[Nebster]

In the process of having lots of exciting issues with my genset, I've done some reading and concluded that I ought to be able to swap the squirrel cage fan with a fancier/quieter one.

First, I'd like one that is a sealed unit, because my current one is dying after ingesting a lot of dust.

Second, it appears that the belt-driven approach reduces noise considerably. I'm not really sure why that is, but it seems to be gospel.

Third, and probably most important, the stock (Powertech) fan runs at full bore no matter. But, a lot of the time, I don't believe we need nearly those 2200cfm through that radiator. Cool days, cooler nights, etc... should be able to run at a much lower speed. So I think I want to try to find a variable speed fan and a thermostatic controller. I am going to start by having a look at what the Prevost converters are using.

I'll update this thread as I make progress (or not).

[bestgenman]

Yeah, I certainly would be interested in your results.  I had no idea the belt driven fans were quieter than direct mount squirrel cage.

Electronics are moving so fast these days at which I wouldn't be surprised if someone is using thermistor driven fans.  Variable frequency drives are very cheap nowadays which would work with a totally enclosed fan cooled motor as used on belt drive fans.  The VFD will accept a 4-20 mil or a 0-10V signal that would typically be fed from a thermocouple.  That method has been in play for years.

Galco electronics has low priced single phase VFD's.  Dwyer has thermocouples and interfaces to get you to the input level of the VFD,  https://www.dwyer-inst.com/Product/Temperature/Sensors/    &   https://www.dwyer-inst.com/Product/Tempe.../Series651

Hope this helps...........

[Nebster]

Thanks, Gordon, you sound like you know a lot more about this than I do!

It is a little lower down my priority list in the huge backlog of mods for this bus, but I do intend to get started researching options right away.  

I didn't realize I could just buy these standard linearizers and put the output almost straight to a VFD, but it makes sense of course.  Being more of a software guy, I was figuring I'd end up rigging up a little microcontroller from scratch, but your links point to something that will probably be more reliable and simpler.

There is already a thermocouple or thermistor inline somewhere, because I can see the water temperature on a readout above the dash.  And it is distinct from the high temperature sender that shuts down the engine, because I had to remove that broken sender last week and run the genset without it for a while.  (As it happens, something else failed 100 hours later, and I managed to boil all of the water out of the system, but it appears the engine survived...  sigh.  I had to limp 1000 miles home running off inverter, engine alt, and whatever power poles I could find along the way.)

Okay, stand by.  :-)

[encantotom]

what is it with these engineers that want to make things better? oh yea, that is me too....

tom