
two rubber pads at the top and it's connected to the engine via rubber
hoses.

From where I sit that means it is insulated from electrical currents or do
electrical currents run through the water?

What can I do to prevent damage from electrolysis?

Thanks,
Rob Mueller
Sydney, Australia
AUS '75 Avion-The Blue Streak TZE365V100428
USA '75 Avion-Double Trouble TZE365V100426

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Re: [GMCnet] Aluminum radiator [message #61238 is a reply to message #61215] Thu, 22 October 2009 21:46 Go to previous messageGo to next message
shawnee is currently offline  shawnee   United States
Messages: 422
Registered: February 2004
Location: NC
Karma: 0
Senior Member
Rob,

You need to check for electrolysis when you install and fill your new radiator. It is a common misconception that aluminum radiators are more susceptable to electrolysis. Actually there is not a noticible difference. If you look at the back of a copper or brass radiator you will probably see green streaks coming down the core. This is the result of electrolysis which causes pin holes in the metal and ends up with a leaking radiator.

To start with, NEVER GROUND THE RADIATOR. This will void the aluminum radiator warrantee. You want the radiator to be the same potential as the engine block. The transmission and oil cooling lines will ground the radiator with the engine block since the radiator is isolated with the rubber mounts. Next turn on all the 12 volt lights and appliances. With the engine running and a full radiator you can check for electrolysis by using a digital volt meter. Touch the black lead to the battery negative terminal. Next touch the red lead to the coolant at the fill nozzle. If the result is more than 0.10 volts you have an electrical current flowing through the system. Do not touch the radiator. Check the voltage also at the engine and frame by touching the red lead to the coolant and the black lead to the engine and the frame. You can check for the faulty electrical source by continuing to touch the coolant and battery negative while having some one turn off the different 12 volt usages. If you see a drop in voltage then a faulty ground exists.

If any one is interested, let me know and I can email a detailed procedure on this. The other criteri for long radiator life is to change the coolant on a 3 to 5 year schedule. The corrosion inhibitors do not last forever. Their job is to attack corrosion and in turn they are disabled. When they are all gone then the radiatior takes the brunt of the corrosion.

Robert Mueller wrote on Thu, 22 October 2009 21:14

G’day,

I have an aluminum radiator that I intend to install in The Blue Streak when
I fit the Caddy 500 engine.

Recently there has been some info published stating that this radiator is
more susceptible to damage from electrolysis than the standard radiator.

IIRC the radiator in a GMC sits on two rubber pads at the bottom; there are
two rubber pads at the top and it's connected to the engine via rubber
hoses.

From where I sit that means it is insulated from electrical currents or do
electrical currents run through the water?

What can I do to prevent damage from electrolysis?

Thanks,
Rob Mueller
Sydney, Australia
AUS '75 Avion-The Blue Streak TZE365V100428
USA '75 Avion-Double Trouble TZE365V100426

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Gene Dotson
74 Canyonlands
www.bdub.net/Motorhome_Enhancements New Windows and Aluminum Radiators
Re: [GMCnet] Aluminum radiator [message #61241 is a reply to message #61238] Thu, 22 October 2009 23:13 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
Senior Member
Rob,

There is no need for me to send you the seminar material. Gene has stated the same thing I put in the seminar slides.

.1 volt or less is the spec. If it is more go around turning off things until you find what is causing the problem. Do not forget the engine driven alternator, converter, and isolator in your hunt.

Ken


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Aluminum radiator [message #61261 is a reply to message #61241] Fri, 23 October 2009 07:45 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
Gene / Ken,

Thanks for your responses; you have put my mind at ease. I printed out both
messages regarding this subject and put them in The Blue Streak project
folder.

Since I will be driving The Blue Streak on unimproved dirt roads in the
Outback I had decided to build a radiator guard even before I bought the
aluminum radiator. I reckon the guard that Blaine Merrill makes would
provide sufficient protection for any radiator on a GMC in the USA (I have
one on Double Trouble), however, I doubt that its Roo proof! ;-) I think
I'll make one that looks like a Venetian blind with slats 1" wide and 1/8'
thick with 1/2" spacing. I'll angle the slats so that they direct the
airflow into the radiator. In front of the slats I'll put the same screening
that Blaine uses to keep out stones. I'll attach it to the main frame on
both sides of the radiator. I reckon a radiator protector that beefy will
force anything I hit under the radiator instead of through it! Then again it
might slice it up! ;-)

Thanks,
Rob Mueller
Sydney, Australia
AUS '75 Avion-The Blue Streak TZE365V100428
USA '75 Avion-Double Trouble TZE365V100426

-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Ken Burton
Sent: Friday, 23 October 2009 3:14 PM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] Aluminum radiator

Rob,

There is no need for me to send you the seminar material. Gene has stated
the same thing I put in the seminar slides.

.1 volt or less is the spec. If it is more go around turning off things
until you find what is causing the problem. Do not forget the engine driven
alternator, converter, and isolator in your hunt.

Ken
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana


-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Gene Dotson
Sent: Friday, 23 October 2009 1:47 PM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] Aluminum radiator

Rob,

You need to check for electrolysis when you install and fill your new
radiator. It is a common misconception that aluminum radiators are more
susceptable to electrolysis. Actually there is not a noticible difference.
If you look at the back of a copper or brass radiator you will probably see
green streaks coming down the core. This is the result of electrolysis
which causes pin holes in the metal and ends up with a leaking radiator.

To start with, NEVER GROUND THE RADIATOR. This will void the aluminum
radiator warrantee. You want the radiator to be the same potential as the
engine block. The transmission and oil cooling lines will ground the
radiator with the engine block since the radiator is isolated with the
rubber mounts. Next turn on all the 12 volt lights and appliances. With
the engine running and a full radiator you can check for electrolysis by
using a digital volt meter. Touch the black lead to the battery negative
terminal. Next touch the red lead to the coolant at the fill nozzle. If
the result is more than 0.10 volts you have an electrical current flowing
through the system. Do not touch the radiator. Check the voltage also at
the engine and frame by touching the red lead to the coolant and the black
lead to the engine and the frame. You can check for the faulty electrical
source by continuing to touch the coolant and battery negative while having
some one turn off the different 12 volt usages. If you see a drop in
voltage then a faulty ground exists.

If any one is interested, let me know and I can email a detailed procedure
on this. The other criteri for long radiator life is to change the coolant
on a 3 to 5 year schedule. The corrosion inhibitors do not last forever.
Their job is to attack corrosion and in turn they are disabled. When they
are all gone then the radiatior takes the brunt of the corrosion.

--
Gene Dotson
74 Canyonlands
www.bdub.net/Motorhome_Enhancements

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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] Aluminum radiator [message #61278 is a reply to message #61215] Fri, 23 October 2009 09:08 Go to previous messageGo to next message
WayneB is currently offline  WayneB   Canada
Messages: 233
Registered: July 2008
Location: Ontario, Canada
Karma: 0
Senior Member
Using distilled water in the cooling system will reduce the amount of minerals that could eventually clog up the rad.

1976 23' GMCII By Explorer
Re: [GMCnet] Aluminum radiator [message #61618 is a reply to message #61278] Sun, 25 October 2009 18:14 Go to previous messageGo to next message
ggroth is currently offline  ggroth   United States
Messages: 282
Registered: February 2004
Location: Carson City NV
Karma: 0
Senior Member

I see that Summit Racing has a sacrificial anode in their catalog for alum. rad. Has anyone tried that or think it is worthwhile? I have on of Gene's rads and it works good.

geo groth '73 260 Sequoia Carson City Nevada 89703
Re: [GMCnet] Aluminum radiator [message #61636 is a reply to message #61618] Sun, 25 October 2009 20:03 Go to previous messageGo to next message
Tin Gerbil is currently offline  Tin Gerbil   United States
Messages: 236
Registered: October 2006
Location: Vancouver Island, B.C.
Karma: 0
Senior Member
George;
These anodes have been standard on expensive diesels for as long as I
can remember. Zinc on the saltwater side and magnesium on the fresh
water side of marine engines. Also magnesium on the raw water side in
brackish water. Just the magnesium in the land based engines. The way
to tell if they are working or not is to install one and monitor it. We
take them out and brush them with a SS brush to expose new clean metal
on a seasonal basis. If the anode is being rapidly eaten away, I would
look for the problem with grounding as outlined in KenB's post. Too
large a surface area of anodes will also cause corrosion with the
deposit ending up on the anode instead of the anode being sacrificed.

Gordon

George Groth wrote:
>
> I see that Summit Racing has a sacrificial anode in their catalog for
> alum. rad. Has anyone tried that or think it is worthwhile? I have
> on of Gene's rads and it works good.
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Gordon '74 Canyon Lands "Tin Gerbil" Vancouver Island, B.C.
Re: [GMCnet] Aluminum radiator [message #61851 is a reply to message #61636] Mon, 26 October 2009 20:51 Go to previous message
ggroth is currently offline  ggroth   United States
Messages: 282
Registered: February 2004
Location: Carson City NV
Karma: 0
Senior Member

Thanks Gordon, I may buy one and give it a try next summer.

geo groth '73 260 Sequoia Carson City Nevada 89703
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