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Taking care of issues [message #202271] Wed, 20 March 2013 14:02 Go to next message
Richard Andis is currently offline  Richard Andis   United States
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Registered: January 2013
Location: HELL Paso, TX
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I picked up my 78 Royale rear twin from Bryan Wheat last Friday. Finally getting around to some issues before heading out on a 2000+ mile journey in early April.

Currently they are;

Oil Pressure gauge is pegged to "H", doesn't back off after a reasonable time

Low Engine Coolant light on constantly

Remote start for 6000KW Onan not working

Below is what I have done so far. Let me know if I'm doing anything wrong or if here's something else I can do.

Oil pressure switch - I removed the wire, gauge remained on "H". Grounded wire, gauge went to "L". I suspect bad sender. Is this a component that I can get locally? Or do I have to order from Applied or Coop?

Low Engine Coolant - PO stated that it possibly had a bad radiator probe. Waterpump had been recently changed. First I check the coolant level. Overflow was empty. Filled radiator and overflow tank with coolant. While checking the location of the probe I discovered yellow wire to probe disconnected. Reconnected wire. Started up engine and let it run for around 5 minutes. Low Engine Coolant light remained on. Reviewed troubleshooting procedure in shop manual and it instructs you to disconnect probe wire and the Low Engine Coolant light should go out (it didn't). It then directs you to replace the Low Coolant Switching module. Should I go ahead and replace or wait a couple of uses before replacement

Remote Generator Start - Generator will neither start or stop from the remote panel by the galley. I haven't opened up the panel yet but I suspect it's just the switch. I'll try bypassing the remote switch with jumper (Switch Pin 1 to 3 for start, Switch Pin 1 to 2 for stop). Any other ideas would be helpful.





Valhalla - 1978 GMC Royale rear twin [SOLD]
Walküre - 1974 VW Thing (Toad)

[Updated on: Wed, 20 March 2013 14:04]

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Re: Taking care of issues [message #202275 is a reply to message #202271] Wed, 20 March 2013 14:43 Go to previous messageGo to next message
John Heslinga   Canada
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Registered: February 2011
Location: Edmonton, Alberta, Canada
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Hi Richard:

Re onan remote start: A very common problem is the 4 pin connector behind the generator that your remote wires connect to. It gets corroded and causes problems like you describe. You can take it apart and service it or replace the connector itself with a 4 way trailer plug. Some have just permanently connected the wires.

Re oil sender: it's a common part. You'll have to get the cross over from the list. I dont have it handy, Our "Great Suppliers" have them. Support them when ever you can

Re coolant level. Looks like the module is defective if you followed the steps. Make sure you check the sender too. There should be a process identified for it too.





John and Cathie Heslinga 1974 Canyonlands 260 455, Manny tranny and 1 ton, 3:70 LS, Red Seal Journeyman, DTE, BEd. MEd. Edmonton, Alberta
Re: [GMCnet] Taking care of issues [message #202277 is a reply to message #202271] Wed, 20 March 2013 15:31 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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Registered: August 2005
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read here
http://gmcmotorhome.info/generator.html#No
gene


> Remote Generator Start - Generator will neither start or stop from the
> remote panel by the galley. I haven't opened up the panel yet but I suspect
> it's just the switch. I'll try bypassing the remote switch with jumper (Pin
> 1 to 2 for start, Pin 1 to 3 for stop). Any other ideas would be helpful.
>
>
>
>
> --
> "Vahalla" - 1978 GMC Royale
> "Walküre" - 1974 VW Thing
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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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] Taking care of issues [message #202280 is a reply to message #202271] Wed, 20 March 2013 16:01 Go to previous messageGo to next message
powwerjon is currently offline  powwerjon   United States
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See my comments below.

J.R. Wright
30' Buskirk Stretch
Michigan
On Location at Dothan

On Mar 20, 2013, at 2:02 PM, Richard Andis <randisintexas@gmail.com> wrote:

>
>
> I picked up my 78 Royale rear twin from Bryan Wheat last Friday. Finally getting around to some issues before heading out on a 2000+ mile journey in early April.
>
> Currently they are;
>
> Oil Pressure gauge is pegged to "H", doesn't back off after a reasonable time

The oil pressure switch is a common part. A the part numbers that I list here are for a 0-80 psig pressure sender. With the 0-80 sender your at 40 psi at mid scale.
AC/Delco D1813
NAPA numbers OP6636, OP6636SB, OP6638, OP6638SB
Standard part# ps-157
Wells part # ps-136
Buy these locally as shipping will be more than the sender.
>
> Low Engine Coolant light on constantly

You could have a bad board or sender. First you need to make sure that you have all the air out of the cooling system. If the water pump had been change recently then air could still be present. If you have no further drop in coolant level in the overflow tank then you may have all the air out. Be sure that you are using a 9 or 10 pound cap on your radiator. The sender and module is available from Jim K and is fairly priced.
>
> Remote start for 6000KW Onan not working

The remote panel rarely has problems. There is a 4 wire connector back behind the generator that fails with corrosion and can be replace with butt splices or a trailer plug. This is a common problem with our coaches. The wires will come apart in your hands.
>
> Below is what I have done so far. Let me know if I'm doing anything wrong or if here's something else I can do.
>
> Oil pressure switch - I removed the wire, gauge remained on "H". Grounded wire, gauge went to "L". I suspect bad sender. Is this a component that I can get locally? Or do I have to order from Applied or Coop?
>
> Low Engine Coolant - PO stated that it possibly had a bad radiator probe. Waterpump had been recently changed. First I check the coolant level. Overflow was empty. Filled radiator and overflow tank with coolant. While checking the location of the probe I discovered yellow wire to probe disconnected. Reconnected wire. Started up engine and let it run for around 5 minutes. Low Engine Coolant light remained on. Reviewed troubleshooting procedure in shop manual and it instructs you to disconnect probe wire and the Low Engine Coolant light should go out (it didn't). It then directs you to replace the Low Coolant Switching module. Should I go ahead and replace or wait a couple of uses before replacement
>
> Remote Generator Start - Generator will neither start or stop from the remote panel by the galley. I haven't opened up the panel yet but I suspect it's just the switch. I'll try bypassing the remote switch with jumper (Pin 1 to 2 for start, Pin 1 to 3 for stop). Any other ideas would be helpful.
>
>
>
>
> --
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Re: [GMCnet] Taking care of issues [message #202293 is a reply to message #202280] Wed, 20 March 2013 18:51 Go to previous messageGo to next message
Richard Andis is currently offline  Richard Andis   United States
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Registered: January 2013
Location: HELL Paso, TX
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Thanks a lot. Looks like NAPA OP6638 took care of it. Just for the record though, the can on replacement part was a little bit bigger round that the existing one. Ended up being a little tight against some springy thing with a cover. Removing the cover, spinning on the new part, replacing the cover worked fine.


Now, 1 out of three done.

Took a look under the Onan but didn't see any 4 wire connector. I did locate a twelve pin Molex connector (along with some squirrel's winter stash). Looked through the GMC Photo site in order to get some idea what I was looking for. Couldn't find anything.


No change on the Low Coolant light. It's going to get a good workout this weekend though.


Valhalla - 1978 GMC Royale rear twin [SOLD]
Walküre - 1974 VW Thing (Toad)

[Updated on: Wed, 20 March 2013 20:27]

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Re: [GMCnet] Taking care of issues [message #202363 is a reply to message #202293] Thu, 21 March 2013 10:13 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Location: Hebron, Indiana
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To get to that Onan connector, pull the Onan all the way out. Block up the frame of the coach so it can not fall on you if an air bag should leak or blow. Crawl under the coach and look straight up at the frame that holds the Onan. You are looking for a cable with a flat connector. It is located near the rear inside corner of the mounting frame.

The Oil pressure sender is available from Advanced. Just make sure you get a sender for a gauge and not a sender for an oil pressure light. Tell them 1975 Olds Toronado. AutoZone did not have it in stock when I needed it, and I did not check NAPA.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Taking care of issues [message #202364 is a reply to message #202363] Thu, 21 March 2013 10:22 Go to previous messageGo to next message
Richard Andis is currently offline  Richard Andis   United States
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Ken Burton wrote on Thu, 21 March 2013 10:13

To get to that Onan connector, pull the Onan all the way out. Block up the frame of the coach so it can not fall on you if an air bag should leak or blow. Crawl under the coach and look straight up at the frame that holds the Onan. You are looking for a cable with a flat connector. It is located near the rear inside corner of the mounting frame.

The Oil pressure sender is available from Advanced. Just make sure you get a sender for a gauge and not a sender for an oil pressure light. Tell them 1975 Olds Toronado. AutoZone did not have it in stock when I needed it, and I did not check NAPA.


Thanks, I've taken care of the oil sender unit. Going to crawl under the coach later today in search of that connector. What effect does a blown fuse on the control panel have. The generator starts fine locally, just not remotely.



Valhalla - 1978 GMC Royale rear twin [SOLD]
Walküre - 1974 VW Thing (Toad)
Re: [GMCnet] Taking care of issues [message #202367 is a reply to message #202364] Thu, 21 March 2013 10:27 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Nothing will work with that fuse on the Onan control board blown. I believe it is 5 amp. Do not go oversize because it will blow patterns on the board instead of the fuse.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Taking care of issues [message #202384 is a reply to message #202367] Thu, 21 March 2013 12:51 Go to previous messageGo to next message
Richard Andis is currently offline  Richard Andis   United States
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Registered: January 2013
Location: HELL Paso, TX
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Ken Burton wrote on Thu, 21 March 2013 10:27

Nothing will work with that fuse on the Onan control board blown. I believe it is 5 amp. Do not go oversize because it will blow patterns on the board instead of the fuse.


Thanks, I'll take another look tomorrow for that elusive connector. Today she's getting new windshields and tinting.


Valhalla - 1978 GMC Royale rear twin [SOLD]
Walküre - 1974 VW Thing (Toad)
Re: Taking care of issues [message #202392 is a reply to message #202271] Thu, 21 March 2013 14:10 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Richard Andis wrote on Wed, 20 March 2013 15:02

I picked up my 78 Royale rear twin from Bryan Wheat last Friday. Finally getting around to some issues before heading out on a 2000+ mile journey in early April.
<snip>

Richard,

Welcome to the group, family, cult, asylum.....

What you propose can be done. Yours Truly and several others have done similar. If you are ready for it, the excursion will be memorable.

Now that you are an owner and you have identified what the community can do for you, I have something else. You will soon discover that these coaches are not just another toy that you own. They quickly become much more a part of your life than that. As I am a waterman, I liken it to the relation that we have with our boats and this brought me to thinking that there should be a similar greeting for new owners. That is why I like to welcome new owners with;

May the Good Lord bless this coach and all those that set forth within her.

Welcome Richard

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: Taking care of issues [message #202396 is a reply to message #202392] Thu, 21 March 2013 15:00 Go to previous message
Richard Andis is currently offline  Richard Andis   United States
Messages: 261
Registered: January 2013
Location: HELL Paso, TX
Karma: 0
Senior Member
Matt Colie wrote on Thu, 21 March 2013 14:10


Welcome to the group, family, cult, asylum.....

Welcome Richard

Matt


Thanks for the welcome. One of the reasons for selecting the GMC is that I like to do my own work and customize things to my own taste. My other obsession in air-cooled VWs which I spend a great deal of time with. My other vehicle is a 1974 VW Thing so a 1978 GMC is a modernization upgrade of sorts.


Valhalla - 1978 GMC Royale rear twin [SOLD]
Walküre - 1974 VW Thing (Toad)

[Updated on: Thu, 21 March 2013 15:00]

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