Hitachi ex30 minidigger overheating and stopping

daesal

Ex30 7 overheating within about 30min of running especially of I'm tracking in boggy ground.and there's a lot of boggy ground at the min. The thermostat was changed about a year ago and the machine doesn't lose water.except as it's coming up to the red and the water bubbles out the expansion tank.There was someone else useing it before and im not sure what they were doing to it. yesterday the machine was right underpowered and just quietly stopped .it wasn't under muxh presdure.just shifting a bit of 2" around the track. I left it cool down and it starts again grand but I don't want t put any more stress on it until I work out the problem.Kubota engine in ex30 hitachi. The water coming out was brown but not oily.so far can't see any evidence of water in the oil on so it's left me a bit stumped.any ideas?

Jack the Stripper

Eliminate that the water pump is ok first but sounds like head issue. Gasket or cracked head. Does it take a lot of swinging to start?

r4110

defiantly check that the water pump is circulating the water. could be a blocked pipe also check that the radiator isnt blocked or the fins aren't clogged

mythos110

An obvious one, but check that your fan belt hasn't snapped

Testacalda

Had a teleporter than was running hot a few years back due to a blocked air filter (blocked with dust from working in a gravel yard), believe it or not. Sounds odd but it can be a factor

Jack the Stripper

Op said it's boiling, water brown so rad prob blocked too. Maintaince must be poor as he said he put new thermostat last year. New coolant must not have been used.

daesal

What's the best way to check water pump? will get on that

Nekarsulm

The water pump.
Had this problem with a John Deere 3140 tractor.
Deere used a water pump with a plastic impellor for a while, but these plastic impellor's eventually loosened on the metal pump shaft, and stopped circulating the water.
I had already removed the thermostat, in case it was faulty.
Deere mechanic advised me to start the tractor and remove the rad. cap to see if the coolant is moving across the header tank. Spit in and if it remains stationary, your pump isn't circulating.
This only works if the thermostat is already removed.

The thermostat.
Just because you fitted a new thermostat, doesn't mean it's not stuck closed, or failed. Try taking it out and see if the problem goes away.

daesal

What's the best way to check water pump? will get on that

Jack the Stripper

Did you not read Nekarsulm post? Good advice there.

daesal

Jack the Stripper wrote: »

Did you not read Nekarsulm post? Good advice there.

I did yes thanks.for some reason I had a double post about how to check pump. My reply to Nekarsulm was between the double post. Good info in there

daesal

Just noticed my reply isn't there at all! Thats what happens when you post quick from the garage! Thanks Nek I will get on to that when I'm.back with the machine.

daesal

Its a bit late for reply but just in case anyone else has the same problem I thought I would update. After checking everything else it came down to the head. I got the head changed and new radiator. Machine runs great now with no over heating.