Overheating :( - Page 2

27matt · 28th September 2018, 17:20

Quote:

Originally Posted by SD1too

Just to check Matt, you haven’t got a conventional thermostat and a PRT fitted at the same time have you?

Simon

No, well I not that I fitted anyway, just bad grammar!

I changed the PRT this morning, idled on the drive for a while to check it got warm and cooled down again, I then went for a drive for about 8 miles with no major problems. Old one doesn't look damaged, but difficult to tell what's going on in there!

Seems to hold at about 88C which I think is about right?

My only concern, I was running diagnostics whilst on the drive and the ecu never requested the low speed fan. The fan stayed off until we got to 104 then the high speed came in and went off again when back in the mid nineties. The slow speed definitely works as it comes in with the demister.

It shouldn't have caused the problems I've had, but it's interesting....

I'll check levels and go for a spin later tonight.

Oh, it was also a right pain to try and fill and bleed the system, never had that problem on a k series before.

SD1too · 28th September 2018, 18:39

Quote:

Originally Posted by 27matt

The fan stayed off until we got to 104 then the high speed came in and went off again when back in the mid nineties.

Those are the correct temperatures for the slow speed Matt; on at 104 and off at 98 degrees. The slow speed can sound very noisy on 2 speed systems.

Quote:

Oh, it was also a right pain to try and fill and bleed the system ...

Did you follow the MGR official procedure? If so maybe you have an air lock and that’s the cause of your overheating problem.

Simon

27matt · 28th September 2018, 19:50

Quote:

Originally Posted by SD1too

Those are the correct temperatures for the slow speed Matt; on at 104 and off at 98 degrees. The slow speed can sound very noisy on 2 speed systems.

Did you follow the MGR official procedure? If so maybe you have an air lock and that’s the cause of your overheating problem.

Simon

Good news on the fans, I saw a thread elsewhere that they were the fast speed temps!

Yes, it's all bled correctly, it just didn't want to take any coolant.

I can't see that there would have been an airlock, I've not touched the system for a couple of years and it's been faultless.

rockerbox · 28th September 2018, 20:08

I'm probably well off the mark, but..., I did have similar with my K8 and found the 'jiggle' valve and its small hose to the header tank needed sorting, new hose and intake manifold clean out.

SD1too · 28th September 2018, 21:28

Quote:

Originally Posted by 27matt

... it just didn't want to take any coolant.

Can you explain what happened then Matt as you added coolant to the expansion tank with the bleed screw removed?

Simon

27matt · 29th September 2018, 20:50

I took it out for another drive this morning, through town and the up the motorway a junction, no problems so seemingly all Ok!

Quote:

Originally Posted by rockerbox

I'm probably well off the mark, but..., I did have similar with my K8 and found the 'jiggle' valve and its small hose to the header tank needed sorting, new hose and intake manifold clean out.

That has crossed my mind, presumably if the IMG was leaking, then air could possibly get into the system? Either way, I might change the IMG and check the jiggle valve when I have time.

Quote:

Originally Posted by SD1too

Can you explain what happened then Matt as you added coolant to the expansion tank with the bleed screw removed?

Simon

Thinking about it, I did have the front on axle stands which would have raised the header tank in comparison to the bleed screw. It did go in, just very very slow to drain.

Quote:

Originally Posted by grout20

Hi Matt,

Sounds like the thermostat may have jammed shut .... why it would do that whilst happily driving along I dunno.....

Are compressions ok?

If you could use another pair of hands give me a shout.... I'm in Stevenage.

Good luck

John

Thanks John - a good battery charge sorted the issue, probably just low from listening to the radio whilst waiting for recovery, and then probably flooding it!

27matt · 27th October 2018, 17:29

I think I've done about 700 miles since switching the thermostats over, no further problems

I'm still going to replace the IMG at some point just in case there is an air leak there, but everything seems fine at the moment.

27th October 2018, 17:29	#17
27matt Regular poster Rover 75 Saloon Join Date: Apr 2013 Location: Stevenage Posts: 68 Thanks: 5 Thanked 9 Times in 7 Posts	I think I've done about 700 miles since switching the thermostats over, no further problems I'm still going to replace the IMG at some point just in case there is an air leak there, but everything seems fine at the moment. __________________ 2006 Rover 75 Contemporary SE 1.8T 1998 Rover 216 Coupe 1986 Mini 998ish cc

28th September 2018, 20:08	#14
rockerbox Avid contributor MG ZT/T Join Date: Dec 2015 Location: Thurrock Posts: 244 Thanks: 37 Thanked 39 Times in 34 Posts	I'm probably well off the mark, but..., I did have similar with my K8 and found the 'jiggle' valve and its small hose to the header tank needed sorting, new hose and intake manifold clean out.