Cooling Fan Question

[Rwnielsen]

Is this related to the fan? My fan doesn't appear to be switching on when the motor warms up. If so, how do I bypass/check it? It's a 1998 12v, 5.9

[Rwnielsen]

I've been snooping around and it seems that my fan could be entirely mechanical?

[HamSkoolie]

Cant help you but I'll be watching the thread as I'm not sure about mine either. It appears to be a mechanical clutch but in snooping around inside the engine compartment I spotted and electrical connector that now has me wondering.

[PorchDog]

In the Dodge Pickups that had the 12 valve-- the fan is strictly thermostatically controlled. No electrical connection. I have a 1996 and a 1998 12 valve pickup--no wires to either fan clutch. But you can hear when they turn on and off.

[Rwnielsen]

Originally Posted by PorchDog

In the Dodge Pickups that had the 12 valve-- the fan is strictly thermostatically controlled. No electrical connection. I have a 1996 and a 1998 12 valve pickup--no wires to either fan clutch. But you can hear when they turn on and off.

I think you're right about I UT my bus as well. I searched around last night and found fan clutches for around $200 new and they were thermostatic...no wiring at all. Apparently, when they fail, they're either on all the time or dont

[Rwnielsen]

Originally Posted by PorchDog

In the Dodge Pickups that had the 12 valve-- the fan is strictly thermostatically controlled. No electrical connection. I have a 1996 and a 1998 12 valve pickup--no wires to either fan clutch. But you can hear when they turn on and off.

I think you're right about it in my bus as well. I searched around last night and found fan clutches for around $200 new and they were thermostatic...no wiring at all. Apparently, when they fail, they're either on all the time or don't spin at all. I need to pull the radiator for other maintenance and I may as well swap that out too.

[Booyah45828]

Take a picture of your clutch and we should be able to tell what type it is.

[BamaBus]

On my bus the brass sensor in the middle of the picture is part #8036216 which is 172 NC and 187 NO. I also have a radiator shutter so this part may be dual purpose.
If you look at the sticker on the radiator it says that the fan may start while engine is running which may indicate an electric clutch.
Your fan blade is the same as mine which spins freely like the fan on a Cat C7 which is electric. Also I compared it to a '92 5.9 where the fan will not spin at all.

[Rwnielsen]

I want to change the belt, address the dowel pin issue, flush the radiator and put in a new front main seal. That whole fan assembly will be right in the open and easy to work on. This bus only has 64k on it but it sat in a warehouse for almost 18 years. Lots of things need attention and a little TLC.

[BamaBus]

Originally Posted by Rwnielsen

I want to change the belt, address the dowel pin issue, flush the radiator and put in a new front main seal. That whole fan assembly will be right in the open and easy to work on. This bus only has 64k on it but it sat in a warehouse for almost 18 years. Lots of things need attention and a little TLC.

I do hope that you document every boring detail in a new thread! From the picture it looks new compared to my '98 BB with over 200,000 miles.

[Rwnielsen]

Originally Posted by BamaBus

I do hope that you document every boring detail in a new thread! From the picture it looks new compared to my '98 BB with over 200,000 miles.

It looks like new underneath too. It makes it easier to understand what things are that I'm not familiar with. Mostly just dust from a where I have it parked. I'll try to document as I go but sometimes I get involved and forget.

[Dbacks2k4]

Originally Posted by BamaBus

I do hope that you document every boring detail in a new thread!

Agreed!

I had a 12v 5.9 Cummins in an old party bus a few years back. That bus is long gone... rust... but I still follow a lot of mechanical threads. I usually learn something new on each one even if it doesn't apply directly to my rig.

There are so many resources on threads and youtube of conversions that focus on carpentry and utilities. The internet definitely needs more bus mechanical and drive train content beyond "what engine should I buy" - although too many people struggle with even that.

If there was less heavily edited and selective posed glamor photos on Instagram, and more emphasis on maintaining a former commercial vehicle, I think we'd see so many fewer forum and FB posts starting with "Help! My bus won't start!"

I've been documenting my dt466e engine work on my YouTube channel for my build. My intro video titled 'I bought a bus' I posted about a month ago has about 300 views. Every mechanical themed video in about the same time frame has an average of 5 views. Speaks volumes.

I'm not a mechanic by any means, but my mechanic friend has taught me a lot about exactly how my engine works, what common issues are, how to troubleshoot, and how to do basic repairs and prevent maintenance. Combined with a few good threads and videos it's amazing what even a computer nerd like me can pick up and do.

Cheers,
Kevin

[turf]

on my '93, that's the location for the thermostat for the fan clutch.

my tstat is a bit smaller, with 2 wires. one coming from the battery, and leaving to the fan clutch. its a switch that is on at 210, off at 200, iirc.

my '93 uses an electric horton fan clutch. its a universal one, but pricey.

good luck!

[Rwnielsen]

This is an old post of mine where I may have included some erroneous info.
On my 1998, 12v, 5.9, according to the driver's manual, has a 12 volt fan clutch. This is controlled by a grounding sensor which closes at 205°. There's a very good possibility that I never let it get that hot when I was checking it. I'm going on a 120 mile joyride in 2 weeks and I'll check it then.