The GMC was in a wreck. So I'm hoping that the unit may work. There is a small manifold made up of fittings, pressure gauge, and an 12volt controlled valve. One for each compressor. It's identical to mine in every way except for these added parts. Bob Bunahugh Late 78 Royale
Picked up a complete late 78- 2 compressor assembly at a salvage yard for $10. What's the option on it for?
- Thread starter Bob Dunahugh
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Gotta get those TZE numbers when you're shopping...
> The GMC was in a wreck. So I'm hoping that the unit may work. There is a
> small manifold made up of fittings, pressure gauge, and an 12volt
> controlled valve. One for each compressor. It's identical to mine in every
> way except for these added parts. Bob Bunahugh Late 78 Royale
> _______________________________________________
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--
Michael Beaton
1977 Kingsley 26-11
1977 Eleganza II 26-3
Antigonish, NS
Life is too short to hold a grudge; slash some tires and call it even !
> The GMC was in a wreck. So I'm hoping that the unit may work. There is a
> small manifold made up of fittings, pressure gauge, and an 12volt
> controlled valve. One for each compressor. It's identical to mine in every
> way except for these added parts. Bob Bunahugh Late 78 Royale
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Michael Beaton
1977 Kingsley 26-11
1977 Eleganza II 26-3
Antigonish, NS
Life is too short to hold a grudge; slash some tires and call it even !
A dual comressor asembly, stock? For dash air?
Id be interested in seeing pics of this.
Never seen one.
--
76 Glenbrook
Id be interested in seeing pics of this.
Never seen one.
--
76 Glenbrook
I believe what you have is a Cinnabar Modification, designed by Wes Caughlin, to the EL II System, a pretty desirable mod. The 12 volt valve is
actually an adjustable pressure limit switch. As designed by GM, pressure was limited only by what the compressors would put out. When new the
pressure could go quite high in RAISE, resulting in problems. The switches were supposed to be adjusted to 120psi limit. This mod also replaced the
shutoff solenoids with ones that did not allow leakage in either direction, & also added the pressure gauges. I have documentation for this, but
won't be home to access it for several days. Then I'll try to put it on the photo site.
--
John Shutzbaugh, Vacaville, CA, ncserv;
77 Eleganza, bought it new, can't blame PO, and
78 Buskirk stretch, "What were we thinking?"
actually an adjustable pressure limit switch. As designed by GM, pressure was limited only by what the compressors would put out. When new the
pressure could go quite high in RAISE, resulting in problems. The switches were supposed to be adjusted to 120psi limit. This mod also replaced the
shutoff solenoids with ones that did not allow leakage in either direction, & also added the pressure gauges. I have documentation for this, but
won't be home to access it for several days. Then I'll try to put it on the photo site.
--
John Shutzbaugh, Vacaville, CA, ncserv;
77 Eleganza, bought it new, can't blame PO, and
78 Buskirk stretch, "What were we thinking?"
Bob - any other good parts on that '78 salvage coach?
--
Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
--
Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
Bob, the EL II compressor/desiccant assembly was state of the art stuff
when they were used in the late 77 and 78 coaches. There are two weak
points (times two) The first one is the permanent magnet fields in the
motors. They fade away over time, and not much the average owner can do
about it. The motors just develop less and less torque as they age out.
Newer permanent magnets use some rare earth elements, and retain their
strength for many years. Like the ones used in the Vi-Air compressors. Get
a screwdriver near the motor and they will stick right to them.
The second weak point is the exhaust valves built into the compressor
cylinder head(s) They are not servicible and are a common source of air
leaks. Not much can be done for them, except, like Cinabar and some others
have done, add a downstream solenoid controlled valve. More complexity to
an already complex system. Not the way I like to go. I subscribe to the
K.I.S.S. principle. The least complex system USUALLY winds up being the
most reliable.
Both of those weaknesses I described are resolved by replacement of the
compressors, or a complex workaround. Compressors SIMILAR TO, but not
exactly the same, we're used in a number of Oldsmobile Silouette vans, as
well as Pontiac and chev vans that share the platform with Olds. No current
production vehicles that I am aware of use an exact replacement compressor.
Rotsa Ruck finding something. Same for the height control valves. Some are
close to the same, but not exact. They can be improvised to work. I have a
bunch of pieces for the EL II. Let me know if I can help you with used
parts. Shipping costs.
Jim Hupy
Bob - any other good parts on that '78 salvage coach?
--
Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
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when they were used in the late 77 and 78 coaches. There are two weak
points (times two) The first one is the permanent magnet fields in the
motors. They fade away over time, and not much the average owner can do
about it. The motors just develop less and less torque as they age out.
Newer permanent magnets use some rare earth elements, and retain their
strength for many years. Like the ones used in the Vi-Air compressors. Get
a screwdriver near the motor and they will stick right to them.
The second weak point is the exhaust valves built into the compressor
cylinder head(s) They are not servicible and are a common source of air
leaks. Not much can be done for them, except, like Cinabar and some others
have done, add a downstream solenoid controlled valve. More complexity to
an already complex system. Not the way I like to go. I subscribe to the
K.I.S.S. principle. The least complex system USUALLY winds up being the
most reliable.
Both of those weaknesses I described are resolved by replacement of the
compressors, or a complex workaround. Compressors SIMILAR TO, but not
exactly the same, we're used in a number of Oldsmobile Silouette vans, as
well as Pontiac and chev vans that share the platform with Olds. No current
production vehicles that I am aware of use an exact replacement compressor.
Rotsa Ruck finding something. Same for the height control valves. Some are
close to the same, but not exact. They can be improvised to work. I have a
bunch of pieces for the EL II. Let me know if I can help you with used
parts. Shipping costs.
Jim Hupy
Bob - any other good parts on that '78 salvage coach?
--
Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
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Thanks guys so much for helping me understand this late 78 air ride system. And hopefully that Cinnabar add on helps. That add on was mounted on the wall above the compressors. Last night I mounted the Cinnabar parts on the compressor assembly. Tomorrow I'm putting plug in connectors on both wire bundles that go the compressor assembly. This way I can install my assembly to see if it works in a simple way.. If not. Now I'll have a test unit to check compressors out of the cabinet there in. As I've longer wires. If anyone wants a photo. Let me know. Bob Dunahugh Late 78 Royale Forgot. So the 2 wires going into the compressor head. Open a valve ?
The GMC was in a wreck. So I'm hoping that the unit may work. There is a small manifold made up of fittings, pressure gauge, and an 12volt controlled valve. One for each compressor. It's identical to mine in every way except for these added parts. Bob Bunahugh Late 78 Royale
The GMC was in a wreck. So I'm hoping that the unit may work. There is a small manifold made up of fittings, pressure gauge, and an 12volt controlled valve. One for each compressor. It's identical to mine in every way except for these added parts. Bob Bunahugh Late 78 Royale
Yes, those wires are for the exhaust valve, actuated by the leveling sensor in the wheel wells or the "Lower" switch at the driver's control panel.
The leveling sensors are active when the switch up front is in "Travel". These sensors then turn their respective pump on (thru a relay), or activate
the exhaust valve, to maintain ride height. Only one line goes to each side, cutting down on the large number of leak sources of previous systems.
Not a bad idea at the time, but as James Hupy pointed, out those sensors & pump/valve units are now very expensive and there are no easily adaptable
replacements available.
Hope your salvaged units check out ok so you can move on.
--
John Shutzbaugh, Vacaville, CA, ncserv;
77 Eleganza, bought it new, can't blame PO, and
78 Buskirk stretch, "What were we thinking?"
The leveling sensors are active when the switch up front is in "Travel". These sensors then turn their respective pump on (thru a relay), or activate
the exhaust valve, to maintain ride height. Only one line goes to each side, cutting down on the large number of leak sources of previous systems.
Not a bad idea at the time, but as James Hupy pointed, out those sensors & pump/valve units are now very expensive and there are no easily adaptable
replacements available.
Hope your salvaged units check out ok so you can move on.
--
John Shutzbaugh, Vacaville, CA, ncserv;
77 Eleganza, bought it new, can't blame PO, and
78 Buskirk stretch, "What were we thinking?"
Sort of like this
http://bdub.net/gmcmotorhome.info/levelsch.htm
Schematics
> Yes, those wires are for the exhaust valve, actuated by the leveling
> sensor in the wheel wells or the "Lower" switch at the driver's control
> panel.
> The leveling sensors are active when the switch up front is in "Travel".
> These sensors then turn their respective pump on (thru a relay), or activate
> the exhaust valve, to maintain ride height. Only one line goes to each
> side, cutting down on the large number of leak sources of previous systems.
>
> Not a bad idea at the time, but as James Hupy pointed, out those sensors &
> pump/valve units are now very expensive and there are no easily adaptable
> replacements available.
>
>
> Hope your salvaged units check out ok so you can move on.
> --
> John Shutzbaugh, Vacaville, CA, ncserv;
> 77 Eleganza, bought it new, can't blame PO, and
> 78 Buskirk stretch, "What were we thinking?"
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://bdub.net/gmcmotorhome.info/
Alternator Protection Cable
http://bdub.net/gmcmotorhome.info/APC.html
http://bdub.net/gmcmotorhome.info/levelsch.htm
Schematics
> Yes, those wires are for the exhaust valve, actuated by the leveling
> sensor in the wheel wells or the "Lower" switch at the driver's control
> panel.
> The leveling sensors are active when the switch up front is in "Travel".
> These sensors then turn their respective pump on (thru a relay), or activate
> the exhaust valve, to maintain ride height. Only one line goes to each
> side, cutting down on the large number of leak sources of previous systems.
>
> Not a bad idea at the time, but as James Hupy pointed, out those sensors &
> pump/valve units are now very expensive and there are no easily adaptable
> replacements available.
>
>
> Hope your salvaged units check out ok so you can move on.
> --
> John Shutzbaugh, Vacaville, CA, ncserv;
> 77 Eleganza, bought it new, can't blame PO, and
> 78 Buskirk stretch, "What were we thinking?"
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://bdub.net/gmcmotorhome.info/
Alternator Protection Cable
http://bdub.net/gmcmotorhome.info/APC.html
