Coolant temp light - comes on right after startup

[mrlegoman]

I've got a Ditch Witch XT850 with a Kubota diesel 1105 engine. 1020 hours. Very recently while warming up (about 5 minutes after startup), the coolant temp light comes on. Manual simply states "check fluid level". Coolant level is fine.
Not sure where to start. Is there is a thermostat that could be stuck closed? Bad temp sensor?
The XT is a rare machine, so no help online. I downloaded a tech manual for the 1105, but it doesn't have a troubleshoot section. Friends suggested this site for help.

 

[Tooljunkie]

My first step would be an infra-red temp gun, to determine if it is actually heating up.
Next run it with rad cap off and see if
1- it purges coolant or coolant is foamy or has bubbles
2-as engine warms up does coolant flow in radiator.
3-exhaust normal, hasnt changed since problem started

 

[D2Cat]

In five minutes there can not be enough heat generated by that engine to cause damage, but as TJ said, use the infra heat sensor to shoot the upper radiator hose, the engine at the sending unit, even check the lower radiator hose. You'll end up with three different numbers.

May very well be you sending unit.

Oh, if you don't have the infra-red heat sensor you can get one at Wal-mart, Harbor Fgt, etc. for $15-$25.

 

[mrlegoman]

Thanks for the info.

Started the witch today and again after 5 minutes the light came on.

Top of the radiator measured 150
Top hose 140
Bottom hose 95

No change in fluid level in overflow tank.

Let it cool down and took cap off. Coolant color looks normal. Started engine and it did not foam. Engine shakes too much to tell if bubbles.

Currently surfing net for a new sending unit.

Found this under "senders":
http://www.powertechgenerators.com/products/05stkub05

Is there a separate oil temp unit? This one doesn't specify coolant.

Spent the last two hours searching for service/part/repair manuals for the 1105 and have not come up with anything.

 

[Daren Todd]

Are you talking get about the d1105 engine? If so, search magnum power products for there light towers, or ingersoll rand light towers. Both use the d905 and 1105 engines. They more then likely use the same sending unit to trip the relay for the engine shut down incase of over heating. All the sending unit is, is a normally open switch that closes when it reaches a certain temperature. Kubota uses a similar set up to trip the oil light on the dash.

Magnum has changed there name, can't remember what it was. But here's there tech and sales number 920-361-4442. Ask for tech support and use model number MLT3060, for the light tower. And ask for the shut down sending unit. They might ask for a serial number. If that's the case, then send me a pm, and I can get you one. I'll check the manual I have for it tomorrow and see if they list the part number in there.

 

[mrlegoman]

Great info, thanks!

So in the meantime, there is no reason I can't run the machine, right? I would assume as long as my hose and tank temps remain under 200, there is nothing else wrong.

 

[85Hokie]

Great info, thanks!

So in the meantime, there is no reason I can't run the machine, right? I would assume as long as my hose and tank temps remain under 200, there is nothing else wrong.

IF you are running it hard and for a long time - you might very well be at 200 - or even 210 coming right off the head into the top of the radiator......most cars/trucks run at about 210......when fully warmed to operating temps.

now the bottom of the radiator should be.....o ....something like 50 degrees cooler, or perhaps a little more.

 

[Daren Todd]

Coolant temp switch is part number 14099. You'll have to ask them what the thread pattern is on it. But I believe it's 3/8 bstp to verify what you need

 

[mrlegoman]

Coolant temp switch is part number 14099. You'll have to ask them what the thread pattern is on it. But I believe it's 3/8 bstp to verify what you need

Found one on ebay!
http://www.ebay.com/itm/Magnum-1409...sh=item2a5d4c7918:g:NloAAOSwstxVSUep#shpCntId

 

[Daren Todd]

Sweet even better


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