Over heating (maybe)

[Bob696]

I took my 200Tdi 90 (aka Daisy) down to Allisports today and had a performance intercooler fitted. Its GREAT (nearly killed myself twice on the way back to the motorway).

Got on the motorway and sat doing a steady 70 for about 15 mins when I looked at the temp guage and it was at about 90%. She normaly sits at a rock steady 60%.  I throttled back and tootled along at about 55 for another 10 mins and nothing changed. I pulled off at the next services, switched off the engine, temp guage dropped to zero, then turned the ignition back on (to stop the alarm going off) and the temp guage rose to its customery 60%. This is the bit that I dont understand, the engine was only switched off for a second.

I popped the bonnet but could see no problems. The bonnet was hot which I dont remember from before but I never had cause to check it before.  Started her up again and did the last 20 miles with no bother.

Anybody got any ideas ?

will it happen every time I cruise at 70?
Was it a sticky guage and if so what was it doing that high anyway?
some sensor somewhere screwing up?

[hobbit]

The two easy things first are the thermostat and temp sender unit, not too expensive and relatively easy to do.

I take it your rad is ok, mine unfortunately is suffering with terminal chorrosion of the cooling fins, so looks like a new rad for me

[kevinf]

dont forget the bigger inter-cooler wil restrict the air flow thru the radiator
so the radiator needs to be in a decent condition ie no corroded and folded over cooling fins in the matrix

[Wanderer]

Is it possible the rad was out to fit the new intercooler and it might just be something as simple as an air lock although the massive drop in temp on the guage would say possibly not?


Anyone know whay they ever did away with the air bleed screw on the top of most top hoses?

Ed

[Bob696]

Cheers guys

rad is in reasonably good nick.

It wasnt taken out although it was moved around by a few inches.

Sounds like I will be learning how to change the temperature sensor unit and thermostat  :shock:

Is it normal for the bonnet to get and is a kenlow fan worth considering in any case?

[turtle]

Bob,

I have got one of the Allisport intercoolers in my 90 (wow what a difference it makes:) ) not had any problems with the cooling, in fact my gauge used to sit at about 60% but now it a little lower more on the 50% mark now.

But what you are describing might be an air lock, a while back I had a similar thing, was traveling along the motorway at about 55/60 (before intercooler fitment) and suddenly the temp gauge went to max, I pulled over on the hard shoulder but all seemed ok under the bonnet, got back in the car and continued my journey and all was fine, when I got home I checked under the bonnet again, on the top of the engine is another value similar to the one on your radiator, this was released and no water was present, I toped it up and I've not had the problem since.

I hop that makes sense, something to check before you spend monies :)

[Bob696]

thanks Turtle

I hope it is that simple  :D

[karloss]

Anyone know whay they ever did away with the air bleed screw on the top of most top hoses?

Ed

Probably coz most folk didn't know what they were for anyway!!
Some stuff still have them.

[hobbit]

lot have the screw on the top of the rad, same prob though, lack of knowledge.

Metros are still a swine for air locks, even the rovers 200's were

[Bob696]

Turtle

Is your motor a 300TDi?

Seems the 200 dosnt have valve you described (on the thermostat housing?). Its just a bolted closed unit on mine

[Wanderer]

If you have a look on a V8 the one on the rad is lower than the top hose Kev.

Ed

[Bob696]

OK ...it happened again  

Had trips to cumbria wiltshire whaddon no probs but today had a gentle trip upto congelton and noticed temp igher than normal on the way up but not stressed. On the way back the temp needle got to the top of the white line  :(

Slow down and the needle dosnt want to drop by much but stop and then switch back on again and it goes to just about normal.

The only thing I did today that I havnt done on the other trips is that I had the snake head snorkal facing into the wind rather than backwards as usual (especialy in the rain).

So far I have changed header tank, sender, thermostat. I was hopeing not to have to fish the Rad out. I have a spare temp guage that I am going to fit just in case first. If anybody has ANY other ideas please let me know it is driving me nuts

[Stormin]

Not to sure about this, but does the 90 havea balance risistor like the series landies? Little silver box back of the speedo.  I know I've got a 90 but I've never needed to look. YET!  Could be that at fault.

[Porny]

Does the heater get hot???

If not sure, usual sure sign of an air blockage...

Other factors:  when was your coolant last changed???... what ratio of coolant:water are you running.  I always run a 50:50 mix (as per at work).

200Tdi's and 300Tdi's can be a bit of a pain to bleed at times.

Things you could try.... with engine running and heater on full (hot) and header tank cap off....

Give all the hoses a good squeeze... check for water movement in the header tank or any bubbles.

Remove the bung in the top of the rad and check coolant spills out.

Allow engine to warm up a bit (hold at fast idle) and check the two hoses to the heater are warming up... if not, more drastic measures may be needed!!


Ian