GMCforum
For enthusiast of the Classic GMC Motorhome built from 1973 to 1978. A web-based mirror of the GMCnet mailing list.

Home » Public Forums » GMCnet » Changing belts
Changing belts [message #357631] Mon, 10 August 2020 21:30 Go to next message
aaronanalog is currently offline  aaronanalog   United States
Messages: 23
Registered: February 2016
Location: Full Time Traveling
Karma: -2
Junior Member
How do I loosen the belts on a 403 ? I’m putting on a new alt belt and got that one. I just can’t find the pivot bolts on the AC or the power steering.
Re: Changing belts [message #357637 is a reply to message #357631] Tue, 11 August 2020 07:42 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
Messages: 2324
Registered: October 2010
Location: St. Cloud, MN
Karma: 5
Senior Member
I am not really too familiar with the 403... but I did not think it is that far off then the 455.

you have to tighten the power steering belt 1st, then the alternator belt in that order.

http://www.gmcmhphotos.com/photos/power-level-valve-fitting/p66388-power-steering-pump-mount.html


the powersteering and A/C brackets are overtly complicated. Power steering on my 455, has a few bolts that have to be loosened up, and I prefer to have the wheel well liner, and I get some from there, I think one from below, and then the actual tighting I do from the engine compartment. I have a craftsman long prybar, that I cut the flat end off of. it ends up being a square end that barely fits between the pully and bracket, but it catches a flat notch that sticks out from the power steering bracket, and a flat spot on the nose of the power steering pump. basically straight down between the thermostat housing and the A/C. it is a tight fit, but when it fits- it is perfect, and does not take much to pull on the bar to set the belt. the bolt I lock it down with is a deep well 9/16" socket that goes through a hole in pully. Then you have to get under, and to the side to get all the other bolts that have to be loose for pump to move.

see #10 washer in that diagram. that is needed, and make sure it is in place.


I have not worked on the A/C enough to remember that one, but again, taking out the wheel well liner makes seeing and doing on that easier as well.

here is a photo of that:
http://www.gmcmhphotos.com/photos/miscellaneous-stuff/p51610-some-1978-iso-drawings-from-the-manuals.html







Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/

[Updated on: Tue, 11 August 2020 07:43]

Report message to a moderator

Re: Changing belts [message #357639 is a reply to message #357631] Tue, 11 August 2020 08:37 Go to previous message
6cuda6 is currently offline  6cuda6   Canada
Messages: 975
Registered: June 2019
Karma: -6
Senior Member
Power steering - one nut behind the pump and one behind the pulley itself (if you stick your finger in the holes of the pulley you'll find it.

AC - bellow the compressor on the support arm and then the 2 pivots front/back off the motor support.


aaronanalog wrote on Mon, 10 August 2020 22:30
How do I loosen the belts on a 403 ? I’m putting on a new alt belt and got that one. I just can’t find the pivot bolts on the AC or the power steering.


Rich Mondor, Brockville, ON 77 Hughes 2600
Previous Topic: [GMCnet] looking for an engine hoist in Southern California
Next Topic: Unnecessary complication
Goto Forum:
  


Current Time: Sat Nov 02 20:20:55 CDT 2024

Total time taken to generate the page: 0.00818 seconds