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Rear rise in hold [message #260385] Thu, 28 August 2014 19:10 Go to next message
Loffen is currently offline  Loffen   Norway
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Was there ever found a good solution to the problem on early coaches that if you did lower the rear and turned the knob to hold position it would rise after a little while ?
I think I have seen it somewhere but are not able to find the tread that discuss it.


1973 23' # 1848 Sky Blue Glacier called Baby Blue and a 1973 26'-3 # 1460 Parrot green Seqouia Known as the Big Green, And sold my 1973 26'-2 # 581 White Canyon lands under the name Dobbelt trøbbel in Norway
Re: Rear rise in hold [message #260399 is a reply to message #260385] Thu, 28 August 2014 21:13 Go to previous messageGo to next message
midlf is currently offline  midlf   United States
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Loffen wrote on Thu, 28 August 2014 19:10
Was there ever found a good solution to the problem on early coaches that if you did lower the rear and turned the knob to hold position it would rise after a little while ?
I think I have seen it somewhere but are not able to find the tread that discuss it.


Yeah - Slaten's Powerlevel II valves. My rise took only about 5 minutes. I rebuilt the valves twice, no change. Pulled the valves out of the parts transmode, same problems.

Now, with the Powerlevel II valves I have no leaks, droops or inadvertent rises. It will hold whatever position it is set at in hold. If left in travel it stays at the set level. I've left it for up to two weeks with no compressor run on startup. The only change or work on the system was to install the valves.


Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
Re: Rear rise in hold [message #260401 is a reply to message #260385] Thu, 28 August 2014 21:47 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
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Loffen wrote on Thu, 28 August 2014 17:10
Was there ever found a good solution to the problem on early coaches that if you did lower the rear and turned the knob to hold position it would rise after a little while ?
I think I have seen it somewhere but are not able to find the tread that discuss it.


In my experience, it is more likely to leak down and lower the rear end in hold. I suppose anything is possible with leaky Power Level valves. The JR Slaten valves should take care of the problem, as suggested, but adding shut offs at the air bags (and remembering to shut them off as soon as you are leveled up) will certainly do the trick.


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: [GMCnet] Rear rise in hold [message #260412 is a reply to message #260401] Thu, 28 August 2014 23:03 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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The old original valves are cracking and we sell lot of the Slaton Valves.
They are well worth the price.


On Thu, Aug 28, 2014 at 7:47 PM, Carl Stouffer wrote:

> Loffen wrote on Thu, 28 August 2014 17:10
>> Was there ever found a good solution to the problem on early coaches
> that if you did lower the rear and turned the knob to hold position it would
>> rise after a little while ?
>> I think I have seen it somewhere but are not able to find the tread that
> discuss it.
>
>
> In my experience, it is more likely to leak down and lower the rear end in
> hold. I suppose anything is possible with leaky Power Level valves. The
> JR Slaten valves should take care of the problem, as suggested, but adding
> shut offs at the air bags (and remembering to shut them off as soon as you
> are leveled up) will certainly do the trick.
>
> --
> Carl Stouffer
> '75 ex Palm Beach
> Tucson, AZ.
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: Rear rise in hold [message #260413 is a reply to message #260385] Fri, 29 August 2014 00:29 Go to previous messageGo to next message
George Beckman is currently offline  George Beckman   United States
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Loffen wrote on Thu, 28 August 2014 17:10
Was there ever found a good solution to the problem on early coaches that if you did lower the rear and turned the knob to hold position it would rise after a little while ?
I think I have seen it somewhere but are not able to find the tread that discuss it.


I agree with the Slaten valves. That and Sully type bags and my coach goes up faster, down instantly and no longer sags on one side while sitting. The install took not time at all. I had tried two rebuilds on the original valves. First sorta helped. Second, not at all. Now if I could just get the air tank to not leak down when holding for a couple of days I would be a happy camper. I get tired of hearing the pump rattling away before we leave in the morning.


'74 Eleganza, SE, Howell + EBL
Best Wishes,
George
Re: [GMCnet] Rear rise in hold [message #260423 is a reply to message #260412] Fri, 29 August 2014 07:53 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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jimk wrote on Fri, 29 August 2014 00:03
The old original valves are cracking and we sell lot of the Slaton Valves.
They are well worth the price.

While the Slaton valves are an excellent investment, the original valves can be made to work.
To do this you must:
*Completely disassemble the valves and CLEAN everything.
*Inspect them carefully. I have found body flaws that I could fix with epoxy and a crack in one.
*If the mating surfaces are not beautiful, true them with a piece of 400 paper on a FLAT surface like a saw table.
*Watch for flaws in the seating areas of the valves. I was able to refinish these, but it required making a special tool.
*The stock gasket at the case split has a micro-seal issue. If it is coated with Loctite 565, that can be cured.

Mine have been successful (so far).

Or you can just buy the good valves.

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: [GMCnet] Rear rise in hold [message #260439 is a reply to message #260423] Fri, 29 August 2014 09:44 Go to previous message
midlf is currently offline  midlf   United States
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Senior Member
Matt Colie wrote on Fri, 29 August 2014 07:53
jimk wrote on Fri, 29 August 2014 00:03
The old original valves are cracking and we sell lot of the Slaton Valves.
They are well worth the price.

While the Slaton valves are an excellent investment, the original valves can be made to work.
To do this you must:
*Completely disassemble the valves and CLEAN everything.
*Inspect them carefully. I have found body flaws that I could fix with epoxy and a crack in one.
*If the mating surfaces are not beautiful, true them with a piece of 400 paper on a FLAT surface like a saw table.
*Watch for flaws in the seating areas of the valves. I was able to refinish these, but it required making a special tool.
*The stock gasket at the case split has a micro-seal issue. If it is coated with Loctite 565, that can be cured.

Mine have been successful (so far).

Or you can just buy the good valves.

Matt


I believe my problems were in items (2) corrosion, (4) I looked closely by this may have been a problem, (5) I was not aware of this one but agree the cork composition gasket could be a problem. I did items (1) and (3). But the item noted after (or) did the trick. Was the attempted repairs a waste of time. Not if they had worked. In any event I now have a good understanding of how the system works. Now I just have to get my Lenzi adjustable links installed on the height valves.


Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
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