I'm wanting to remove the Air Pump off my 1991 318 Dakota with A/C (don't worry, I don't require any emissions testing here) and just have one question, as I can't seem to be able to track it down anywhere here. Does anyone know what size of belt is needed to run everything once the Air Pump has been removed? Thanks!

 

This is just speculation, but I would think it would be close to if not the same length as the 92 and up belts that did not have the smog pump which IIRC are 97.5" and 7 ribs. I think you probably have a 6 rib belt, but should be easy to find one close to 97.5" in a 6 rib. Or you can make a guesstimate of what you think the length should be and buy several belts with a few shorter than and a few longer than your guesstimate, and return the ones you don't use.

If you don't already know how to read belt lengths it is pretty easy.
In most cases they are labeled for example : 975K7
the first 3-4 digits are the length with one decimal point i.e. 97.5"
the last tells the number of ribs i.e. k7= 7 ribs K6= 6 ribs

in the case of goodyear and dayco they use a number such as 4060975 or 5060975
the 40 or 50 prefix is not important (think they use it to identify grade of belt)
the 6 is the number of ribs (6 = 6 ribs 7 = 7 ribs)
the last 4 digits are the length with one decimal point just like the other brands.

Hope that helps, and sorry for the long post

 

91 had the v-bet setup. atleast that's what my 91 has. not sure on the belt length though. i took mine off nd havan't had the chance to see what all fits without it yet

 

doesn't that belt run "just" the smog pump? Even if it does also go around the water pump I think theres a 2nd belt that will still be there to drive the water pump if you pull that belt...

 

The V6's got a V Belt that had a separate belt for the Air Pump.

The V8's had a ribbed belt that drove everything.

Thanks for the help DakotaRT!

 

on a 91? That was still the "LA" engine not the Magnum, maybe the 4 bangers had a serpentine style belt but I didnt think that the V6s or the V8s got the serpentine style til they converted to the Magnum series engine? theres a 91 318 Dakota in the local yard I gotta have a look next time i am there

 

V8's definately had it, I have one sitting in my yard. I can take a picture of it if you want to see it.

EDIT: And no, it isn't a Magnum engine. It is still TBI.

 

Yes correct the V8 1990-91 use a serpentine belt.



The 90-91 V6 use a V-Belt system.



Since you want to delete the air pump, I suggest to take some measurements of what size belt you need, then look up specs and find a belt that is what you need. www.napaonline.com has lots of specs for most of their parts.

 

if yours is like the top drawing looks like you will have to go around the bottom idler on the opposite side as shown in the drawings for it to work..and hope it clears the top idler...or take out both idlers and run straight from the crank to the alt..???. not as easy as it sounds. i would get a rope and run it around all the pulleys to get the length and try to match up at a parts store.