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[GMCnet] Fan? [message #325978] Mon, 13 November 2017 18:57 Go to next message
Arthur Mansfield is currently offline  Arthur Mansfield   United States
Messages: 290
Registered: April 2010
Karma: 0
Senior Member
I have 76 and the fan runs when ever the key is on. It sounds like the fan has gone bad. I would like to unhook the wire that connected to the fan when they is on. If I remember I need to disconnect the red wire but it has been a long time since I read how to disconnect the fan when the key is on. I was charging the battery and turned the key on and was surprise that the voltage was so low. Charger was set to 10 amps and the fan was dropping the voltage about 1.5 volts. So that is way to high so the fan needs to go. I need to rebuild the heater and the AC system if I am going to use the RV much. Looks like a lot of work.

Had not planned to use the RV this year and now we are heading out to visit my wife uncle who’s cancer and is not doing to good. Tried to take the car but she wanted to go in the RV. So will be heading out in coupler days. I have done a few things on the RV but it really needs more tender loving care than it got this year. Next year I know I will be making my every other trip to up state NY. That one I look forward to as we stay next to lake and my wife favorite eating place. This time we will be going to another high school graduation.

I started to grease the RV and could not get my grease gun to work. Everything is normal for me when I decided to pull out the RV. Last year it was a bad alternator that quit the day before I was getting ready to leave. A week earlier it was fine when I took the RV for a ride to check it out.

Art
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Re: [GMCnet] Fan? [message #325981 is a reply to message #325978] Mon, 13 November 2017 19:26 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
Art,

Quite aside from the question of whether you need a new blower motor,
there's the fact that the fan always runs when the key is on. That's a
design feature intended to keep the cockpit ventilated. Most of us figure
that after 40 years, the cockpit will ALWAYS be ventilated. So, many of us
make very simple modification that defeats the always-running blower: At
the left (driver's) side of the HVAC box under the hood, near the firewall
and the bottom of the box, there's a multi-wire connector which feeds the
blower speed resistor pack onto which it's plugged. One of the wires into
that connector is Yellow. If you do ONE of the following 3 tricks, you'll
defeat the run-with-ignition feature, leaving all other functions of the
blower switch unchanged: 1. Cut the yellow wire, 2. Remove that wire
from the connector, or 3. Unplug the connector, bend that pin over on the
mating male connector, then re-attach the removed connector. In simpler
words, disconnect that yellow wire.

​For some later modification, that disconnected yellow wire may prove
useful, since it's always "hot" when the ignition is "On".​

Ken H.


On Mon, Nov 13, 2017 at 7:57 PM, 1104agm wrote:

> I have 76 and the fan runs when ever the key is on. It sounds like the
> fan has gone bad. I would like to unhook the wire that connected to the
> fan when they is on. If I remember I need to disconnect the red wire but
> it has been a long time since I read how to disconnect the fan when the key
> is on. I was charging the battery and turned the key on and was surprise
> that the voltage was so low. Charger was set to 10 amps and the fan was
> dropping the voltage about 1.5 volts. So that is way to high so the fan
> needs to go. I need to rebuild the heater and the AC system if I am going
> to use the RV much. Looks like a lot of work.
>
> Had not planned to use the RV this year and now we are heading out to
> visit my wife uncle who’s cancer and is not doing to good. Tried to take
> the car but she wanted to go in the RV. So will be heading out in coupler
> days. I have done a few things on the RV but it really needs more tender
> loving care than it got this year. Next year I know I will be making my
> every other trip to up state NY. That one I look forward to as we stay
> next to lake and my wife favorite eating place. This time we will be going
> to another high school graduation.
>
> I started to grease the RV and could not get my grease gun to work.
> Everything is normal for me when I decided to pull out the RV. Last year
> it was a bad alternator that quit the day before I was getting ready to
> leave. A week earlier it was fine when I took the RV for a ride to check
> it out.
>
> Art
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Fan? [message #325984 is a reply to message #325981] Mon, 13 November 2017 23:15 Go to previous messageGo to next message
amansfield1104 is currently offline  amansfield1104   United States
Messages: 80
Registered: August 2009
Karma: 0
Member
Yes it sounds like it needs a new fan motor. I will cut the wire and tape it so it does not short. I might be good for other things.

Art
> On Nov 13, 2017, at 7:26 PM, Ken Henderson wrote:
>
> Art,
>
> Quite aside from the question of whether you need a new blower motor,
> there's the fact that the fan always runs when the key is on. That's a
> design feature intended to keep the cockpit ventilated. Most of us figure
> that after 40 years, the cockpit will ALWAYS be ventilated. So, many of us
> make very simple modification that defeats the always-running blower: At
> the left (driver's) side of the HVAC box under the hood, near the firewall
> and the bottom of the box, there's a multi-wire connector which feeds the
> blower speed resistor pack onto which it's plugged. One of the wires into
> that connector is Yellow. If you do ONE of the following 3 tricks, you'll
> defeat the run-with-ignition feature, leaving all other functions of the
> blower switch unchanged: 1. Cut the yellow wire, 2. Remove that wire
> from the connector, or 3. Unplug the connector, bend that pin over on the
> mating male connector, then re-attach the removed connector. In simpler
> words, disconnect that yellow wire.
>
> ​For some later modification, that disconnected yellow wire may prove
> useful, since it's always "hot" when the ignition is "On".​
>
> Ken H.
>
>
> On Mon, Nov 13, 2017 at 7:57 PM, 1104agm wrote:
>
>> I have 76 and the fan runs when ever the key is on. It sounds like the
>> fan has gone bad. I would like to unhook the wire that connected to the
>> fan when they is on. If I remember I need to disconnect the red wire but
>> it has been a long time since I read how to disconnect the fan when the key
>> is on. I was charging the battery and turned the key on and was surprise
>> that the voltage was so low. Charger was set to 10 amps and the fan was
>> dropping the voltage about 1.5 volts. So that is way to high so the fan
>> needs to go. I need to rebuild the heater and the AC system if I am going
>> to use the RV much. Looks like a lot of work.
>>
>> Had not planned to use the RV this year and now we are heading out to
>> visit my wife uncle who’s cancer and is not doing to good. Tried to take
>> the car but she wanted to go in the RV. So will be heading out in coupler
>> days. I have done a few things on the RV but it really needs more tender
>> loving care than it got this year. Next year I know I will be making my
>> every other trip to up state NY. That one I look forward to as we stay
>> next to lake and my wife favorite eating place. This time we will be going
>> to another high school graduation.
>>
>> I started to grease the RV and could not get my grease gun to work.
>> Everything is normal for me when I decided to pull out the RV. Last year
>> it was a bad alternator that quit the day before I was getting ready to
>> leave. A week earlier it was fine when I took the RV for a ride to check
>> it out.
>>
>> Art
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> _______________________________________________
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> Unsubscribe or Change List Options:
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Re: [GMCnet] Fan? [message #325985 is a reply to message #325978] Tue, 14 November 2017 00:00 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
Just unplug the wire from the connector. I reused that wire to power my added vacuum pump for the brakes. If you cut it and later you decide you want to use it, you will have to put some kind if connector back on it. So why not just leave the connector on it and tape it up.

On the noisy motor, Only 4 screws and one wire connection hold it in. Itis a 10 minute job to replace it. The last one I replaced was in an Autozone parking lot in Fallon, NV. Autozone had the new one in stock. 10 or 15 minutes and I was on my way.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Fan? [message #325986 is a reply to message #325985] Tue, 14 November 2017 00:46 Go to previous messageGo to next message
powerjon is currently offline  powerjon   United States
Messages: 2446
Registered: January 2004
Karma: 5
Senior Member
The fan motor is a part# PM102 at you're friendly AutoZone Parts store. Just a little under $20. You will have to R&R the squire cage between the two motor. After that it is a 10 minute job like Ken says. Don’t cut any wires!

JR Wright
> On Nov 14, 2017, at 1:01 AM, Ken Burton wrote:
>
> Just unplug the wire from the connector. I reused that wire to power my added vacuum pump for the brakes. If you cut it and later you decide you
> want to use it, you will have to put some kind if connector back on it. So why not just leave the connector on it and tape it up.
>
> On the noisy motor, Only 4 screws and one wire connection hold it in. Itis a 10 minute job to replace it. The last one I replaced was in an Autozone
> parking lot in Fallon, NV. Autozone had the new one in stock. 10 or 15 minutes and I was on my way.
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
>
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J.R. Wright
GMC GreatLaker
GMC Eastern States
GMCMI
78 30' Buskirk Stretch
75 Avion Under Reconstruction
Michigan
Re: [GMCnet] Fan? [message #325987 is a reply to message #325986] Tue, 14 November 2017 01:32 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
Messages: 7117
Registered: August 2005
Karma: 2
Senior Member
On Mon, Nov 13, 2017 at 10:47 PM John Wright wrote:

> The fan motor is a part# PM102 at you're friendly AutoZone Parts store.
> Just a little under $20. You will have to R&R the squire cage between the
> two motor. After that it is a 10 minute job like Ken says. Don’t cut any
> wires!
>

Like they say
Read here
http://www.gmcmhphotos.com/photos/vacuum-pumps-new-models/p24284-jc4-pump1.html
And the next few slides show you where and why to get the power


> JR Wright
>> On Nov 14, 2017, at 1:01 AM, Ken Burton wrote:
>>
>> Just unplug the wire from the connector. I reused that wire to power my
> added vacuum pump for the brakes. If you cut it and later you decide you
>> want to use it, you will have to put some kind if connector back on it.
> So why not just leave the connector on it and tape it up.
>>
>> On the noisy motor, Only 4 screws and one wire connection hold it in.
> Itis a 10 minute job to replace it. The last one I replaced was in an
> Autozone
>> parking lot in Fallon, NV. Autozone had the new one in stock. 10 or
> 15 minutes and I was on my way.
>> --
>> 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
>
>
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--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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Re: [GMCnet] Fan? [message #325990 is a reply to message #325987] Tue, 14 November 2017 06:48 Go to previous message
tphipps is currently offline  tphipps   United States
Messages: 3005
Registered: August 2004
Location: Spanish Fort, AL
Karma: 9
Senior Member
I used the 'yellow wire' to pull in a 12v relay, putting a heavy gauge wire, directly from the house battery, to a fuse panel. This panel is hot when the engine is running. Used the fuse panel to power my JC4 and Ken's wonderful wipers.
Tom, MS II GMCless


2012 Phoenix Cruiser model 2552 KA4CSG
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