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Discussion Starter · #1 · (Edited)
OK, so I did the a/c bracket convertion like in this post http://www.cummins-conversion.com/phpBB/viewtopic.php?t=781 but now the belt won't ride on the a/c pulley correctly. It rides one groove width to far forward. I have tried it with washers stacked between mount and a/c comp and without. Tried different alt pulleys....... I mounted a 1994 & up a/c comp and a 1993 & down. Both do the same thing.
I wonder if the Frieghtliner truck used a different a/c comp? Anyone have a part # if yes.
Has anyone else done this same convertion and what did you do about the a/c comp?
 

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1989 Jeep Wagoneer, 360v8, 727, stock for now,
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I hate to say it but you don't have enough belt wrap going over the AC pump. There should be 180 degrees of wrap around the AC pully or it will slip. I've only got 90 degrees wrap on my alternater and it chirps when I turn on a 12V load and it dosen't require near the torque to turn as a AC pump.
Notch the frame, weld a fish plate either inside or outside of the frame near the notch and use the stock Dodge setup.
 

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mine ALMOST covers 5/8th's of the pulley. no chirping here! no belt walking either!
I like it!

Now... Questions:

Does your upper radiator hose fitting come out forward or straight up off the thermostat housing? (It looks like the belt would interfere with forward-exit.)

Think you could do that same basic routing, but keep the tensioner in the "stock" bread truck location? (IE: between fan pulley and alternator?)
 

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OK, so I did the a/c bracket convertion like in this post http://www.cummins-conversion.com/phpBB/viewtopic.php?t=781 but now the belt won't ride on the a/c pulley correctly. It rides one groove width to far forward. I have tried it with washers stacked between mount and a/c comp and without. Tried different alt pulleys....... I mounted a 1994 & up a/c comp and a 1993 & down. Both do the same thing.
I wonder if the Frieghtliner truck used a different a/c comp? Anyone have a part # if yes.
Has anyone else done this same convertion and what did you do about the a/c comp?
Washers in that conversion were to space out from the Oil filter, and *shouldn't* affect front-rear alignment, which is what I think is out on yours. (But could add some "play" in the mounting...)

Are you not able to put the belt in w/o the shift, or is it shifting during engine run? Is the tensioner pulley square to the front of the block, parallel w/ the crank pulley? If it's got a "tilt" relative to the block face or crank pulley, could pull the belt off a bit.

Has the alternator mount been disturbed (other than just flipping the alternator up)? Getting the alternator out of alignment might also contribute to belt shift..
 

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I like it!

Now... Questions:

Does your upper radiator hose fitting come out forward or straight up off the thermostat housing? (It looks like the belt would interfere with forward-exit.)

Think you could do that same basic routing, but keep the tensioner in the "stock" bread truck location? (IE: between fan pulley and alternator?)
it originally pointed forward, (and worked) i swapped for a straight up one.

no, tensioner in "stock" location "chatters". its on the wrong side of tension... imo.
 

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Discussion Starter · #7 ·
Washers in that conversion were to space out from the Oil filter, and *shouldn't* affect front-rear alignment, which is what I think is out on yours. (But could add some "play" in the mounting...)

Are you not able to put the belt in w/o the shift, or is it shifting during engine run? Is the tensioner pulley square to the front of the block, parallel w/ the crank pulley? If it's got a "tilt" relative to the block face or crank pulley, could pull the belt off a bit.

Has the alternator mount been disturbed (other than just flipping the alternator up)? Getting the alternator out of alignment might also contribute to belt shift..
Yep, no back and forth ajustment on the a/c.
I can get everything looking right, but as soon as I fire it up the belt slips forward.
I am running the 22si alt (like in the link above) it looks like its lined up.
This one has me baffled.
Anyone else running this set up?
 

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Discussion Starter · #8 · (Edited)
Machman,
I looked at your picture and you are running a different belt than me. I can see the point about not having enough belt on the pulley the way mine is now. Do you know the part # for the belt you use? and I think in your reply above you said the water neck that comes forward instead of up will work with that belt? I have a stock 1993 neck from a Dodge truck, 5.9
[img=http://img297.imageshack.us/img297/6387/1996bluetruck034cs7.th.jpg] This is a link to my engine. Does it look like that belt would work? Thanks for your time.
 

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Machman,
I looked at your picture and you are running a different belt than me. I can see the point about not having enough belt on the pulley the way mine is now. Do you know the part # for the belt you use? and I think in your reply above you said the water neck that comes forward instead of up will work with that belt? I have a stock 1993 neck from a Dodge truck, 5.9
[img=http://img297.imageshack.us/img297/6387/1996bluetruck034cs7.th.jpg] This is a link to my engine. Does it look like that belt would work? Thanks for your time.
Hey one thing I noticed in the two pictures is your belt is routed differently than his. But He uses the same pulley setup.
 

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it originally pointed forward, (and worked) i swapped for a straight up one.

no, tensioner in "stock" location "chatters". its on the wrong side of tension... imo.
Yeah.. Tensioners always do best if they're last in line on the belt pull. (I was thinking that, if the belt did interfere with the straight-ahead upper rad. hose port, then could use tensioner in "stock" location to try to dodge around it..) Got a belt # for that?? Oh, and is the tensioner / mount plate that you used the same as the "stock" one, just flipped? (I know, I know.. Hit the search..)

Yep, no back and forth ajustment on the a/c.
I can get everything looking right, but as soon as I fire it up the belt slips forward.
I am running the 22si alt (like in the link above) it looks like its lined up.
This one has me baffled.
Anyone else running this set up?
Take a CAREFUL look at your tensioner. It's what "feeds" the belt to the AC Compressor in your setup. If it's off alignment or off square with the belt path, it's gonna push the belt one way or another and might be the cause. I've seen (just replaced the one on my Chevy for this) where the bearing for the pulley on the tensioner gets worn, and the pulley "leans" with respect to the arm / body of the tensioner. This way lies trouble..

Additionally, the slight amount of wrap could be playing a part, too. With so little contact / angle, the AC pulley doesn't have much in the way of "authority" on the belt. More wrap would equal more belt control.

Also, it could be that the tensioner is out of it's "range" and is not sufficiently tensioning the belt. Some tensioners have a range indicated on the body w/ a pointer on the arm. With belt installed, pointer should be between the indicators for usable range. If too tight, leads to premature wear of everything attached to the belt. Too loose, slippage and even belt jump.

Machman,
I looked at your picture and you are running a different belt than me. I can see the point about not having enough belt on the pulley the way mine is now. Do you know the part # for the belt you use? and I think in your reply above you said the water neck that comes forward instead of up will work with that belt? I have a stock 1993 neck from a Dodge truck, 5.9
[img=http://img297.imageshack.us/img297/6387/1996bluetruck034cs7.th.jpg] This is a link to my engine. Does it look like that belt would work? Thanks for your time.
I believe you mean MCInfantry!

My 4BT is still in the P30, waiting on me to get: Parts, money, and courage. (Not to be confused with Lawyers, Guns, and Money.. But then I'm not trying to register the resulting vehicle in any of the "in$pection $tates"..)
 

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Discussion Starter · #11 ·
Sorry about that I did mean MCInfantry.

So MCInfantry What belt are you using? Thanks.

Machman thanks for the info. I believe the tensioner is inline, but I will pay close attention to it next time Im at the shop.
 

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Discussion Starter · #12 ·
So, I looked real close at the pulleys today. The alt is above the a/c and the idler is below. I took a streight edge and layed it across the alt and idler pulleys. The a/c compressor pulley is about a 1/4" set back.
Does anyone know if the pulley can be ajusted out/towards the radiator? or will that cause the front seal to leak? If it can not the only thing I can think is that the bracket/water inlet was machined wrong??
 

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Discussion Starter · #13 ·
I've been going round and round with this a/c. Still won't track right. I did the serp belt install like the picture above from mcinfantry, but still won't work. The only things left it could be are
1. the bracket was machined wrong. (doughtfull)
2. there is another a/c compressor for that application. From Freightliner.

That brings me to my next questions, maybe someone can help.
What a/c comp are pepole using that have the Freightliner bracket?
What application/years of Freightliner did these backets come on?
Does anyone have a part # or mod # for the a/c comp?

Thanks again any help would be great. This has been holding me up from making my first test drive.
 

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I am using this setup with a chevy compressor. I built a 1/4" bracket that bolts to the flat face on the front of the engine bracket. My compressor tracks perfectly with a 6 rib belt. A thought might be to use a thinner belt with the forward groove on the compressor and rearward grooves on everything else. Here is a pic of mine if it helps.
 

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Discussion Starter · #15 ·
Thanks for the picture.
I had thought about mounting the stock compressor with some fab'ed brackets, but I would like to be able to just bolt one on to.
What part of Tx are you in?
 

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NP, Stephenville.
 

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Discussion Starter · #17 ·
Got the a/c serp belt figured out.
There is a difference between a Dodge truck comp and the one I wound up using. The difference is the Dodge has a "mounting distance" of .73" and the compressor I used has a 1.01".
Thier are two I found at OReilly auto parts, part # 58702 and a Sanden # 4667
Hopefully this info will save someone from alot of time trying to find the right a/c compressor for the freightliner bracket
 

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I've been going round and round with this a/c. Still won't track right. I did the serp belt install like the picture above from mcinfantry, but still won't work. The only things left it could be are
1. the bracket was machined wrong. (doughtfull)
2. there is another a/c compressor for that application. From Freightliner.

That brings me to my next questions, maybe someone can help.
What a/c comp are pepole using that have the Freightliner bracket?
What application/years of Freightliner did these backets come on?
Does anyone have a part # or mod # for the a/c comp?

Thanks again any help would be great. This has been holding me up from making my first test drive.
I am using the Compressor for the mid 90's dodge ram.
 
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