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Topic: Found air leak today, need replacement P/N (Read 623 times) previous topic - next topic

Found air leak today, need replacement P/N

My son and I tracked down an air leak - it is the thermal air valve that controls the radiator fan clutch. It is attached to the DD 6V92 curb side thermostat housing. It is leaking out the back, through the air outlet. Does anyone know the part number for this, or the recommended turn-on temperature? Thanks!

Peter and Tammy Fleming
1991 U300 GV 40 - Sold, owned for 4 years
Downsized to Roadtrek Popular 210 class B

Re: Found air leak today, need replacement P/N

Reply #1 –
[/b]The valves that I have replaced like that have a temp. stamped into the housing.
Mark Freeman 1995 grand villa, Brimson Mn
8.3 Cummins  G95 4709 40 WTBS U280 WE21

Re: Found air leak today, need replacement P/N

Reply #2 –
Wow, that didn't take long! With a little help from Mark F, it is called a Kysor Shutterstat, and looks like this:
Kysor Shutterstat
These are used a lot on trucks to control radiator fans, radiator shutters, etc. Will be back to Boyer Truck on Monday, they will probably have to pull it and read the temp rating. I can't be draining antifreeze and working on the coach on the street in front of my house... :) Thanks Mark F!
Peter and Tammy Fleming
1991 U300 GV 40 - Sold, owned for 4 years
Downsized to Roadtrek Popular 210 class B

Re: Found air leak today, need replacement P/N

Reply #3 –
Hi Peter, any luck ? Mark
Mark Freeman 1995 grand villa, Brimson Mn
8.3 Cummins  G95 4709 40 WTBS U280 WE21

Re: Found air leak today, need replacement P/N

Reply #4 –
Mark,

Yes, I found a 180F shutterstat on Ebay. Until that comes I found out that the Kysor fan clutch engages with no pressure, and is held open with pressure. This is done as a fail-safe, so if the air pressure is lost for some reason, the fan will turn on and keep your engine from overheating. So I just disconnected the air supply line and capped it temporarily. We can use the coach until I can replace the shutterstat - the fan spins all the time. I test drove it and the engine comes up to temperature just fine, maybe a little slower than when the fan is off until the shutterstat is controlling it.

This was definitely the source of the air leak, my pressure holds much better now.

Peter and Tammy Fleming
1991 U300 GV 40 - Sold, owned for 4 years
Downsized to Roadtrek Popular 210 class B

Re: Found air leak today, need replacement P/N

Reply #5 –
With the fan running all the time your fuel milage will be real bad.
91 GV U300 Unihome 40' Build 3811
6V92TA Detroit