Author Topic: ISB 6.7 "short" belt.  (Read 772 times)

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Offline oscar

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ISB 6.7 "short" belt.
« on: January 16, 2019, 10:45:11 AM »

New to this forum, not new to forums.

I have a 2017 Berkshire 38A which has the 6.7L ISB engine, mine a 340.

I carry a spare belt, just in case. But, it appears a large number of belt failures (and the resulting stop on the side of the road) are due to the AC compressors seizing. You CAN mount a shorter belt and take the AC compressor out of the loop.

Does anyone here know the size/part # of the shorter belt?


Offline ziggyh

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Re: ISB 6.7 "short" belt.
« Reply #1 on: January 16, 2019, 07:20:06 PM »
Serpentine Belts are usually measured by their circumstances, so use a string or a cloth measuring tape around your pulleys the way the belt is to be routed. Then measure the length of the string, get one that is the next size smaller so the tensioner can tension the belt 

I am assuming you have a serpentine belt with an automatic tensioner. The tensioner usually will have two marks on it to indicate it's range of operation. Target in the middle of those marks if they are present

If your old belt has a pk number on it you can also use that. If for example the number is 8pk1500 it indicates it has 8 ribs on it and is a metric belt 1500 mm in length.

V belts are measured much the same way but at the top of the pulley groove.
« Last Edit: January 16, 2019, 07:38:57 PM by ziggyh »

2007 Revolution LE

Offline David.e.atherton

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Re: ISB 6.7 "short" belt.
« Reply #2 on: January 17, 2019, 06:43:15 AM »
ZiggyH and Oscar, think I can come up with belt number for you because I just made
That change 2 weeks ago but will be later today when I return back. Cummins has been
aware of the problem and add on pulley to fan hub for a vee belt setup to AC compressor.
Ask Dave Dave Atherton Retired Cat Mechanic