Overheat even though all new??

My disco recently had the head done, skimmed and new three hole head gasket. Also had all new hoses, ejector pump and thermostat.

I have slowly filled her up using a funnel on the thermostat housing and I keep the top heater hose off to let all the air out to avoid airlocks.

She's usually fine for a day or two then she'll spike on the temp gauge, although she does not seem to be running hot and the engine performs no different??

Any ideas?

I'm at a wits end now as my Rangie is giving me grief too and I might just ebay the pair of em.

Jon

Could try bunging in a new temp sender?

I'll try that fella!

Only thing that hasn't been renewed lol!

I'll let you know.

Jon

best way to fill is to take out the resovoir, hold it a couple feet above the bonnet, undo the bleed valve on the top hose but leave the top hose connected, fill up till you get a stead flow of coolentcoming out the bleeder valve, fill resovoir then to the cold water mark.. do up bleed valve, replace resovoir, run engine for a bit on idle then recheck levels..

Does it overheat when at a standstill or when moving or both?

Sounds a good way to do it, noticed before that the resovoir fills up to the top.

Usually the needle seems to rise very quickly to the red mark, if I stop it drops immediatly. Never done it while stood still.

Can the ejector pump be eliminated in any way? I have been told they are bad news, although not before I bought the Disco lol!

Not seen any leaks from the matrix, radiator or any gaskets, the P gasket and water pump are new.

The heaters seem to remain warm/hot too, I just want to be able to 'trust' it to take me anywhere without being paranoid about something going wrong. I am fitting a decat and extended brake hoses tomorrow, then she'll be waxoyled as the under side is in great nick. I'll try to refill and see what happens.

Jon

Jezath said:

best way to fill is to take out the resovoir, hold it a couple feet above the bonnet, undo the bleed valve on the top hose but leave the top hose connected, fill up till you get a stead flow of coolentcoming out the bleeder valve, fill resovoir then to the cold water mark.. do up bleed valve, replace resovoir, run engine for a bit on idle then recheck levels..

Does it overheat when at a standstill or when moving or both?

Click to expand...

that's the way to do it, otherwise it's difficult not to get an air lock.

Just a thought, does it matter if the ejector pump pipes to the top of the rad and the expansion tank are swapped over?

I don't think I have but could they be the wrong way round?

I reckon it might just be an airlock, could it be trapping the air near the temp sensor to make it spike like that?

Jon

well, while your at it, replace them plastic bungs with brass ones if you havent already... you can use simple plumbing fittings from B&Q with the correct threads

I have brass ones fella

Will grab a temp sensor and bung it in while she's empty too.

Jon

Yogi Bear said:

I have brass ones fella

Will grab a temp sensor and bung it in while she's empty too.

Jon

Click to expand...

i wouldnt bother with with a new sensor or dropping the coolant untill you've tried the elevated expansion bottle fill thing. take out the top bung and fill via the expansion tank , dismounted and lifted as high as she's go, see how it goes, then fit a new sensor.

Right o matey, I'll keep you posted.

Jon

Right o!

Filled it like you said, loads of air and bubbles came out the stat housing lol! bolted the tank back on and filled to the seam line.

Took her out, no probs, nice hot heaters and all that.

On the way back the temp went sky high on the first hill (lots of them round here) and the heaters went cold, but got her back to the house. Jumped out to find water pi55ing out of the tank cap (which is new too).

Temp dropped as soon as I stopped. Any ideas?

Jon

get the comp tested, although you have done the head , gasket and all, doesnt mean to say that its not at fault again, had water blowing past my expansion tank cap, and that was the start of it, did you replace thermostat too..

I know its not what you want to hear, but do get it checked....

One of the great things about this forum is the great tips that are given. I copy them, keep them in a folder and hope I never have to use them LOL !!