4104 Radiator Shutter Air Filter Fluid

[gus]

Does anyone know what "Special  shutter fluid from Kysor Heater Corp." is in modern fluids? I tried the net and spent about an hour chasing around after the Kysor Co until I finally gave up.

I've been bragging for the last two years about how great my radiator shutter works and now it has turned around on me!!

It used to hold between 170* - 185* consistently, then this summer it has decided to move up to 190* - 200*; not good. I turned it off during the summer so it ran 170* - !80* until the weather cooled and now it struggles to maintain 165* - 170*.

I've readjusted the radiator thermostat but I don't really think that is the problem since it so abruptly changed on me. I do suspect that there is no more fluid in the filter which is supposed to lube the shutter thermostat needle valve and the shutter air cyl.

Don't tell me it is the thermostats because I've already been through that drill!!

I suspect it is about the same as Dextron and will use it if I can't otherwise get better information.

I know there are few of them working anymore but I can testify that it is a great system when it is working right, especially for quick warmup.

Has anyone else solved this problem? Thanks in advance.

[Ednj]

I put pneumatic lube/cleaner in it.

[gus]

Ed,

I presume you mean the red stuff that goes into air tools?

Thanks, I never would have thought of that!!

[gus]

I was able to adjust the radiator shutter thermostat so now the temp runs between 182 - 188* so I will turn it down a bit more and have it just where I want it.

It is a simple adjustment but hard to reach. It changes the tension on the spring that keeps the thermostat air valve from closing off the air so the shutters open.

[buswarrior]

The lube comes in a blue quart can, still available, and used here in Big Transit on the remaining GM New Looks..

I'll see if I can find the source.

Yes, for a colder weather busnut, functioning shutters are lovely.

If the dampers in your MCI are failing, pull the pins on the pistons and leave the doors open, and leave the shutters to keep working, still does a good job for busnut use.

happy coaching!
buswarrior

[gus]

BW,

Thanks.

The good thing about GMs is that all you have to do is shut off the air to keep the shutters open.