|
|
|
|
Re: [GMCnet] A/C bypass pulley [message #241877 is a reply to message #241649] |
Sat, 01 March 2014 11:03 |
|
ljdavick
Messages: 3548 Registered: March 2007 Location: Fremont, CA
Karma: -3
|
Senior Member |
|
|
I have the dual pulley on my coach as well. Keep in mind that there were already two belts pulling in that direction, so I doubt the force has increased with both belts routing around the alternator.
It seems to me that the dual belts routing around the PS Pump and the alternator may actually require less tension than a single belt on the alternator. As an aid to tensioning a single alternator belt Jim K sells the threaded tensioner <http://www.appliedgmc.com/prod.itml/icOid/1106>. The need for this, I feel, comes from the newer 100 amp units many of us have put on the coach. For me starting always included a squealing belt. It was as tight as I was comfortable getting it, so I tried the double pulley. No more squeal and I was no longer concerned about disturbing others when starting the coach early or late in the day.
JWID
Larry Davick
A Mystery Machine
1976(ish) Palm Beach
Fremont, CA
On Feb 27, 2014, at 9:40 AM, Jp Benson wrote:
> John & Matt,
>
> Thanks for the input. My only concern is uneven loading on the Milodon
> water pump bearings. I've got the dual alternator/power steering belts
> on one side and nothing to counterbalance on the other. If there was a
> simple A/C bypass setup I'd put it on.
>
> Thanks,
> JP
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Larry Davick
A Mystery Machine
1976(ish) Palm Beach
Fremont, Ca
Howell EFI + EBL + Electronic Dizzy
|
|
|
|
Re: [GMCnet] A/C bypass pulley [message #241897 is a reply to message #241896] |
Sat, 01 March 2014 14:53 |
James Hupy
Messages: 6806 Registered: May 2010
Karma: -62
|
Senior Member |
|
|
JP, if you still have your ac compressor and the front bearings on the
clutch end are good, just disconnect the wires from the ac controls and run
the stock ac belt. You can tighten it as much as you feel will load the
waterpump in the opposite way from the alternator. As long as your ac
clutch is disengaged, all you have left is an idler pulley.
Jim Hupy
Salem, Or
78 GMC Royale 403
On Mar 1, 2014 12:44 PM, "Jp Benson" <chocomo99@yahoo.com> wrote:
> Larry,
>
> Thanks. I do have the 100 amp alternator. It's just that both belts
> are loading the water pump bearing in the same direction while the A/C
> belt would pull in the opposite direction to counteract that force.
> Maybe I'm over concerned but I've owned many GM vehicles over the
> years. Most of them have had water pump failures. A couple of them at
> very low mileage. So if there was something simple I could do that
> might prevent or delay another failure it would be worthwhile in my
> judgement. I do plan to re-install the A/C later but I'm not sure when.
>
> Just for fun, I made my own version of the belt tensioner from some junk
> I had laying around. A bit clunky but it does work.
>
> http://www.gmcmhphotos.com/photos/g6341-belt-tensioner.html
>
> JP
>
> On 3/1/2014 12:03 PM, Larry Davick wrote:
> > I have the dual pulley on my coach as well. Keep in mind that there
> were already two belts pulling in that direction, so I doubt the force has
> increased with both belts routing around the alternator.
> >
> > It seems to me that the dual belts routing around the PS Pump and the
> alternator may actually require less tension than a single belt on the
> alternator. As an aid to tensioning a single alternator belt Jim K sells
> the threaded tensioner <http://www.appliedgmc.com/prod.itml/icOid/1106>.
> The need for this, I feel, comes from the newer 100 amp units many of us
> have put on the coach. For me starting always included a squealing belt.
> It was as tight as I was comfortable getting it, so I tried the double
> pulley. No more squeal and I was no longer concerned about disturbing
> others when starting the coach early or late in the day.
> >
> > JWID
> >
> > Larry Davick
> > A Mystery Machine
> > 1976(ish) Palm Beach
> > Fremont, CA
> >
> >
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
|
|
|
Re: [GMCnet] A/C bypass pulley [message #241900 is a reply to message #241896] |
Sat, 01 March 2014 15:24 |
|
Matt Colie
Messages: 8547 Registered: March 2007 Location: S.E. Michigan
Karma: 7
|
Senior Member |
|
|
Jp Benson wrote on Sat, 01 March 2014 15:44 | Larry,
Thanks. I do have the 100 amp alternator. It's just that both belts are loading the water pump bearing in the same direction while the A/C belt would pull in the opposite direction to counteract that force.
Maybe I'm over concerned but I've owned many GM vehicles over the years. Most of them have had water pump failures. A couple of them at very low mileage. So if there was something simple I could do that might prevent or delay another failure it would be worthwhile in my judgement. I do plan to re-install the A/C later but I'm not sure when.
Just for fun, I made my own version of the belt tensioner from some junk I had laying around. A bit clunky but it does work.
JP
|
JP, actually, the belt tensions are vector-additive. So, the biggest load vector on the pump bearings is going to be somewhere close to 5 O'clock looking at the front of the engine. Without the A/C belt, it will be less and closer to 4.
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] A/C bypass pulley [message #241955 is a reply to message #241641] |
Sat, 01 March 2014 21:10 |
GMCNUSA
Messages: 283 Registered: August 2006 Location: Indianapolis, IN
Karma: 0
|
Senior Member |
|
|
Jp Benson wrote on Thu, 27 February 2014 11:49 | Does anyone know of a bolt on A/C bypass pulley for the 455?
Thanks,
JP
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
|
The PO removed all the dash A/C components and my belt squeeled alot. I built a bracket and idler pulley in the position of the A/C compressor and all squeeling stopped. On my coach the squeeling was caused when radiator fan engaged putting more load on fan pulley.
Larry Dilk
Indianapolis, IN
76 Eleganza II
Patterson 455,Turbo City TBI,
Just LOVE It!
|
|
|
|
Re: [GMCnet] A/C bypass pulley [message #242079 is a reply to message #241649] |
Sun, 02 March 2014 19:33 |
Bob de Kruyff
Messages: 4260 Registered: January 2004 Location: Chandler, AZ
Karma: 1
|
Senior Member |
|
|
Jp Benson wrote on Thu, 27 February 2014 10:40 | John & Matt,
Thanks for the input. My only concern is uneven loading on the Milodon
water pump bearings. I've got the dual alternator/power steering belts
on one side and nothing to counterbalance on the other. If there was a
simple A/C bypass setup I'd put it on.
Thanks,
JP
On 2/27/2014 12:17 PM, John R. Lebetski wrote:
>
> AC is it's own belt in stock form. I'm confused unless you are serpentine.
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
|
You don't need to "counter balance" the water pump bearings.
Bob de Kruyff
78 Eleganza
Chandler, AZ
|
|
|
|