3CX overheat :(

[Jeremy Rowland]

Hugh, in that case you describe, did the head gasked need replacing afterwards?
S

No it would not need replacing unless the machine overheated again and that was found to be the problem, engines can overheat for all kinds of reason but I suggested that the symptoms of your machines problems sounded to me like the head gasket had gone because most of the other problems that can cause a motor to boil had been ruled out.
I think that the best course of action for you is to carry on using the machine but keep an eye on the temperature guage and if she boils again while she's under load then I would suspect that the head gasket is the problem.
You will soon find out because if it is the head gasket thats started to leak then the motor will boil again under load.

Jeremy

[McSpud]

Thanks Jeremy!
Thats the first glimmer of optimism I've heard so far! lol!!
I'll do just that, like I said, this machine could be considered being 'in retirement' and seldom does any
seriously heavy work, the only reason we have it is because I have a gammy wrist and cant make much use of a shovel.
Theres no foreman here shouting for something to get done quick either! hah!!

I'm feeling better already

I'll keep you posted...
Thanks lads,
S

[Hugh Jaleak]

As far as I know she kept working, no head gasket issues. They'll take a hell of a punishment before causing any major headaches.

[McSpud]

Hey lads,
Just had this thing out again last night, first time since I replaced the thermostat...
I was working it reasonably hard, but not abusing it....
This time, I made sure the overtemp alarm was working before I started, and it done the job fine.

Thing is, when I got it back to the yard and parked up, I could hear the coolant gurgling and bubbling inside in it.
I'm still at a loss to explain this, I know you guys said the headgasket, but this time there was no outward signs of trouble, only when I parked up and turned it off I could hear the bubbling...

Could it be possible that there's air in the system? Is there a procedure for bleeding it do any of you know?
Cheers,
S

[Jeremy Rowland]

Hi Seamus,

Whilst I am not familiar with bleeding the cooling system on a 3CX, I would suggest that you look for the highest point after the thermostat (usually the top hose),run the engine to temperature and then CAREFULLY slack off the top hose clip and insert a screw driver or suitable tool under the hose edge to permit the air to exit and the coolant to flow through. When coolant comes through and no air then the system should be fully bled.
If there is a different procedure for a 3CX then I'm sure there is a knowledable person on CMN who will be able to offer some advice.
Engines normally don't get air in the coolant system by themselves unless there is a problem.

Jeremy

[McSpud]

Hi Jeremy,
I'll try that later on so... I notice a removable plug down near the temperature switch on the water pump, I'm wondering if that could be something I could bleed from... Also, how plausable would it be for the impeller to be loose on the end of the waterpump shaft, ie, that it's not pumping?

I was thinking if I took out the thermostat and see if it still boiled / overheated, then would it be a sign that it's not pumping the water around... I don't think theres water in the top hose when I squeeze on it... Geez these cooling problems are mysterious!
Seamus

[bilco]

Hi, I'm new to this forum and only just spotted this thread. About 3 months ago I had serious boiling problems with my JCB 3cx much as described. Cutting a very long story right back to basics it was the WATER PUMP IMPELLER that was the problem, it was free spinning on its shaft. Apparently this seldom happens on original pumps but is very common on aftermarket re-cons. My machine now has a genuine JCB replacement pump and is happy as Larry. bilco

[McSpud]

Hey Bilco, thats exactly like whats happening here I'd say! I really hope it's as simple as that, I hope to dismantle it soon, I just have a few other things dismantled in the yard as well and want to get those finished first.

I'll let you know what happens!
Cheers!

[bilco]

I'd say it's 100% the pump, everything you have described is exactly the same as mine was. When you remove the pump try to get (I think its the rearmost) stud to come out rather than the nut off, on mine the pump was sliding back on the stud but wouldnt clear the frame . bilco

[lee]

hi i had a bit to do with this model is there a oil cooler in front of the radiator if so the muck gets stuck between the 2 may just need cleaning if you are realy stuck google digger doctor he will be the man to ask helped me loads of times
good luck