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Rear suspension raising issue [message #348203] Fri, 20 September 2019 20:04 Go to next message
dpottebaum is currently offline  dpottebaum   United States
Messages: 100
Registered: January 2013
Location: Bondurant, Iowa
Karma: 0
Senior Member
Hello, I've got a 1978 Royale with the electro level 1 system. When I'm trying to level at a campsite neither side will raise. They will both lower. The compressor fires up to get the tank pressure to 120 pounds at vehicle start up, but nothing actually happens when I try to inflate the bags. I am unsure if the system is working in Travel mode while going down the road. I have tried both Travel and Hold while at the campsite with no success. Is it possible that both raise solenoids failed at the same time? Seems unusual for that to happen as well as having both switches fail or both circuits lose continuity (although I have not checked for that). The 30 AMP fuse at the glove box is also fine. I have not bench tested the solenoids. I'm sure I'm missing something obvious. Thanks for any insights.

Dave Pottebaum Bondurant, Iowa 1978 Royale
Re: [GMCnet] Rear suspension raising issue [message #348237 is a reply to message #348203] Sat, 21 September 2019 08:34 Go to previous messageGo to next message
dsmithy is currently offline  dsmithy   United States
Messages: 210
Registered: July 2012
Location: Lincoln Nebraska
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Senior Member
Dave,
I’ve got the same “problem.” The issue is that if the whole system has more pressure than your pump relay wants to start the pump, it’s not gonna go. I just drop the pressure in a bag and then raise it enough to activate the pump, then it raises everything till it shuts off at the high pressure cutoff. Wiser people will correct me here, but I don’t think either of us has a problem.
Doug


Douglas & Virginia Smith
dsmithy18 at gmail
Lincoln Nebraska
’73 “Canyonlands” since ‘95: “Wanabizo”, Anishinabe Indian for “He gets lost driving” Yes, really.
Quadrabag/6 wheel disks/3;70 final/Paterson QuadraJet/Thorley’s/Sundry other
P&W PT6, no wait, that's the wish list...

> On Sep 20, 2019, at 8:04 PM, Dave Pottebaum via Gmclist wrote:
>
> Hello, I've got a 1978 Royale with the electro level 1 system. When I'm trying to level at a campsite neither side will raise. They will both lower.
> The compressor fires up to get the tank pressure to 120 pounds at vehicle start up, but nothing actually happens when I try to inflate the bags. I
> am unsure if the system is working in Travel mode while going down the road. I have tried both Travel and Hold while at the campsite with no success.
> Is it possible that both raise solenoids failed at the same time? Seems unusual for that to happen as well as having both switches fail or both
> circuits lose continuity (although I have not checked for that). The 30 AMP fuse at the glove box is also fine. I have not bench tested the
> solenoids. I'm sure I'm missing something obvious. Thanks for any insights.
> --
> Dave Pottebaum
> Bondurant, Iowa
> 1978 Royale
>
> _______________________________________________
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> Unsubscribe or Change List Options:
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Douglas & Virginia Smith, dsmithy18 at gmail, Lincoln Nebraska, ’73 “Sequoia” since ‘95: "Wanabizo"; Quadrabag/6 wheel disks/3:70 final/Paterson QuadraJet/Thorley’s/Alloy wheels/Sundry other
Re: [GMCnet] Rear suspension raising issue [message #348243 is a reply to message #348203] Sat, 21 September 2019 09:19 Go to previous messageGo to next message
dsmithy is currently offline  dsmithy   United States
Messages: 210
Registered: July 2012
Location: Lincoln Nebraska
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Senior Member
Sorry Dave, I just gave you a non-solution. The electro-level guys should weigh in here.
Doug


Douglas & Virginia Smith
dsmithy18 at gmail
Lincoln Nebraska
’73 “Canyonlands” since ‘95: “Wanabizo”, Anishinabe Indian for “He gets lost driving” Yes, really.
Quadrabag/6 wheel disks/3;70 final/Paterson QuadraJet/Thorley’s/Sundry other
P&W PT6, no wait, that's the wish list...

> On Sep 20, 2019, at 8:04 PM, Dave Pottebaum via Gmclist wrote:
>
> Hello, I've got a 1978 Royale with the electro level 1 system. When I'm trying to level at a campsite neither side will raise. They will both lower.
> The compressor fires up to get the tank pressure to 120 pounds at vehicle start up, but nothing actually happens when I try to inflate the bags. I
> am unsure if the system is working in Travel mode while going down the road. I have tried both Travel and Hold while at the campsite with no success.
> Is it possible that both raise solenoids failed at the same time? Seems unusual for that to happen as well as having both switches fail or both
> circuits lose continuity (although I have not checked for that). The 30 AMP fuse at the glove box is also fine. I have not bench tested the
> solenoids. I'm sure I'm missing something obvious. Thanks for any insights.
> --
> Dave Pottebaum
> Bondurant, Iowa
> 1978 Royale
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org


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Douglas & Virginia Smith, dsmithy18 at gmail, Lincoln Nebraska, ’73 “Sequoia” since ‘95: "Wanabizo"; Quadrabag/6 wheel disks/3:70 final/Paterson QuadraJet/Thorley’s/Alloy wheels/Sundry other
Re: [GMCnet] Rear suspension raising issue [message #348354 is a reply to message #348237] Sun, 22 September 2019 07:26 Go to previous messageGo to next message
dpottebaum is currently offline  dpottebaum   United States
Messages: 100
Registered: January 2013
Location: Bondurant, Iowa
Karma: 0
Senior Member
Thanks Doug. I'll keep trying things today. I see the William Schurman started a new thread with a similar problem except his is isolated to one side. My son is home today so we'll tag team on this and keep tracing the problem back.

Dave Pottebaum Bondurant, Iowa 1978 Royale
Re: [GMCnet] Rear suspension raising issue [message #348710 is a reply to message #348354] Sun, 29 September 2019 21:45 Go to previous messageGo to next message
dpottebaum is currently offline  dpottebaum   United States
Messages: 100
Registered: January 2013
Location: Bondurant, Iowa
Karma: 0
Senior Member
While I'm replacing a couple 2 way solenoids, I am also going to replace the pressure switch. It had a P61NA-10 Johnson Controls switch in it. I have not had much luck finding an equivalent. Anyone have some suggestions for a good replacement? Thanks.

Dave Pottebaum Bondurant, Iowa 1978 Royale
Re: [GMCnet] Rear suspension raising issue [message #348712 is a reply to message #348710] Sun, 29 September 2019 22:00 Go to previous messageGo to next message
Emery Stora is currently offline  Emery Stora   United States
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Registered: January 2011
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The GMC originally came with a shallow well pressure switch. Check Amazon under that description. There are many.
Here is one that should probably work but check the pressure on and pressure setting ability.

https://www.amazon.com/Square-Schneider-Electric-FSG2J24CP-Pumptrol/dp/B000BQSERE/ref=sr_1_9?crid=1QMWLTQTECNNU&keywords=shallow+well+pressure+swi tch&qid=1569811976&s=gateway&sprefix=shallow+well+pressure%2Caps%2C173&sr=8-9

Emery Stora
77 Kingsley
Frederick, CO

> On Sep 29, 2019, at 8:45 PM, Dave Pottebaum via Gmclist wrote:
>
> While I'm replacing a couple 2 way solenoids, I am also going to replace the pressure switch. It had a P61NA-10 Johnson Controls switch in it. I
> have not had much luck finding an equivalent. Anyone have some suggestions for a good replacement? Thanks.
> --
> Dave Pottebaum
> Bondurant, Iowa
> 1978 Royale

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Re: [GMCnet] Rear suspension raising issue [message #348715 is a reply to message #348712] Sun, 29 September 2019 22:45 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 stock two kind, one has a unloader option gmcrvparts.com

On Sun, Sep 29, 2019 at 8:00 PM Emery Stora via Gmclist <
gmclist@list.gmcnet.org> wrote:

> The GMC originally came with a shallow well pressure switch. Check Amazon
> under that description. There are many.
> Here is one that should probably work but check the pressure on and
> pressure setting ability.
>
>
> https://www.amazon.com/Square-Schneider-Electric-FSG2J24CP-Pumptrol/dp/B000BQSERE/ref=sr_1_9?crid=1QMWLTQTECNNU&keywords=shallow+well+pressure+swi tch&qid=1569811976&s=gateway&sprefix=shallow+well+pressure%2Caps%2C173&sr=8-9
> https://www.amazon.com/Square-Schneider-Electric-FSG2J24CP-Pumptrol/dp/B000BQSERE/ref=sr_1_9?crid=1QMWLTQTECNNU&keywords=shallow+well+pressure+swi tch&qid=1569811976&s=gateway&sprefix=shallow+well+pressure,aps,173&sr=8-9
>>
>
> Emery Stora
> 77 Kingsley
> Frederick, CO
>
>> On Sep 29, 2019, at 8:45 PM, Dave Pottebaum via Gmclist gmclist@list.gmcnet.org> wrote:
>>
>> While I'm replacing a couple 2 way solenoids, I am also going to replace
> the pressure switch. It had a P61NA-10 Johnson Controls switch in it. I
>> have not had much luck finding an equivalent. Anyone have some
> suggestions for a good replacement? Thanks.
>> --
>> Dave Pottebaum
>> Bondurant, Iowa
>> 1978 Royale
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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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
Re: [GMCnet] Rear suspension raising issue [message #348718 is a reply to message #348710] Sun, 29 September 2019 23:35 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
Karma: 10
Senior Member
These switches are used on air compressors and fairly common. The problem is there are many different types ans specs. The easiest thing is to order one form Jim K as he has already figured out which one is the correct one. I would get the one with the unloader, even if you do not implement it now it is a simple addition to later to add one Tee and a short piece of hose.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: Rear suspension raising issue [message #348720 is a reply to message #348203] Mon, 30 September 2019 08:15 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Registered: October 2006
Location: Woodstock, IL
Karma: 12
Senior Member
78 with EL1? That's confusing.
My guess is gummed contacts on the switch panel switches. The thin foam dust shield turns to foam goo and gets in the contacts You can unplug the panel and bench test continuity functions on the bench. Then open and service the switches if need be. Very easy on a clean bench, just watch springs and small parts. I had to physically clean the contact points as the little foam balls bonded to contacts
I don't know why you are chasing pressure switch if there is120PSI at tank


John Lebetski
Woodstock, IL
77 Eleganza II
Re: Rear suspension raising issue [message #348721 is a reply to message #348203] Mon, 30 September 2019 08:23 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Registered: October 2006
Location: Woodstock, IL
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Senior Member
If you think about it, the UP contacts are closer to the bottom of the switch where more debris would collect.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: Rear suspension raising issue [message #348745 is a reply to message #348720] Mon, 30 September 2019 18:38 Go to previous messageGo to next message
dpottebaum is currently offline  dpottebaum   United States
Messages: 100
Registered: January 2013
Location: Bondurant, Iowa
Karma: 0
Senior Member
John, thanks for the suggestions. The pressure switch is unrelated to the problem I was asking about. I broke a connection on the switch when I was taking things apart. As for the EL 1, that's what it is. Some 78's had them and others had the EL2. Apparently, it was a transition year similar to the 455 to 403 the year before.

Dave Pottebaum Bondurant, Iowa 1978 Royale
Re: [GMCnet] Rear suspension raising issue [message #348746 is a reply to message #348718] Mon, 30 September 2019 18:53 Go to previous message
dpottebaum is currently offline  dpottebaum   United States
Messages: 100
Registered: January 2013
Location: Bondurant, Iowa
Karma: 0
Senior Member
I just ordered the switch with the unloader from Jim. Thanks for the suggestion, Ken.

Dave Pottebaum Bondurant, Iowa 1978 Royale
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