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1978 GMC Royale [message #146935] Tue, 18 October 2011 15:04 Go to next message
tillie1001 is currently offline  tillie1001   United States
Messages: 33
Registered: October 2011
Location: Michigan
Karma: 0
Member

Hi Everyone,

I just purchased ,a few weeks ago, my very own GMC 1978 Royale. I love her. I have owned two other motorhomes previously, but not a GMC, so although I get the idea of how most of it works, I am lost on a few other things. I cannot seem to find any information on the "Royale" itself, alot on other 78 gmc's but not the Royale. I contacted Cinnabar here in Michigan, they are approx 2 hours from me. I want to take it to them for a complete run thru, problem is, the rear air system is low, and I dont want to add air into the system incorrectly. I have one toggle switch inside with a gauge next to it, reading 80, all the info I am finding on the air system say they have three or more toggles... then when i pressed the toggle a bit of smoke came out and well that scared me. I see there is a manual way of adding air next to the bag itself, I just dont want to over inflate. It does not seem to be losing air, but it just doesn't seem to be quite high enough. Does anyone have any suggestions out there for me. Thanks for your time!
Re: 1978 GMC Royale [message #146936 is a reply to message #146935] Tue, 18 October 2011 15:07 Go to previous messageGo to next message
C Boyd is currently offline  C Boyd   United States
Messages: 2629
Registered: April 2006
Karma: 18
Senior Member
tillie1001 wrote on Tue, 18 October 2011 16:04

Hi Everyone,

I just purchased ,a few weeks ago, my very own GMC 1978 Royale. I love her. I have owned two other motorhomes previously, but not a GMC, so although I get the idea of how most of it works, I am lost on a few other things. I cannot seem to find any information on the "Royale" itself, alot on other 78 gmc's but not the Royale. I contacted Cinnabar here in Michigan, they are approx 2 hours from me. I want to take it to them for a complete run thru, problem is, the rear air system is low, and I dont want to add air into the system incorrectly. I have one toggle switch inside with a gauge next to it, reading 80, all the info I am finding on the air system say they have three or more toggles... then when i pressed the toggle a bit of smoke came out and well that scared me. I see there is a manual way of adding air next to the bag itself, I just dont want to over inflate. It does not seem to be losing air, but it just doesn't seem to be quite high enough. Does anyone have any suggestions out there for me. Thanks for your time!



C. Boyd
76 Crestmont
East Tennessee
Re: 1978 GMC Royale [message #146939 is a reply to message #146935] Tue, 18 October 2011 16:04 Go to previous messageGo to next message
RickOH is currently offline  RickOH   United States
Messages: 29
Registered: December 2006
Location: Coshocton OH
Karma: 0
Junior Member
I run my 78 Royale at 90 lbs . If you have a manual shrader valve next to the air bag with a shut-off valve to isolate that bag from the rest of the system, thats probably what they have been doing. Mine is set up that way and the on-board compressor is disconnected. Been using it that way for four yrs with no problem just need to add air about every 3 mos.


Rick Little
Coshocton OH
78 Royale
Re: 1978 GMC Royale [message #146943 is a reply to message #146939] Tue, 18 October 2011 16:30 Go to previous messageGo to next message
tillie1001 is currently offline  tillie1001   United States
Messages: 33
Registered: October 2011
Location: Michigan
Karma: 0
Member

Yes it does have the schrader and shut off, thanks. I bought her from an estate, the owner had passed and the executer of the estate sold it to me, and unfortunatly he did not know much about the unit. Thanks so much for your help
Re: [GMCnet] 1978 GMC Royale [message #146946 is a reply to message #146939] Tue, 18 October 2011 16:36 Go to previous messageGo to next message
Byron Songer is currently offline  Byron Songer   United States
Messages: 1912
Registered: August 2007
Location: Louisville, KY
Karma: -2
Senior Member

The amount of pressure in the bags is a variable thing. It's going to depend
on the weight of the coach and the height at which you want it setting for
optimum control. Another "depends" will be how the torsion bars are adjusted
as to whether more resulting weight is on one side from the other.

I had valves put on the air bags of our rear bath Royale. I set the rear
ride height like a lot of us have done. Cut a stick about a foot long and
two inches out of a piece of 3/4-inch plywood. Notch it at the right height.
Fill the bags so that the frame is the proper height from the ground (or you
can measure from the holes in the frame). The rear ride height is 11 11/16
+- 1/4 from the top of the rear slots to level ground. The slots are on the
frame under the rear hatches. It'll be difficult to find the one under the
generator compartment but it won't be impossible. Once the ride height is
set correctly you can mark you stick (or cut a notch) based on ground to
lower edge of the frame at the point you desire.

Note that the front ride height is greater than the rear. In other words, at
regular traveling position, the GMC tends to squat a bit.

Have you looked on http://www.bdub.net/manuals/index.html for manuals
relating to the 78 GMC and the Coachmen 1978 manual?

--

Byron Songer
Louisville, KY
http://www.gmceast.com

Sights to see and places to stay ­
Find or submit a
GMCer recommendation
http://www.gmceast.com/travel



rick little wrote:

>
>
> I run my 78 Royale at 90 lbs . If you have a manual shrader valve next to the
> air bag with a shut-off valve to isolate that bag from the rest of the system,
> thats probably what they have been doing. Mine is set up that way and the
> on-board compressor is disconnected. Been using it that way for four yrs with
> no problem just need to add air about every 3 mos.
>
>
> Rick Little
> Coshocton OH
> 78 Royale
> _______________________________________________
> GMCnet mailing list
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-- Byron Songer
Full-timing to enjoy the USA
Former owner but still an admirer
GMC paint schemes at -
http://www.songerconsulting.net
Re: [GMCnet] 1978 GMC Royale [message #146947 is a reply to message #146935] Tue, 18 October 2011 16:38 Go to previous messageGo to next message
Byron Songer is currently offline  Byron Songer   United States
Messages: 1912
Registered: August 2007
Location: Louisville, KY
Karma: -2
Senior Member

Mandie,

One of the things we GMCers (and used to be's) appreciate is using you name,
GMC model, and location in your signature. It helps us learn about you so we
can better recommend who might be someone to be of assistance in your area.
(We'll also know who not to recommend.)


--

Byron Songer
Louisville, KY
http://www.gmceast.com

Sights to see and places to stay ­
Find or submit a GMCer recommendation
http://www.gmceast.com/travel



Mandie wrote:

>
>
> Hi Everyone,
>
> I just purchased ,a few weeks ago, my very own GMC 1978 Royale. I love her. I
> have owned two other motorhomes previously, but not a GMC, so although I get
> the idea of how most of it works, I am lost on a few other things. I cannot
> seem to find any information on the "Royale" itself, alot on other 78 gmc's
> but not the Royale. I contacted Cinnabar here in Michigan, they are approx 2
> hours from me. I want to take it to them for a complete run thru, problem is,
> the rear air system is low, and I dont want to add air into the system
> incorrectly. I have one toggle switch inside with a gauge next to it, reading
> 80, all the info I am finding on the air system say they have three or more
> toggles... then when i pressed the toggle a bit of smoke came out and well
> that scared me. I see there is a manual way of adding air next to the bag
> itself, I just dont want to over inflate. It does not seem to be losing air,
> but it just doesn't seem to be quite high enough. Does anyone have any sugges
> tions out there for me. Thanks for your time!
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist


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-- Byron Songer
Full-timing to enjoy the USA
Former owner but still an admirer
GMC paint schemes at -
http://www.songerconsulting.net
Re: 1978 GMC Royale [message #146948 is a reply to message #146943] Tue, 18 October 2011 16:40 Go to previous messageGo to next message
1275gtsport is currently offline  1275gtsport   Canada
Messages: 272
Registered: September 2009
Location: Rothesay NB
Karma: 0
Senior Member
Welcome aboard Mandie if you do not have the operators manual you can get one here. http://www.bdub.net/manuals/ops78/X7821A.pdf

there is also many other good links on budb's site. http://www.bdub.net/

one thing to know is that these gmc's are meant to ride low in the rear. see page 109 of the linked 1978 manual. I too have only owned one of these great machines for a short time. (just bought our 1977 palm beach in July) but have found that even having the rear up an inch from the manual setting makes a difference in the handling.



Adam Raeburn
Rothesay, NB
1976 Austin Mini
1977 GMC Palm Beach
---------------------------------------------------
Once you replace everything that is attached to something else. It will all be fixed.
Re: 1978 GMC Royale [message #146956 is a reply to message #146935] Tue, 18 October 2011 18:27 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
Messages: 4508
Registered: April 2011
Karma: 39
Senior Member
tillie1001 wrote on Tue, 18 October 2011 15:04

Hi Everyone,

I just purchased ,a few weeks ago, my very own GMC 1978 Royale. I love her. I have owned two other motorhomes previously, but not a GMC, so although I get the idea of how most of it works, I am lost on a few other things. I cannot seem to find any information on the "Royale" itself, alot on other 78 gmc's but not the Royale. I contacted Cinnabar here in Michigan, they are approx 2 hours from me. I want to take it to them for a complete run thru, problem is, the rear air system is low, and I dont want to add air into the system incorrectly. I have one toggle switch inside with a gauge next to it, reading 80, all the info I am finding on the air system say they have three or more toggles... then when i pressed the toggle a bit of smoke came out and well that scared me. I see there is a manual way of adding air next to the bag itself, I just dont want to over inflate. It does not seem to be losing air, but it just doesn't seem to be quite high enough. Does anyone have any suggestions out there for me. Thanks for your time!
If you have enough spare change that you can afford to take it to Cinnabar, how about adopting me and my GMC?
Re: 1978 GMC Royale [message #146959 is a reply to message #146935] Tue, 18 October 2011 18:41 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma: 7
Senior Member
tillie1001 wrote on Tue, 18 October 2011 16:04

Hi Everyone,

I just purchased ,a few weeks ago, my very own GMC 1978 Royale. I love her. I have owned two other motorhomes previously, but not a GMC, so although I get the idea of how most of it works, I am lost on a few other things. I cannot seem to find any information on the "Royale" itself, alot on other 78 gmc's but not the Royale. I contacted Cinnabar here in Michigan, they are approx 2 hours from me. I want to take it to them for a complete run thru, problem is, the rear air system is low, and I dont want to add air into the system incorrectly. I have one toggle switch inside with a gauge next to it, reading 80, all the info I am finding on the air system say they have three or more toggles... then when i pressed the toggle a bit of smoke came out and well that scared me. I see there is a manual way of adding air next to the bag itself, I just dont want to over inflate. It does not seem to be losing air, but it just doesn't seem to be quite high enough. Does anyone have any suggestions out there for me. Thanks for your time!


Mandie,

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

Well, you found the forum, that is one real good start.

Where in Michigan are you?
You have lots of company here and you can probably get someone very familiar with the coach over to you just by asking. (We're funny that way.) I am near Detroit Metro Airport. If I am in striking range to be of assistance, it would be my pleasure to do so. If you would like a lady to come by and give you driving tips, that would be my wife. If it is daylight, she drives the coach. If you need an answer faster than the forum, get to me at seven34- seven53- five 0 five 4.

Did you know about the registry?
We have a guy that is trying to keep track of the remaining GMCs. If you go to the site called <gmcers.org> it will lead you to a set of links. One of those is Bdud's GMC links. Bookmark that one. It will lead you to 96.23% of everything you need to know about the coach.

Is the coach currently winterized?
If it says in Michigan, that is best attended to very soon. The failure to do so may cost you damage to expensive parts.

Cinnabar can be a very effective supplier, but they are one of the most expensive supplier of the five effective and three good.

And lastly, if you live with this coach any time at all, you will find that it is not just something you own - it will be come more than that. I am a waterman, and I liken it to the relationship between a watermen and his boat. So, I greet new owners with this version of out traditional greeting;

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

Welcome Mandie

Matt & Mary Colie


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: 1978 GMC Royale [message #146960 is a reply to message #146935] Tue, 18 October 2011 18:45 Go to previous messageGo to next message
Don A is currently offline  Don A   United States
Messages: 895
Registered: October 2008
Location: Dallas, TX
Karma: 0
Senior Member

Welcome!!

Suggest you check the Black List for owners near you. Should be someone very near you that could come take a look and answer your first questions. And suggest best places to go for work needed.

http://www.bdub.net/Black_List/GMCAssist.pdf


Don Adams Dallas, TX
'76 26' Glenbrook, '90 Sidekick
rebuilt by R Archer, powered by J Bounds, Koba
[IMG]http://www.gmcmhphotos.com/photos/data/6109/G2.jpg[/IMG]
Re: [GMCnet] 1978 GMC Royale [message #146964 is a reply to message #146935] Tue, 18 October 2011 19:25 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
Mandie,

Royale's were outfitted by a company called Coachman. That means a GMC (called a Transmode) with an empty interior was delivered to
Coachman and they installed the interior.

Here's the link to the Coachman Operators manual.

http://www.bdub.net/manuals/coachmen_owners_manual-1978.pdf

Here's a link to another Coachman manual that may be of help to you.

http://www.bdub.net/manuals/Coachmen_1977_26RB_Electrical_-_Plumbing_Drawings.pdf

Regards,
Rob M.

-----Original Message-----
From: Mandie

Hi Everyone,

I just purchased ,a few weeks ago, my very own GMC 1978 Royale. I love her. I have owned two other motorhomes previously, but not a
GMC, so although I get the idea of how most of it works, I am lost on a few other things. I cannot seem to find any information on
the "Royale" itself, alot on other 78 gmc's but not the Royale. I contacted Cinnabar here in Michigan, they are approx 2 hours from
me. I want to take it to them for a complete run thru, problem is, the rear air system is low, and I dont want to add air into the
system incorrectly. I have one toggle switch inside with a gauge next to it, reading 80, all the info I am finding on the air system
say they have three or more toggles... then when i pressed the toggle a bit of smoke came out and well that scared me. I see there
is a manual way of adding air next to the bag itself, I just dont want to over inflate. It does not seem to be losing air, but it
just doesn't seem to be quite high enough. Does anyone have any suggestions out there for me. Thanks for your time!

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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: 1978 GMC Royale [message #146981 is a reply to message #146935] Tue, 18 October 2011 20:50 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
Senior Member
I guess the first question I have since it is a 78 (a good thing) is it Electro Level I or Electro Level II? Simple way to tell is if you have one Vtwin compressor and set of valves it's ELI. 2 compressors ELII. Once you know that you can look at the appropriate diagrams.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: 1978 GMC Royale [message #146986 is a reply to message #146935] Tue, 18 October 2011 21:00 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
Messages: 7111
Registered: November 2004
Location: Dexter, Mo.
Karma: 207
Senior Member
Welcome to our group. You are among some of the best living in Michigan. We have lots of great guys close to the Detroit area and scattered around the state. As Matt said, let us know just where in the state you might be located. Folks get together up there and the Greatlakers are in your area.
Dan


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: [GMCnet] 1978 GMC Royale [message #146987 is a reply to message #146946] Tue, 18 October 2011 21:03 Go to previous messageGo to next message
tillie1001 is currently offline  tillie1001   United States
Messages: 33
Registered: October 2011
Location: Michigan
Karma: 0
Member

I did look up manuals on bdubs, but I am finding only for the 78 in general not specifically the coachman, and printed that out to bb to at least have a basis. However, I may not have searched hard enough, so I am going back to the site to search again. And in the morning I am building a stick... Smile great advice. Thanks
Re: [GMCnet] 1978 GMC Royale [message #146988 is a reply to message #146947] Tue, 18 October 2011 21:09 Go to previous messageGo to next message
tillie1001 is currently offline  tillie1001   United States
Messages: 33
Registered: October 2011
Location: Michigan
Karma: 0
Member

Sorry, I added my info to my signature. Thanks
Re: 1978 GMC Royale [message #146995 is a reply to message #146959] Tue, 18 October 2011 21:34 Go to previous messageGo to next message
tillie1001 is currently offline  tillie1001   United States
Messages: 33
Registered: October 2011
Location: Michigan
Karma: 0
Member

Hi Matt and Mary,

Well I am located in Clarkston, which is about 10 miles north of the Palace of Auburn Hills off I-75. I have owned a 1977 Midas motorhome and a 1984 Holiday Rambler both c class, and what a difference driving this GMC, it is so nice to not drive a shoe box in a wind storm...lol...
The GMC is so nostalgic to me, I remember staring at them in campgrounds when I was a child, yes she is only two years younger than me Smile... and I always wanted one, and I am so pleased with her.

I try to learn before I play, so that is why I am reaching out to this forum. I need to understand her fully before venturing out to far that way if I run into a issue, I am not calling parts on her "thingamajiggy's" lol..

Yes, winterizing her this weekend...
Re: [GMCnet] 1978 GMC Royale [message #146997 is a reply to message #146987] Tue, 18 October 2011 21:39 Go to previous messageGo to next message
C Boyd is currently offline  C Boyd   United States
Messages: 2629
Registered: April 2006
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Senior Member
tillie1001 wrote on Tue, 18 October 2011 22:03

I did look up manuals on bdubs, but I am finding only for the 78 in general not specifically the coachman, and printed that out to bb to at least have a basis. However, I may not have searched hard enough, so I am going back to the site to search again. And in the morning I am building a stick... Smile great advice. Thanks







Here is some differences in pics.
http://www.bdub.net/publications/


C. Boyd
76 Crestmont
East Tennessee
Re: 1978 GMC Royale [message #146999 is a reply to message #146981] Tue, 18 October 2011 21:49 Go to previous messageGo to next message
tillie1001 is currently offline  tillie1001   United States
Messages: 33
Registered: October 2011
Location: Michigan
Karma: 0
Member

Hi,

Since I have never delt with a air ride system before, I dont even know where I would find the compressor (sorry I am such a newbie), I believe I found it in my rear bath, but I am guessing. The pictures I found of the electro systems I and II, showed more buttons (toggles) on the inside of the unit, so I am not sure what is original to the unit and what has been modified, and since so far I have only had my hands on non-coachman manuals the pictures of the compressors in there look different than the "maybe" compressor I am finding in the bathroom...

I now have a link to coachman and I am going there now to see if they have the manual, so hopefully my scavenger hunt will be productive.... Smile Thanks for all the help!

I am still trying to figure out what the green hose is for comming out under my back bumper....LOL..... OH MY!


Mandie Raymond Clarkston, MI 1978 GMC Royale with rear bath
Re: [GMCnet] 1978 GMC Royale [message #147009 is a reply to message #146999] Tue, 18 October 2011 22:44 Go to previous messageGo to next message
Byron Songer is currently offline  Byron Songer   United States
Messages: 1912
Registered: August 2007
Location: Louisville, KY
Karma: -2
Senior Member

Mandie,

The compressors on a rear bath Royale are under the couch/bunk on the driver
side. As you look at the couch they are behind the set of doors on the left
(toward the rear).

It does sound as though a previous owner has modified the original setup.
ElectroLevel I and II had the same buttons in the cockpit -- three. If you
don't have that then you know your coach has been modified. With that said,
there is no telling what you do/don't have.

Are the airbags like the original design with just one on each side? Are the
bags in good shape? No obvious signs of dry rot, cracking or surface damage
from road debris?

If you have a green hose coming out from the back bumper you may have a
macerator -- motor-driven propeller that chews up the sewage from the black
tank.

By the way, you should have a black and gray tank.

One crazy thing about the Coachmen conversions -- though done, somewhat, in
the same way, each one was handled differently. Standards for where things
were located or how they were done was different from construction team to
construction team. The crews that worked on GMC-upfitted coaches followed
more strict standards and procedures. For instance, there may be a
difference as to where your house battery is located vs the chassis
batteries.

--

Byron Songer
Louisville, KY
http://www.gmceast.com

Sights to see and places to stay ­
Find or submit a
GMCer recommendation
http://www.gmceast.com/travel



Mandie wrote:

>
>
> Hi,
>
> Since I have never delt with a air ride system before, I dont even know where
> I would find the compressor (sorry I am such a newbie), I believe I found it
> in my rear bath, but I am guessing. The pictures I found of the electro
> systems I and II, showed more buttons (toggles) on the inside of the unit, so
> I am not sure what is original to the unit and what has been modified, and
> since so far I have only had my hands on non-coachman manuals the pictures of
> the compressors in there look different than the "maybe" compressor I am
> finding in the bathroom...
>
> I now have a link to coachman and I am going there now to see if they have the
> manual, so hopefully my scavenger hunt will be productive.... :) Thanks for
> all the help!
>
> I am still trying to figure out what the green hose is for comming out under
> my back bumper....LOL..... OH MY!


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-- Byron Songer
Full-timing to enjoy the USA
Former owner but still an admirer
GMC paint schemes at -
http://www.songerconsulting.net
Re: [GMCnet] 1978 GMC Royale [message #147010 is a reply to message #147009] Tue, 18 October 2011 23:04 Go to previous messageGo to previous message
tillie1001 is currently offline  tillie1001   United States
Messages: 33
Registered: October 2011
Location: Michigan
Karma: 0
Member

Hi Byron,

Ahaaa! and here I was thinking that was a waterpump.... lol.. I am laughing at myself. I didnt stare at it hard enough to realize it doesnt have water lines running from it....lol.. Btw it is only one not two compressors. When the previous owner updated the interior, they put mattresses down instead of the couch cushions, I assumed when the waterpump was on it was coming from under the mattress because it sounded muffled, that is probably the unit I am seeing in the bathroom, but seems small for a water pump.

yes just one bag on each side, and yes they are in good shape, and holding air well. I have had it for just over two weeks and the psi on the gauge is still reading within a few lbs of when I brought it home, and she doesnt look as if she is sitting any lower.

macerator.... hmmmm I will have to look that up, to figure on how to use and see if it works... Thanks!


Mandie Raymond Clarkston, MI 1978 GMC Royale with rear bath
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