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[GMCnet] Two ideas for our GMCs [message #329056] Sun, 11 February 2018 13:43 Go to next message
glwgmc is currently offline  glwgmc   United States
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Having now lived for close to a year with this wonderful Prevost Country Coach Motorhome there are two things I would implement if we ever have another GMC.

The first is the generator sits on four small air bags that greatly reduce both vibration and noise transmission. The bags sit between the generator mounts and the coach chassis. They are not very expensive and apparently readily available. They would be easy to plumb in either by T off one of the compressor/air tank outlets with check valve, or by adding another inexpensive 12vdc compressor just for that task. The air volume is quite low so even a small displacement compressor would work well. Plumb in an air pressure regulator so you can dial in the desired air pressure. Wire the compressor through a relay powered off the positive post on the gen coil. That way the compressor would come on only when the gen is running and only if the air pressure regulator called for air. Most of the time it would only run for a few minutes at initial gen start and then shut off once the air bags were inflated. One could also power a 120vac small compressor (think small trim nail gun compressor) off of the 120vac output from the generator with the same result.

The second idea taken from the Prevost also involves air. The Prevost uses small air bellows to tension the belts powering the side mounted engine cooling fan. With a simple to make bracket and a pulley to push on the belts, it looks like one of these could easily tension the alternator and/or AC belts. With the air off the belts would be slack enough to replace by hand with no tools. With air tensioning, belt squeak and stretch would automatically be compensated and replacing a broken belt would become an easy no-tool five minute job. The ones Prevost use cost less than $50.

Jerry

Jerry Work
The Dovetail Joint
Fine furniture designed & hand crafted
in the 1907 former Masonic Temple building
in historic Kerby, OR
http://jerrywork.com


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Jerry & Sharon Work
78 Royale
Kerby, OR
Re: [GMCnet] Two ideas for our GMCs [message #329057 is a reply to message #329056] Sun, 11 February 2018 14:20 Go to previous messageGo to next message
pjburt is currently offline  pjburt   United States
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Hmmm... excellent ideas. Especially the belt tension-er.
Thanks Jerry


Patti & Jerry Burt
73 Gmc 26' Canyon Lands - 77 Palm Beach Members: FMCA - GMCMI - GMCWS - Pacific Cruisers - 49ers
Re: [GMCnet] Two ideas for our GMCs [message #329060 is a reply to message #329057] Sun, 11 February 2018 15:39 Go to previous messageGo to next message
Les Burt[1] is currently offline  Les Burt[1]   United States
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Pneumatic tensioners would require air pressure prior to start-up. Not a big deal, but a required discipline to adopt to avoid throwing a belt.

Les Burt
Montreal
'75 Eleganza 26'


> On Feb 11, 2018, at 3:20 PM, Jerry Burt wrote:
>
> Hmmm... excellent ideas. Especially the belt tension-er.
> Thanks Jerry
> --
> Patti & Jerry Burt
> 73 Gmc 26' Canyon Lands -
> 77 Palm Beach
> Members: FMCA - GMCMI - GMCWS - Pacific Cruisers - 49ers
>
> _______________________________________________
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Re: [GMCnet] Two ideas for our GMCs [message #329068 is a reply to message #329060] Sun, 11 February 2018 22:35 Go to previous messageGo to next message
Hal StClair   United States
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Location: Rio Rancho NM
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Air tensioners do work for Prevost but they're used on low RPM motors vs gas motors that fast idle at near diesel governed speeds. If you've ever seen the belts flailing away before air tensions them you'd swear they'd be pitched. I'd think a simple spring loaded tensioner could be incorporated with little effort. Of course it would need more tension than the typical serpentine tensioner but I'd suspect it should be quite doable. KISS still rings true IMHO. Hal

1977 Royale 101348, 1977 Royale 101586, Diesel powered, 1975 Eleganza II, 101230, 1974 Eagle Bus 45',w/slideout, Rio Rancho, NM
Re: [GMCnet] Two ideas for our GMCs [message #329069 is a reply to message #329060] Sun, 11 February 2018 22:48 Go to previous messageGo to next message
Bullitthead is currently offline  Bullitthead   United States
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A pretension spring would take care of the slack at starting on a gasoline engine. I had to fab up a bracket on my uncle's 350 Olds diesel to put a tensioner on the back side of the alternator belt because the power pulse of the engine would throw the belt off at certain rpms. The unsupported distance in the belt allowed the resonance wave to attain almost 3 inches peak to peak no matter how tight the belt was. It solved the problem but looked homemade.

Got any pics of those air powered tensioners?


Terry Kelpien ASE Master Technician 73 Glacier 260 Smithfield, Va.
Re: [GMCnet] Two ideas for our GMCs [message #329070 is a reply to message #329069] Sun, 11 February 2018 23:16 Go to previous message
Hal StClair   United States
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Registered: March 2013
Location: Rio Rancho NM
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There are a couple of diff
erent types employed. One style is simply a small air billows/bag. Another looks like a typical air cylinder. Some of the configurations simply move a chive/pulley against the belts others move an assembly which may have either a compressor or auxiliary alternator mounted. Nothing too high tech for sure. Hal


1977 Royale 101348, 1977 Royale 101586, Diesel powered, 1975 Eleganza II, 101230, 1974 Eagle Bus 45',w/slideout, Rio Rancho, NM
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