ISM Fan Belt Upgrade Kit

[rebelsbeach]

I wish you good fortune with your efforts...The black paint on my teflon guard is all worn off with just one trip under it's belt....pun intended!!
From Virginia to Florida is about as flat as you can get so no jake, must've been the high speed fan squealing in that does that belt in.

I run 70MPH on the Interstate....gotta make them miles!!

[Lug_Nut]

Bob, I would think given the reduced belt clearance with the guard installed, that it may touch during down shifts. Any time the engine increases speed quickly the fan drive has to follow, engaged or not, which will cause a breif tightening of the top belt run given the rotation direction which in turn causes a breif slack at the bottom belt run.

Peter

[Road Pilot]

The very latest fan drive assembly doesn't have a bolt. They've totally redesigned it to include a tapered spindle with an integral 3/4" (approx) shaft that has a hole for a cotter pin. The fan itself has a matching tapered receptacle. The fan goes over the shaft and a castelated nut (with a cotter pin) tightens the fan down. The bearing surface is now the 3" long surface that tapers from approx. 1" to 1 1/2 inches.

The old system used a bolt that according to a Cummins tech was essentially the same length as the bushing plus shaft i.e. too long. It bottomed out first so the bearing surface was just the end of a 1/4" bolt. No wonder they fell apart.

[rebelsbeach]

I think I'm going to hire Peter and fire Spartan....

Just off the phone with Spartan and as Peter mentions, the teflon guard is meant to be the "sacrifical lamb" for the belt slap and the "wearing off" of the paint is in fact expected...

I was again advised by someone higher than Chris Friar NOT to deprogram the ECM....

Let the good times roll...I will DEFINITELY continue this discussion at the Tampa show.

[rebelsbeach]

Indirectly had a message from the Spartan engineers....The ECM is programmed as such in order that the ECM kicks the fan in to keep the heat off the tranny...I was told there "could" be an issue with the ECM deprogram, IF...(yes Peter,a BIG if), the tranny was to overheat and fail...The fan is supposed to kick in and aid the tranny in stopping...
The engineer said that in the "perfect storm" scenario where there was a long grade and an excess build up of heat in the tranny, if in fact a failure occurred with the coach, Allison would have the recourse to come back on the coach owner...

Is this likely? I'm sure the answer would be no, but as the engineer related indirectly to me, the ECM was programmed as such per given parameters at the time of development...

I was ALSO told again the teflon coated piece is the sacrifical lamb for the belt, in order that the belt stay off the frame bracket.

I also learned firsthand of the fan hub "fix" that DocMark spoke of is the "latest and greatest" idea.....

[Lug_Nut]

Well the perfect storm is an if senario only. Killing the belt is reality. Until they come up with a better design I'ld prefer to keep rolling, which means no Jake activation of the fan drive.
Now, I'm having a problem with the engineering saying an over heat may occurr on the decellating tranny with the Jake. The engine is turning at 2000/2100 RPM with zero thottle postion. Isn't the engine going to help in heat transfer, considering it's compression heat only not fuel fired?
Also I would like to look into the fact that may be the fan controller is already programmed to engage the fan if the transmission starts to overheat. There are five things that trigger the fan to lock up. One is engine reaching 203/205, another is the ECM with Jake, there are three more. What do you want to bet that tranny heat is one of the five. If that were the case it kind of cancels out the deprogramming theory and the prefect storm.

[Lug_Nut]

Just thinking some more about this. The tranny also could start to get hot climbing a long steep grade too. The engine may not be that hot as the RPM may be high and coolant circulation at full flow. So what happens then? The fan is probably engaged by the controller to cool the tranny. If that is true it will also do the same for decending. I'm really having a problem understanding their comments. Nobody mentioned this before. Are they grabbing at straws?
Bob, can you give me a name in Spartan engineering. I would like to follow up on this when I return from Outdoor in Port St. Lucie on Wednesday.
And yes, my fan ran great from RB to here.

Peter

[Lug_Nut]

Oh, I just re-read your post Bob. May be Allison is who I should talk to. You stated that Allison may go back on the owner. Therefore this is an Allison requirement?

[rebelsbeach]

Peter, when I spoke with Chris Friar this morning in depth about this,I asked him to call Charlote and get me some answers..He called and spoke to engineering and called me back late this afternoon with the response from Engineering.....Chris Friar's cell number is 517-231-1261...I'm not sure whether or not there's a "public" access point to Engineering,but it'd certainly be worth a call.

[Lug_Nut]

I'm not sure of any info from one person in regards to Spartan. When I arrived at Newmar from out west with a badly gouged fan belt I asked Chris Friar why the Jake would bring in the fan assembly also. He claimed it did not, that the fan had no relation to the Jake. Cherrie, my wife heard it too. I walked out into the shop and spoke with Scott and Randy about it. Randy merely said it does, Chris is wrong.
So...... not everybody knows everything.

Peter

[rebelsbeach]

Peter, knowing your "history" with Chris,read my post again please....I specifically asked Chris to contact the plant in Charlotte and get me an answer from the engineers...I believe he did in fact call Spartan Chassis in Charlotte,MI and I would encourage you to call him and try and get to the engineers....
With your knowledge and experience I believe you could carry on an intelligent conversation with the engineers,it'd be a waste of time for me to ask to speak to the engineers as I could not...

[rebelsbeach]

Here is the text of an email I received from Chris Friar today....

Allison's Application Engineer does not approve disabling the fan on with engine braking. All of Allison's installation testing was done with the fan on with engine braking parameter enabled. It should be left enabled, as engineered and tested, to avoid Allison warranty concerns if an issue ever arises related to trans. overheating.

M. Chris Friar
Spartan Chassis
Customer Relations Manager
Northern Indiana
517 231 1261
cfriar@spartanmotors.com

[Road Pilot]

Bob,

I assume the ecm stores various parmeters like transmission temp, engine temp. etc. I know our engine temp went through the roof when our fan fell off. I assume there was a correspnding rise in tranny temp. In fact as I nursed the rig from Port St Lucie to Tampa, I had the dash electronic readout on tranny temp since there wasn't an engine temp electronic readout. It compare dalmost directly to engine temp.

The point is that our coach has overheated several times with everything as delivered from the factory. A read out from the ecm should show that. But it has never overheated from having the fan disabled during high jake. When we go out west I'll record some data, of tranny temp going downhill with high jake, and share it with everyone. My bet is the tranny temp is higher going up the hill then down the hill.

Bob, If Newmar/Spartan/Cummins/Allison were so fastidious qualifying the engine/transmission why in **** are so many of these things dying???

[rebelsbeach]

Dick, please don't shoot the messenger...