Engine fan

[Moose]

Does it spin all the time or is it on a clutch controlled by engine temp

[cadillackid]

Originally Posted by Moose

Does it spin all the time or is it on a clutch controlled by engine temp

most all the busses since the late 80s have clutch fans.. some are viscous type clutches where the fan spins a minimum (usually 300-400 RPM) all the time.. and then slowly engages via a mechanical thermal coil on the front of the clutch if the radiator heats up..

fancier busses have an electric clutch .. then fan spins very slowly all the time.. and then when the engine reaches a set temperature the fan cluch snaps-in and the fan runs full speed..

the electric or air clutches will have wires and / ir an air line going up near the fan. the viscous clutches will be aluminum or gold colored and have fins around the hub..
-Christopher

[Moose]

Mine not spinning at all any thoughts

[Robin97396]

Generally speaking, that's not good. And you're dealing with an FE. I can't see my fan clutch either.

Do you ever get the temperature up near 210? Mine takes a pretty long hill before the fan comes on.

[cadillackid]

Originally Posted by Moose

Mine not spinning at all any thoughts

it doesnt even slowly rotate when the engine is on? is the belt on the pulley? you should get a slow rotation all the time just from bearing resistance..

-Christopher

[Robin97396]

I never heard the fan in mine for months after I bought it. I had to run it to the top of a mountain before the fan finally kicked on. It hit real hard like it had been stuck and scared the carp out of me.

I've got a question about the fan clutches. Do they come on at different speeds, like low/medium/high, or just on/off? Sometimes it sounds like it's running at a lower speed, but that first time it came on with a bang.

[Brad_SwiftFur]

Originally Posted by Robin97396

I never heard the fan in mine for months after I bought it. I had to run it to the top of a mountain before the fan finally kicked on. It hit real hard like it had been stuck and scared the carp out of me.

I've got a question about the fan clutches. Do they come on at different speeds, like low/medium/high, or just on/off? Sometimes it sounds like it's running at a lower speed, but that first time it came on with a bang.

On my bus, the fan either spins lazily, or engages at full speed. It's some sort of viscous clutch, so it "spools up" and releases somewhat gradually.

On my truck (and many big trucks, for that matter) uses an electric clutch, so it kicks in quickly. Some fans will even "chirp" the belt as they engage.

I understand there are viscous fan clutches that will spin at various speeds, depending what the air temperature is (and that means the air temp going past the clutch, not the outside temp.)

[somewhereinusa]

My bus has a hydraulic motor that runs the fan. Since I can't hear it and the motor doesn't overheat I assume that it comes on. I've never actually seen it run other than at start up.

My semis all had air operated fan clutches. Fan is pretty much instant on. My first truck controlled the AC head pressure by turning the fan on and off. If that thing came on during a gear change I guarantee a missed shift.

[cadillackid]

my DRV bus has the viscous clutch .. that clutch has a Minimum speed of 300 RPM.. my red bus has the electric horton.. which Chirps the belt when it kicks in. one of my threads I chronicled the installation of it so you can see what it looks like.. I also did a youtube video of how to Clock (adjust the temp) of a viscous fan clutch..

the air driven clutches are pretty common on trucks and some busses. the air engagement is a little less harsh on the belt.. that "chirp" is hard on the belt.

ive only ever seen a hydraulic fan in a rear engine application where the fan is installed on the side of the engine bay and the engine is Longitude mounted.. the rear engine hydraulic motors are typically 2 speed so you wont hear your fan unless you engage high speed which is usually when working the engine hard.. ie climbing a hill. otherwise the fan speed runs on low and is enough to cool the engine.

-Christopher

[Robin97396]

My fan clutch seems to be working fine since that first time it came on so hard. I can't see the fan in this FE so I don't know what kind of clutch it has.

It does turn on when the coolant gets about 205 or 210, but it takes a pretty hot summer day or a very long hill to get the engine that warm. I can count the number of times my fan has turned on on one hand over the past two years.

I may not be able to see my fan clutch, but it is working. Thanks for the edification.

That brings me to another question. How do people change the fan belts on a FE?

[Mountain Gnome]

Originally Posted by Robin97396

My fan clutch seems to be working fine since that first time it came on so hard. I can't see the fan in this FE so I don't know what kind of clutch it has.

It does turn on when the coolant gets about 205 or 210, but it takes a pretty hot summer day or a very long hill to get the engine that warm. I can count the number of times my fan has turned on on one hand over the past two years.

I may not be able to see my fan clutch, but it is working. Thanks for the edification.

That brings me to another question. How do people change the fan belts on a FE?

Aloha Robin
We seem to have the same basic bus (mine is a 1999 BlueBird TCFE-1000 HandyBus, Cummings L6 motor). love this bus...

My fan also kicked in suddenly, and very loudly, while climbing mountains; very steep, high mountains; and steep uphill grades in stop-and-go (construction zone) traffic. It did not "bang," but it almost sounds like bearings are going out, with a very loud "whirl" noise. My gauge does not have actual temps, and my dash has 4 gauges-in-one, and normally it only shows fuel level; I have to press a button on the dash to see the engine temp. (BlueBird claims forcing the driver to press buttons on the dash is less distracting then showing the gauge full time. They only auto-display if there is a problem. Great! Now I "blow up" my motor overheating it without warning leaving me stranded instead of simply slowing down as I notice the heat rising. If my alternator is going weak, a battery is dying, or an improper high-current draw is creating a fire hazard, I won't notice the lowered voltage until something fails..... I think they were just being cheap...especially as the button is failing at times).

When the temp is near red, the fan comes on for maybe 1 minute, and the temp drops quick. I plan on pulling it all off and I guess I will replace the clutch unit.

To change the belt, it looks to me like the radiator needs to come out. Fun Fun Fun. However, it looked easy enough at first glance. And I guess a coolant flush would be a good thing. An International I looked at with that L6 motor had a coolant filter. Apparently the Cummings does not.

[Robin97396]

Originally Posted by Mountain Gnome

Aloha Robin
We seem to have the same basic bus (mine is a 1999 BlueBird TCFE-1000 HandyBus, Cummings L6 motor). love this bus...

My fan also kicked in suddenly, and very loudly, while climbing mountains; very steep, high mountains; and steep uphill grades in stop-and-go (construction zone) traffic. It did not "bang," but it almost sounds like bearings are going out, with a very loud "whirl" noise. My gauge does not have actual temps, and my dash has 4 gauges-in-one, and normally it only shows fuel level; I have to press a button on the dash to see the engine temp. (BlueBird claims forcing the driver to press buttons on the dash is less distracting then showing the gauge full time. They only auto-display if there is a problem. Great! Now I "blow up" my motor overheating it without warning leaving me stranded instead of simply slowing down as I notice the heat rising. If my alternator is going weak, a battery is dying, or an improper high-current draw is creating a fire hazard, I won't notice the lowered voltage until something fails..... I think they were just being cheap...especially as the button is failing at times).

When the temp is near red, the fan comes on for maybe 1 minute, and the temp drops quick. I plan on pulling it all off and I guess I will replace the clutch unit.

To change the belt, it looks to me like the radiator needs to come out. Fun Fun Fun. However, it looked easy enough at first glance. And I guess a coolant flush would be a good thing. An International I looked at with that L6 motor had a coolant filter. Apparently the Cummings does not.

We do seem to have related buses. The main difference being my '97 is all mechanical. I'm also quite happy with this model of bus. Love, love, love these flat floors.

I was afraid someone was going to tell me the radiator had to come out to see the belts and fan clutch. Thanks for confirming that nightmare. I just completed a thorough coolant system flush and new coolant mix. At this point I think I'll just buy the belts and extra hoses to carry with me, since most things are in reasonable shape.

I agree that things are simple enough to remove the radiator, but you know every job has it's add on work and costs. If you ever have the radiator our it would also be good to check on the killer dowl pin these engines are so famous for, or maybe yours isn't included in that.

My fan doesn't start with a bang anymore. It seems to be quite normal now, simply firing up when the temp gets near 210. I'm guessing that in this buses flatland life it didn't use the fan. I so rudely drove it up the mountain in a make-it or break-it scenario so I could see if it would take it. That was just a few months after I bought it. It's still rare to hear the fan come on unless I'm in the mountains. Occasionally it will come on during freeway backups on a hot day.

You know the deal, we have to assume everything needs service when we get these things. I don't trust what I haven't been able to inspect personally. There are no belt noises or anything indicating thing are wrong. I just don't like to trust a vehicle that's new to me when I'm way out in the boonies. Getting a 20k lb vehicle out of the woods would likely require a log truck or something of similar size to get back to hardtop where the towtrucks would actually pick the bus up and take it wherever. I don't want to disassemble this thing while I'm out in the woods just for a fanbelt.

I've been looking at those coolant filters lately, ever since Chris started talking about his. I guess that's a cornbinder thing. It's easy to find the spin on coolant filters but I'm not finding the inline housing for the filters to screw onto.

There is a ton of constantly flowing information on this site, most of which is good to know but doesn't apply to my vehicle about 99% of the time. Thank you for chiming in with a very similar vehicle.

Are you actually in HI?

[2kool4skool]

Our 5.9 fan engages at 202f and disengages at 197f per the Scangauge D. We have a 190f thermostat.

I replaced the belt and tensioner some time ago, pulling the rad. is not that bad but I did it via reach around. The AC belts are outboard of the serp. belt so they must come off first.

[Robin97396]

Hey Don and Mary. You guys seem to be keeping yourselves busy these days.

You have factory air?

I think I'm going to use a mirror to do an inspection with your reach around method. That belt would have to look pretty terrible to get me to pull the radiator.

[2kool4skool]

Yes, BB fac. AC X 2!


Busy, yes. next run is Skooliepalooza 2 in Ehrenburg AZ beginning 1-5-18.

[Robin97396]

That's a real thing? I've heard or Skooliepalooza a number of times but thought it was just a general name given to a gathering of skoolies.

I live such a sheltered life.

[2kool4skool]

https://www.facebook.com/events/416769698707835/

33.571468n 114.529881w

We're hosting the 2nd annual 2Kool Skoolie Campout on July 13th. near Williams AZ. http://www.skoolie.net/forums/f46/2k...-on-19388.html
https://www.facebook.com/events/119076218719460/

Yea, you need to get out more

[Robin97396]

Well, Arizona is pretty close. Just a hop, skip and jump from Lost Wages, NV.

My problem is I've got a fair amount of equipment here that I need to get rid of so it doesn't get destroyed while I'm not home. Rough neighborhood.

[Rivetboy]

Hi Robin , Moose and all. My tc 2000 pictured 1991 Cummins 5.9
To remove the belt I removed the bumper, headlite sheetmetal, hood , Hood stay, inter cooler and the radiator. Easy job and shazam, everything is right there.The fan in this bus was operated by a 190 degree thermal switch right in the top hose. Except this one was open and previously someone used the dead switch as a junction block and my fan ran all the time. I would suggest replacing the idler too. Putting a screwdriver on it and spinning it it sounded like it had rocks for bearings. To drain the radiator and pull everything off took a hour and a half and part of that was looking for something to drain coolant into. The fan clutch itself has 2 wires, one from 12v+ and the other to ground. I replaced my fan it was a bit chewed: $68.00 plus shipping.
Joe

[Robin97396]

I've kind of painted myself into a corner by using my bus as a daily driver. Of course I could perform all this work in the parts store parking lot so I don't get stuck needing parts while I'm home in the mountains.

Thanks. That doesn't look to terribly awful. Just a major PITA. I certainly agree on the idler and anything else I can nail down while I've got the engine exposed.