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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: John Z on July 21, 2015, 02:17:12 PM

Title: Desperately need fan hub for 4104 6-71
Post by: John Z on July 21, 2015, 02:17:12 PM
I am looking for a fan hub (part# 2137142) for a 4104, 6-71. Mine is about to let go, and I don't dare drive it.

Luke doesn't have one.

I know its been years since these were made. What are you doing if a replacement can't be found?
Title: Re: Desperately need fan hub for 4104 6-71
Post by: gg04 on July 21, 2015, 08:03:43 PM
I welded mine  checked balance on a lathe 15years ago.. People on this and other boards said it wouldn't work vibration would break crank etc. What I did... By all I knew it's just a fan hub not a harmonic balancer.  Still working fine on mine..rdw
Title: Re: Desperately need fan hub for 4104 6-71
Post by: John Z on July 22, 2015, 08:39:50 AM
Thank you for responding. Yeah, I had to wonder when I read the hub was to isolate the fan vibrations from damaging the crank? Really? The 6-71 has that weak of a crank?
Title: Re: Desperately need fan hub for 4104 6-71
Post by: gg04 on July 22, 2015, 09:30:54 AM
I did  check balance and true' ness of crank plane and hub face.  Original fan had exploded so replaced it with off road pusher fan from flex rite..rdw
Title: Re: Desperately need fan hub for 4104 6-71
Post by: gg04 on July 22, 2015, 09:38:26 AM
DUhhhh..flex-a- lite... senior moment.rdw
Title: Re: Desperately need fan hub for 4104 6-71
Post by: chessie4905 on July 23, 2015, 04:02:50 AM
   Maybe you could check the old look city bus forums. Also the old look models had a torus fan on many models. Fits on inline . BTW,the harmonic balancer is mounted behind the fan hub next to engine.
  I would have a machine shop weld and true/ balance it and install a fibreglass flexible fan of proper diameter and reverse rotation. One of the hd otr cooling fan compianies offer the model you need. I wouldn't use an oem fan after welding hub though.

http://www.fanclutch.com/ (http://www.fanclutch.com/)
Title: Re: Desperately need fan hub for 4104 6-71
Post by: John Z on July 23, 2015, 11:26:43 AM
Thanks guys. That fiberglass fan sounds like it might work with the hub made solid. I will chk out their website.
Title: Re: Desperately need fan hub for 4104 6-71
Post by: gg04 on July 23, 2015, 12:26:35 PM
I've' seen a half dozen or so of the high dollar replacement fans self destruct..never saw a flex-a-lite do so. rdw
Title: Re: Desperately need fan hub for 4104 6-71
Post by: John Z on July 23, 2015, 12:47:13 PM
That's good info on the flex-a-lite fans, thanks. Dec - May, I see we are neighbors. By Texas standards anyway. I'm in Mercedes, south of you.
Title: Re: Desperately need fan hub for 4104 6-71
Post by: gg04 on July 23, 2015, 04:34:33 PM
Its a small world. Gone north for the summer....  Got to MS then had to have bypass surgery...No racing for me this year...not sure yet if will get to drive bus till feb. rdw
Title: Re: Desperately need fan hub for 4104 6-71
Post by: John Z on July 29, 2015, 09:46:05 AM
I haven't had any luck finding replacement hub. Not sure I'd spend that much money too put in an old part anyway.

Just got off phone with Flex-a-rite tech. I was concerned that their flex fans flatten out to save power when going at high speeds and you don't need as much cooling (if your radiator is out front). Not the case with our buses. I wish I had asked at what rpm do they flatten?

Besides, the largest flex fan they make is 19". Quite smaller that the 26" blade on my bus.

He said they could make a blade that big of nylon, 250 - 300.00. But he told me he has seen them come back in a year, all busted up, when bolted direct to the crank. I know he's speaking in general, and CYA terms, but still.

So I'm still looking for input, before I proceed. RDW, which fan are you using? How many miles have you put on it? Does it do a good job of cooling?

I don't have mine apart yet so I can't visualize the welding your talking about. Do you have any pcs?

I appreciate any and all input.
Title: Re: Desperately need fan hub for 4104 6-71
Post by: Scott Crosby on July 29, 2015, 10:34:40 AM
Here's one for $1550 but it comes with an engine :)

http://m.ebay.com/itm/671-Detroit-Diesel-Engine-Left-Handed-for-Bus-or-Boat-motor-/161762486868?nav=SEARCH (http://m.ebay.com/itm/671-Detroit-Diesel-Engine-Left-Handed-for-Bus-or-Boat-motor-/161762486868?nav=SEARCH)
Title: Re: Desperately need fan hub for 4104 6-71
Post by: luvrbus on July 29, 2015, 10:43:48 AM
If you start changing too much on the front you will need to change the 600 buck + vibration damper or you will be playing with fire it has a memory once it has been ran on a engine 
Title: Re: Desperately need fan hub for 4104 6-71
Post by: John Z on July 29, 2015, 10:45:05 AM
My friends recently bought a converted 4104 for less money; and they drove it home!
Title: Re: Desperately need fan hub for 4104 6-71
Post by: gg04 on July 29, 2015, 11:53:53 AM
You have to call flex-a-lite tech support and ask for a 28"pusher fan.I don't remember model #. They will need bolt pattern and hub pilot size.  14 years and over 80000 miles still works perfect.  Took some simple mods and rebuilt my shroud. Only changes pitch above 2800rpm. Has worked for me. Tried twice with replacement fans from bus parts dealers.... both were higher dollar and neither worth a s.....rdw