Engine running cool

[William Willard]

Originally Posted by Twomed

The info I posted was for a side rad 400 ISL. Went through this issue a few years back. No damage other than lower mileage.

Thanks for the info -- Tried to connect to the link you posted, but couldn't-- Bill Willard

[Twomed]

https://www.google.com/search?q=Hydr....com&x=28&y=12

Lots of info here.

[William Willard]

Originally Posted by Twomed

https://www.google.com/search?q=Hydr....com&x=28&y=12

Lots of info here.

If I read this correct, when you turn on the dash air, the cooling fan will start -- Bill Willard

[Mike Canter]

I don't believe that is correct. The side radiator cooling fan is controlled by engine temperature measured in the radiator. The dash AC being turned also turns on the fan to the condenser coils under the front of the MH.

[William Willard]

Thanks Mike -- Perhaps I read it wrong, or maybe their mechanical skills are on par with mine --- I don't what we were thinking, when we decided to visit Texas, Oklahoma, & Missouri in May-- Tornado Alley , Tornado Season -- Don' t make sense , does it -- I'm ready for some "Dry Heat " in AZ -- Bill Willard

[William Willard]

The first few miles of the trip, the temp reading is in the 90's ,where it has always been after warmup, then it goes back to the high 70's temp --- The fan is running at a slow speed -- I'm assuming that the thermostat is closed at start-up, & then opens at about 92, then stays open -- I know the cooling problem is probably the fan controller, but while I'm parked a few days here in Kansas City, I thought I would change the thermostat --Any of you know what thermostat the 400 ISL takes -- Any advice on changing the thermostat will be most apperciated -- All I have is the tools & desire , no ablity -- I do know where the thermostat is , & have container to drain the coolant--Bill Willard

[Mike Canter]

If the thermostat was stuck open it would probably stay around 123-130 and take forever to get there. If it was stuck shut then it would overheat. It doesn't hurt to change the thermostat. I do that every 50k miles anyhow. You should be able to watch the temperature and see it opening and closing. If you have bought the thermostat already then what temperature is marked on it?

[William Willard]

Mike -- I haven't purchased it yet -- Wasn't sure what to buy -- I looked in the Cummins manual, but didn't see what I needed -- Should have changed it when I changed the coolant-- Are the thermostats a standard size, just rated at different temps ? -- Bill

[Mike Canter]

There are a couple of numbers on a metal tag on your motor. One is the serial number and the other is a build number. If you write down those numbers and go to a Cummins dealer he can look up your engine and give you the exact replacement you require. Yes, when you change the coolant is a good time to change the thermostat. To find the closest Cummins Dealer you can call 1.800.DIESELS

[Topman]

When I was researching info on our coach before purchasing, I looked up any recalls etc. There wasn't really a recall but a "service bulletin" regarding thermostats in the Cummins engines.
You should be able to look it up online.
Iver.

[William Willard]

Thanks for all the info you've provided -- We'll be headed back to AZ soon,& I see the temps there are in the 100's, so that should warm things up -- I've done a lot of work on this coach myself, just not a thermostat -- Bill Willard

[Mike Canter]

There is another storm brewing for the High Plains area. Have a good drive home.

[William Willard]

Originally Posted by Mike Canter

There is another storm brewing for the High Plains area. Have a good drive home.

I've been watching the weather channel , & maybe I should be more concerned about keeping the shiny side up, than a cooling problem -- I see where it's 109 in Phoenix today, so that should heat the system up a bit -- Bill Willard

[Mike Canter]

Let me know how it goes