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6.7 fan pulley on a 5.9 engine, will it work?

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2004.5 Drive Train Howl

Transmission failing at 22k miles?

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Well, in short, I screwed up. The 6. 7 damper does indeed contact the 5. 9 fan pulley:eek:



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You can see that it touches by the slightest bit.



Here's the 5. 9 damper and 6. 7 pulley:

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6. 7 pulley:

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5. 9 pulley:

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Basically, I was more concerned with the actual mounting bracket as well as the size of the wheels; the thickness of each never even dawned on me. As you can see, the 6. 7 pulley is 1/4" thinner than the 5. 9 pulley, and this is what creates the clearance needed between the larger damper and the pulley. The 5. 9 pulley is 1 3/4" thick vs. 1 1/2" thick for the 6. 7 pulley. I apologize for the mistake.



Here is the 5. 9 damper held in front of the 6. 7 damper:

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I was able to pull the 5. 9 damper off, and of course I started to round one of the bolt heads on the 6. 7 damper, so I said screw it and didn't mess with it anymore. The only weight I got for the 5. 9 damper was 14. 8 lbs, which may or may not be accurate. The only scale I have is a joke bathroom scale that I can't seem to get to work:confused: It flashed zeros at me 5 times and the only number I managed to get was when I pushed on it some and got the 14. 8...



The 6. 7 damper is 9 9/16" across.

The 5. 9 damper is 8 3/4" across.



Hopefully this clears up the mystery (5. 9 damper/5. 9 pulley. 6. 7 damper/6. 7 pulley)



I just now had the chance to carefully look at my fan pulley and the pics above. My 2007 5. 9 has the 6. 7 "short" fan pulley on it (the hub sticks out past the front of the pulleys belt surface). I also noted that from the pic of the 6. 7 damper, that the back side of the damper has a 30* bevel at the outer circumference to gain extra clearance with the larger dia.

I can't thank you enough 'strokeThis_'07 for your help on this issue.

It's looking like the 2007 5. 9 engines had the 6. 7 fan pulleys installed so the factory would not have to have 2 different pulleys in stock when the 6. 7 production run started. My engine build date was 7-7-06.

Now, do I get a 6. 7 damper, or the fluidamper?

Has any one installed the 6. 7 damper on their 5. 9?

Has any one installed a Fluidamper on a 2007 5. 9?
 
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Hmm, I didn't even think about popping the hood on my 07. Well... . I can try to pull that 6. 7 damper. If I ruin the one bolt, oh well, I have four extras
 
Hmm, I didn't even think about popping the hood on my 07. Well... . I can try to pull that 6. 7 damper. If I ruin the one bolt, oh well, I have four extras



Plus, if you do, I'll still buy you that case of beer I offered up!!! :-laf



Also, by and by, if you end up with an extra 6. 7 damper and/or pulley, after you are all done with your engine swap, I am more then willing to buy it from you. Oo.
 
stroke,

Sorry about the loss of all the photos. . they were extremly well done and useful!!!

Any update on the fitment of the 6. 7 damper on the 5. 9??
 
This afternoon I installed the 6. 7 damper and fan pulley on the 5. 9 in my '04. 5 and can report that it appears everything will play well. The bonus is that the belt can be changed without removing any pulleys, although it may take a little more effort. I pulled the fan and shroud out in preparation for a cam swap while I had my injectors rebuilt, so I installed the new damper and fan pulley and fitted the belt with those things removed. It seems to work best to turn the belt parallel to the engine and then turn the fan pulley to help it squeeze through the small gap between the dampener and fan pulley. The new damper is also marked with TDC from the factory and it appears the 12 o'clock position is where it needs to be. When the fan and shroud are put back on I will see how easy the belt comes off and on.

Godspeed,
Trent
 
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This afternoon I installed the 6. 7 dampener and fan pulley on the 5. 9 in my '04. 5 and can report that it appears everything will play well. The bonus is that the belt can be changed without removing any pulleys, although it may take a little more effort. I pulled the fan and shroud out in preparation for a cam swap while I had my injectors rebuilt, so I installed the new dampener and fan pulley and fitted the belt with those things removed. It seems to work best to turn the belt parallel to the engine and then turn the fan pulley to help it squeeze through the small gap between the dampener and fan pulley. The new pulley is also marked with TDC from the factory and it appears the 12 o'clock position is where it needs to be. When the fan and shroud are put back on I will see how easy the belt comes off and on.



Godspeed,

Trent



Trent,

That is EXCELLENT news.

Thank you so much for confirming what others (like me :-laf:-laf) have only talked about !!



I am curious, from where did you get your 6. 7 damper and pulley from??

Were they a good deal??



Thanks again.
 
I also swapped, and just as I figured, the 6. 7 damper and pulley works just fine on the 5. 9.



The pics will be back, probably end up paying to upgrade since every picture I've ever posted from photobucket is now deactivated. :mad:
 
Bought them from Scheids, price seemed to be what others have posted for these parts.

Good thing the new one fit as I dropped the old one taking it off...

Real curious to drive it and see how things change.

Godspeed,
Trent
 
Bought them from Scheids, price seemed to be what others have posted for these parts.



Real curious to drive it and see how things change.



Godspeed,

Trent



Very good, DO let us know what, if any, differences you detect and experience.



Also curious if you know how much the new damper weighs??
 
I did weigh both dampers on an electronic shipping scale. Old damper with tone ring = 16. 6 lbs, new damper has integrated tone ring = 27. 7 lbs.

Should be back on the road this week and will get back with a report.

Godspeed,
Trent
 
This is great news. I've been dreading the idea of a belt failure with my FD.

Does anyone have a Cummins P/N for the 6. 7 pulley?



mwilson provided in another thread--



Damper is Cummins #4933224

Fan Pulley Cummins #4930580



And VMcKenzie let us know that



There is ALSO a dowel pin that you can get for $1. 53

Dowel Pin# 3946495



AND if you want 4 new bolts for $1. 23 each

Mounting Bolts #4937760



Let us know where you get the best price.

I am thinking of asking Genos to carry the parts.
 
This is great news. I thank you blacksheepdiesel for taking the time, in the middle of your rebuild, for helping to fill in another piece of this puzzle. :)



I know this is a long shot, but, is there any one out there that can place a 5. 9 crank with the 6. 7 damper on a balancer and see if there are any critical R. P. M. issues that the 6. 7 HB can't handle on the 5. 9 crank? Is it possible that the 5. 9 engine, with the 6. 7 HB, can be checked for any harmonic issues on an engine dino?

'strokeThis_'07, are you going to use a 6. 7 damper on you '07 truck? I also would like to hear feed back on the long term driveability of this setup. Oo.
 
This is great news. I've been dreading the idea of a belt failure with my FD.

Does anyone have a Cummins P/N for the 6. 7 pulley?



I get what you are wanting to do now, use the 6. 7 fan pulley with your Fluidamper. It might help in changing the belt but then again it might not. The 6. 7 damper has a bevel on the back side of the part closest to the radiator, without it I am positive the belt would not come off. Hate it I can't help you more with your particular issue.



Godspeed,

Trent
 
Thanks Trent. The pulley can't be all that expensive so if I ever have to pull the fan I'll just go ahead and replace the pulley. It does seem like it would work out well since the FD is smaller than the 6. 7 HB.
 
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