| Author | Message | ||
| JW Smythe (Jwsmythe)
Registered Member Username: Jwsmythe Post Number: 272 Registered: 2-2006 Posted From: 66.118.140.34 Rating: |
Good morning all. It's been a while since I've been in here. My apologies. I'm looking for a little help with my bus. It's a 1982 GMC RTS with a 6V92TA. I'm almost faithful about starting it once a year.  After I fixed the battery problem (if anyone remembers), it started and ran fine. It sat for months, and I started it again. There was a belt squealing for a minute, and then everything started behaving fine again. About two weeks ago, I started it so I could take it out for a drive. The squealing continued, until the belt burnt off.  I have a new belt now, but the idler doesn't appear to be doing its job. It does put some tension on the belt, but I can move it with my fingers, which tells me it isn't anywhere near good enough. That, and when I start it, I can see the drive pulley spinning, but the belt doesn't move. Does anyone happen to have a spare that they'd be willing to part with? According to the book, it is GM part # 15505913 Description "ARM ASM., FAN AND DRIVE IDLER" Also, it didn't seem to be building any air pressure. I don't know if it's a related problem or not. In digging through the shop manuals, I found the air compressor is driven by the cam at the back of the engine, so it shouldn't be a belt problem. When it started previously, squealing at first, and then running normally, it started building up pressure after a while. It could be that some component of the air system just isn't very happy to have been sitting for so long, and isn't seating immediately. Are there any common reasons for this one, or am I going to have to cross my fingers, and hope it resolves itself? Maybe it's time to put an air fitting on, so I can precharge it from a compressor, to push everything back into place. Thanks, JWSmythe | ||
| Jim Shepherd (Rv_safetyman)
Registered Member Username: Rv_safetyman Post Number: 268 Registered: 1-2004 Posted From: 67.142.130.38 Rating: N/A |
Sorry, this was a partial post and I can't find a way to remove it. Full post next message. Jim (Message edited by rv_safetyman on September 16, 2008) | ||
| Jim Shepherd (Rv_safetyman)
Registered Member Username: Rv_safetyman Post Number: 269 Registered: 1-2004 Posted From: 67.142.130.38 Rating: N/A |
JW I am not familiar with the idler system on an RTS, but I suspect that it has an air cylinder as tensioning method. If that is the case, when you solve the air compressor problem, you will have proper tensioning. To test, you could air up the system with an air compressor and see if the belt issue is resolved. Jim Shepherd Evergreen, CO Bus Project at: http://www.rvsafetysystems.com/busproject.htm | ||
| JW Smythe (Jwsmythe)
Registered Member Username: Jwsmythe Post Number: 273 Registered: 2-2006 Posted From: 66.118.140.34 Rating: N/A |
Nope, on this one it's a plain old spring loaded tensioner like a car has. There were some that had a fluid drive for the fan, but they didn't have a belt to worry about. | ||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 561 Registered: 8-2006 Posted From: 207.231.75.253 Rating: N/A |
JW, "ALMOST faithful about starting it once a year?" Shame on you. [Humor] That said, a whole bunch of buses do indeed have air tensioned belts, with a spring assist to keep the belts from falling off with no air. However, IMNSHO, it sounds like you have a driven component that has stuck from lack of use. Please tell us what the belt drives. If the compressor is gear driven off of a camshaft, which is very common, it will be mounted on the BACK of the engine, not the fan end, in your configuration, and won't be connected to your problem. I would put an air fitting and check valve in the output line from the compressor, so that all of the protective devices are allowed to work properly. Since you can get the belt off easily, take it off, and try to turn the pulley(s) that it drives. If you can't turn one, AND you can determine that the idler does have air tensioning, I wouldn't put shop air in the bus and then try to start, for fear of breaking something... (It may alreay be broke, but what the heck.) Post back with what you find, please. George | ||
| niles steckbauer (Niles500)
Registered Member Username: Niles500 Post Number: 858 Registered: 11-2004 Posted From: 97.76.134.179 Rating: N/A |
It could be as simple as a frozen bearing - have you lubed them ever? | ||
| Gus Causbie (Gusc)
Registered Member Username: Gusc Post Number: 731 Registered: 11-2005 Posted From: 208.54.200.144 Rating: N/A |
I go along with George, I try to start mine at least once a month. Once a year is definitely not nearly enough. Hope you solve the problem. | ||
| Sammy (Sammy)
Registered Member Username: Sammy Post Number: 86 Registered: 8-2005 Posted From: 68.237.198.179 Rating: N/A |
You will be able to move the fan with your hand in ONE direction only, it should NOT move in opposite direction.This will tell you if tensioner is still good - as long as there are no seized parts.You need a special bolt to remove the tension for the belt. Once you remove tension, check to see if tensioner pulley or fan hub bearing is seized.Make sure batterys are OFF and rear run and start switches are in OFF position before putting your hands near the fan. Goodluck. | ||
| Bill Gerrie (Bill_gerrie)
Registered Member Username: Bill_gerrie Post Number: 191 Registered: 3-2006 Posted From: 209.50.72.2 Rating: N/A |
JW Is the belt a multi grooved one? I have a new fan drive and idler assembly from an RTS that is off my engine when I bought it. $50 plus shipping and it is yours if it is the same one. Send me a picture and I will see if it is the same one. Bill |
