Radiator shutters revisited

[JohnEd]

Ohhhhh!  Roberto!   "Go Fast Airplanes".  All a twitter.

[chazwood]

My mc9 was a deep south (Miami) bus, that no longer has working shudders (completely missing) or working baffles, (fixed open). On my last two trips in mild weather, the water temp never got over 150 until I put a piece of foam board in front of both radiators.....after covering about 75% of the radiator the water temp went up to 175 and the power increased noticeably. I think I'll try to get the baffles working again. I'd rather have shudders, but don't know where to find some. Anyone have some they don't want?

Thanks.

Chazwood

[buswarrior]

Hello.

From a practical perspective, it might be best to just think of the shutters/dampers as a system to speed up warm up, and to maintain engine temps under cooler operating conditions.

The degree to which there are hidden power or efficiency gains lurking in the fan system would be relative to the amount of time the shutters/dampers are actually closed while underway.

Unlike trucks and schoolies, with their radiator filled noses, there is little to no ram air effect for our rear/side mounted engine radiators (Unless your name is Hobe... or you have his rad intakes!)
All the air needs have to be drawn in by the fans, we cannot enjoy the free, long "fan-off" times of the front engined crowd.

The shutters/dampers do not stay closed for long, once the coach is in motion, and typically do not close while driving if there is any load on the engine. Those who have removed the large stock heater, and outside air intakes for the heater, will see even less shutter/damper closed time, as that is another source of engine "cooling" gone.

It is interesting to consider all the variables, but any increase in efficiency, small and likely unmeasurable, in this will be due to the motor running at the right temp, not fan-off time.

happy coaching!
buswarrior

[gus]

Fan HP is not an issue on my 671 because half the shroud is missing and even if it weren't the fan just stirs up the air, I don't think there is any serious suction while the shutters are closed.

Also, as already posted, after the engine warms up the shutters open and close pretty often.

So far it hasn't sucked any radiator core out!!

[jackhartjr]

Haven't researched this at all yet...can you still get the parts to make the shutters work...and can you still get the louvers?  And if so how many first born male children do I have to sell?
I am not sure what I have on the radiator, haven't taken the box with the broken back glass, (Do I hear Taps in the backgound playing) off of the radiator.  All of that is sitting in the rear of the bus on the floor.
Thanks in advance!
Jack

[tekebird]

if someone is interested I have a brand new Shutter assembly...think it is from a GM Transit, won;t work on an MCI, but someone with a GM.....Probably covers 80% on a 4104/4106 radiator