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Topic: Cummins ISL 400 serpentine belt removal / AC compressor belt (Read 3367 times) previous topic - next topic

Cummins ISL 400 serpentine belt removal / AC compressor belt

The serpentine belt is behind the compressor belt. Please see pictures. I need to figure out how to loosen the compressor belt so I can get the serpentine belt out.
If anyone of you had to replace a serpentine belt on Cummins ISL 400 where the AC compressor belt was on the way, any help you can provide will be greatly appreciated.
Thank you,
AL
Former 2003 GV U295 (6230) (2015 - 2025)
Former 94 GV U225 (2013-2016)

Re: Cummins ISL 400 serpentine belt removal

Reply #1 –
An old mechanic taught me this trick. If you can do this safely, use a long screwdriver, carefully touch the metal end to the alternator, put your ear on the end of the plastic handle, you might be able to tell if the clicking is coming from the alternator or not.
Peter and Tammy Fleming
1991 U300 GV 40 - Sold, owned for 4 years
Downsized to Roadtrek Popular 210 class B

Re: Cummins ISL 400 serpentine belt removal

Reply #2 –
Thank you Peter.
I done that with a real Stethoscope, yet i can not tell "hear" 100%
Former 2003 GV U295 (6230) (2015 - 2025)
Former 94 GV U225 (2013-2016)

Re: Cummins ISL 400 serpentine belt removal

Reply #3 –
In order to take off the belt, you must first take off the A/C belt.  I changed all of them myself in about 25 minutes.  You just move the idler pulley with a large 1/2 drive wrench.  If you can't, I'm out of advice.  You'll need a real expert.

Rich
Rich and Peggy Bowman
2002 U270 3610 WTFS, build #5939--"Freedom"
2022 Jeep Grand Cherokee Summit 4xe
SMI AirForceOne brake system
PakCanoe 15

Re: Cummins ISL 400 serpentine belt removal

Reply #4 –
Thank you Rich.
I can loosen up & set a side the serpentine belt without removing the belt for the AC compressor. However in order to remove it completely ... if i ever need to replace it, i will need to remove the compressor belt. I'll figure it out within next couple of weekends.
Former 2003 GV U295 (6230) (2015 - 2025)
Former 94 GV U225 (2013-2016)

Re: Cummins ISL 400 serpentine belt removal / AC compressor belt

Reply #5 –
Quote from: Rich Bowman –
you must first take off the A/C belt.
Rich,
 
Do you just crank down (or up) that large square-headed adjustment screw on the air conditioner compressor, or is there an easier trick?
 
Thanks,
 
Trent
Trent and Jean Eyler
2000  U295  4003  WTFE  ISC  350
Build#5603 MC#17385

Re: Cummins ISL 400 serpentine belt removal / AC compressor belt

Reply #6 –
"You just move the idler pulley with a large 1/2 drive wrench."
If you look at the first picture i have posted (picture name ISL 400) The left most red arrow (somewhat horizontal) points to the pulley. You will see the square hole where the driver wrench goes in, you gentle move it away from the belt ... to the right as you face it.
Former 2003 GV U295 (6230) (2015 - 2025)
Former 94 GV U225 (2013-2016)

Re: Cummins ISL 400 serpentine belt removal / AC compressor belt

Reply #7 –
Sorry I wasn't clearer; I was talking about the air conditioner belt.
 
Trent
Trent and Jean Eyler
2000  U295  4003  WTFE  ISC  350
Build#5603 MC#17385

Re: Cummins ISL 400 serpentine belt removal / AC compressor belt

Reply #8 –
On the A/C belt, you have to loosen the lock nut and then turn the small square head on the end of the bolt.  It doesn't take as many turns as you might think at first glance to get the belt off.

Rich
Rich and Peggy Bowman
2002 U270 3610 WTFS, build #5939--"Freedom"
2022 Jeep Grand Cherokee Summit 4xe
SMI AirForceOne brake system
PakCanoe 15

Re: Cummins ISL 400 serpentine belt removal / AC compressor belt

Reply #9 –
Rich,
 
Thanks. I need to get my Gates green stripe off of there before something bad happens.
 
(Long story, involving one of the top five diesel engine mechanics in the country. They were not supposed to install my new belt because one of the other mechanics determined the A/C compressor was shot. The next group did not read his notes to that effect. Fortunately the pulley stills seems to free wheel, so the Gates belt is going along for the ride.)
 
Trent
 

 

Trent and Jean Eyler
2000  U295  4003  WTFE  ISC  350
Build#5603 MC#17385

Re: Cummins ISL 400 serpentine belt removal / AC compressor belt

Reply #10 –
Quote from: Rich Bowman –
On the A/C belt, you have to loosen the lock nut and then turn the small square head on the end of the bolt.  It doesn't take as many turns as you might think at first glance to get the belt off.

Rich

There's also a mounting bolt with nut that allows the compressor to pivot when adjusted, which may need to be loosened.

Quote from: TulsaTrent –
Fortunately the pulley stills seems to free wheel, so the Gates belt is going along for the ride.)

The clutch not engaging allows it to freewheel, like when the AC is turned off.

Re: Cummins ISL 400 serpentine belt removal / AC compressor belt

Reply #11 –
You could also just unplug the wire to the clutch and it will then freewheel until you get the system repaired.  The plug is about 6" from where the wire comes out of the clutch.

Rich
Rich and Peggy Bowman
2002 U270 3610 WTFS, build #5939--"Freedom"
2022 Jeep Grand Cherokee Summit 4xe
SMI AirForceOne brake system
PakCanoe 15

Re: Cummins ISL 400 serpentine belt removal / AC compressor belt

Reply #12 –
Rich,
"On the A/C belt, you have to loosen the lock nut and then turn the small square head on the end of the bolt.  It doesn't take as many turns as you might think at first glance to get the belt off."

You may reach out over the internet and smack me back of my head :-[  sorry but I did not understand. Do you see the "lock nut" & the "small square head" in my just attached pictures?

I think i am being a bit timid before i loosen the compressor belt up ... they just installed it nicely & with 12 month warranty .. so i want to make sure what i loosen up i can put it back the same.
Thank you,
AL
Former 2003 GV U295 (6230) (2015 - 2025)
Former 94 GV U225 (2013-2016)
 

Re: Cummins ISL 400 serpentine belt removal / AC compressor belt

Reply #13 –
Al,

That looks like the right bolt and nut.  As Traveling Man pointed out, you may also have to loosen a second bolt that the compressor pivots on.  I did not have to do that.  Mine was able to pivot.

If you're that worried, just unplug the one wire to the clutch until you have the compressor worked on.  After you unplug, you can check to make sure it won't engage by trying the A/C on max for a minute with the engine running.  I'm pretty sure the dash A/C is like a car A/C and will try to run in all positions except straight vent.

Rich
Rich and Peggy Bowman
2002 U270 3610 WTFS, build #5939--"Freedom"
2022 Jeep Grand Cherokee Summit 4xe
SMI AirForceOne brake system
PakCanoe 15