6.0 fan on OBS Results....

[7.3psd97444]

Ive heard of 2 6.0 fans on OBS's failing in the past two months. Taking out radiators.

Considering the 7.3 does NOT have any type of cooling issue, I see no point in this mod.

Not trying to start an argument, just thought ide throw that out there.

 

[Peroni]

Ive heard of 2 6.0 fans on OBS's failing in the past two months. Taking out radiators.

Interesting, can you elaborate any more on the nature of the failures?

I was able to jockey my fan shroud a little to solve a slight clearance issue. So far no problems to report.

 

[7.3psd97444]

the fans broke, and pieces scattered. IIRC.

 

[Krause]

May have been used fans that had hairline cracks in them to begin with. If they failed on a 7.3, then they were damaged somehow during the accident that caused the part out, or the removal process or something... Or else they would be failing on the 6L as well. I wouldnt recommend buying a used 6L fan when they can be had on tousley ford for 56 bucks.

 

[7.3psd97444]

May have been used fans that had hairline cracks in them to begin with. If they failed on a 7.3, then they were damaged somehow during the accident that caused the part out, or the removal process or something... Or else they would be failing on the 6L as well. I wouldnt recommend buying a used 6L fan when they can be had on tousley ford for 56 bucks.

Almost positive at least one if not both fans were new.

The common excuse ive seen in other discussions about this was what you just said. If they are failing on the 7.3 why arent they failing on the 6.0. Seems logical. Well my only guess to that would be, the 7.3 fan was designed for a 7.3. The 6.0 fan was designed for a 6.0. Could it be a simple as the different, more vibrations from the 7.3 is finding the weak link in the 6.0 fan? Ide be willing to say that the metal 7.3 fan is stronger then the plastic 6.0 one...
Just food for thought. I'll have to dig through the previos discussion I had with several others uncluding the ones that had them break, to see what else was said about why they were breaking on the 7.3.

 

[jschildm]

The 7.3 could have different frequencies that hit the natural frequency of the plastic fans making them degrade quickly. I would be a bit surprised as any diesel has plenty of vibrations, but I have seen stranger things.

 

[TyCorr]

I don't see where the 6.0 clutch is any better than the 7.3 clutch anyhow ? maybe I'm missing something, but mine works great, and I'm VERY pleased with it.

in the morning, after sitting all night, the fan will run for a bit, until the oil "Throws" out of the clutch, you can rev it up to about 1400 RPM and hear it,
(takes a bit longer if it's real cold, because the oil is also cold), but then it doesn't pull enough air to put in your hat. I can see where in the really cold country
it could be a problem, and if I lived in Michigan or someplace cold, I'd probably take the fan off for the winter if I wasn't going to tow anything.

Sounds like a jet engine! Without a load behind mine it doesnt come on very often even in the summer. My truck almost seems like the cooling system is oversized unless you are towing.

 

[7.3psd97444]

The 7.3 could have different frequencies that hit the natural frequency of the plastic fans making them degrade quickly. I would be a bit surprised as any diesel has plenty of vibrations, but I have seen stranger things.

This is my thinking, and the conclusion of the previous discussion I had. Which I still can't seem to find.

 

[cbuttre835]

Somebody measure the crank pulley dia. and water pump pulley dia. on each engine, and compare engine rated RPM and fan rated RPM (ratio of pulley diameters). Even though a 6.0 has higher rated engine RPM the fan may be "geared" down quite a bit; and thus being oversped on the 7.3.

Which would explain much better cooling, but also the failures. :shrug:

 

[Peroni]

Are the plastic SD 7.3 fans prone to failure? Wouldn't they be of the same or similar construction to the 6.0 fan?

 

[old man dave]

It could also be a case of torqued "tite enough" instead of torqued to the right spec, causing stress fractures in the plastic fan.

 

[Got4wd]

It could also be a case of torqued "tite enough" instead of torqued to the right spec, causing stress fractures in the plastic fan.

I have the 6.0 fan and the center in metal. That should rule out the over torqued bolts right?

 

[Old OutLaw]

Well, so far, I have had ZERO problems with the 6.0 fan......it cools MUCH better, and I'm very pleased.....I have been about 3,000 miles with it on so far, everywhere from sea level up to and including 8,000 feet, (ALL Towing miles), and it works fine, from zero to 3,200 rpm and everywhere in between.

I DID buy a NEW one tho, and torqued it on the hub with an actual torque wrench......

really good mod.....

 

[mxtwo50r]

Almost there....

 

[Strokersace]

I've got 30K miles on mine mostly all towing miles. Ran hard. Bought used out of a junk yard. Put it on to what I felt comfortable tightness. No torque wrench. ZERO issues.

 

[Overkill]

Are the water pump pulley sizes different between both motors? If the 6.0 pulley is larger than the 7.3 the fan may be overspinning causing the failures.

 

[Dieselfever]

The 6.0 crank pulley is larger, so yes the accessories all turn slower compared to a 7.3. I have a 6.0 engine sitting here and I'll dig around and find a 7.3 balancer and water pump pulley to measure and compare

 

[gmax228]

opcorn: subd

 

[96F350KID]

Just had one come apart on my dually tonight. Got in it real hard running a friends dually Cummins and smelled coolant and sure enough the top of the blades broke off on 3 and one piece went into the radiator. Fan was used but had no cracks in it. I think they're spinning to fast. The factory electromagnetic 6.0 clutch turns the fan off to a slow spin at WOT. The 7.3 clutch doesn't and i think its spinning too fast.

 

[Old OutLaw]

did you buy a used one, or a new one ?

haven't had a bit of trouble, but I never take it over about 3,000 rpm...