overheating 90 with 300tdi

[v40mav]

Have recently bought a E plate 90 which has had a disco 300 tdi engine installed retaining lt77 gearbox.

On travelling to site ( on motorway for 25 miles )  yesterday the temperature gauge rose hitting red  
Things settles down and throughout the day off roading the gauge was exactly normal.

Checked the levels and everything obvious. Because its had a 300 tdi engine there is about a 8 / 10" gap from the Fan to the radiator. It has been suggested to check the thermostat but the heater is working fine so perhaps rule that out. Radiator is not in great shape but no leaks etc. Any suggestions that I can check to start to narrow down causes.   :?:

[Xtremeteam]

was it yourself i spoke to yesterday at lamancha with the red 90?

[v40mav]

Hi Mike

yep it was me - despite all running yesterday it was ok until hit M8 on way home - Was talking today to a chap earlier who thinks it may be head gasket. suggested a pressure test  :?:

Have ordered a new radiator and will tackle putting an electric fan in due course but don't want to cause any further damage meantime .

I'm away this weekend and will take the disco but was looking to have defender back for the following week.

Hugh

[Xtremeteam]

Hi Mike

yep it was me - despite all running yesterday it was ok until hit M8 on way home - Was talking today to a chap earlier who thinks it may be head gasket. suggested a pressure test  :?:

Have ordered a new radiator and will tackle putting an electric fan in due course but don't want to cause any further damage meantime .

I'm away this weekend and will take the disco but was looking to have defender back for the following week.

Hugh

Honestly do the radiator & lecky fan first n then see how u go

is your heater ok n blowing hot?

also as i said move the air filter as i found that made mine run hot

anychance u could take some pics o your pipework as after seing yours im considering fitting a 300

[v40mav]

Heater is fine.

Tried to track down a second hand air filter holder as suggested but - failed today.  

when fitting electric fan how would you connect this in - I'm nnot close to local scrap dealers - any suggestions ?

I'll take a few pick and post them up later -

exactly what pipework do you want to see.

[Ben]

Hi v40mav

Is there any cowling around the fan to help pull the air through the rad? To be honest, it might be as simple as fitting this if it doesn't already exist. This will help pull the air through the rad at speed - sounds like the cooling system's fine, but the effectiveness of the fan is being lost when you're on the motorway.

Worth a try if nothing else while you wait for the rest of the bits to arrive.

Cheers

Ben

[bigfatsi]

Have you checked the temperature with a thermometer? If the car is still using an old TD/NA Temp gauge, it will read high as the 300 runs warmer. My 200 engine is fine but reads just up to the red due to calibration for a different engine. If it's idling it will sit in the middle and only moves to the upper end after a good run but remains stable and predictable ie it may move slightly higher after a big hill, lower when pottering about at low speed.

 Check it with a thermometer and if it's ok it may be worth swapping your gauge for one that's calibrated in degress rather than white/red.

I'm not saying you don't have a problem, but I'd check it out first before you go spending money! HTH

Simon.

[Ben]

Good point bigfatsi

I'd forgotten something about my overheating problems until I read your post...

My 300 was from a disco, and I had the disco sender unit in the engine... The temp gauge did silly things until I put a defender 300 sender unit in...

You can get those temperature gun things (point at the engine and press a button and it give the temperature) fairly cheaply from screwfix etc.

Cheers

Ben

[mmgemini]

Lots of things can cause a problem on this conversion.
What concerns me is that at times the gauge seems to be correct. I always advise that the correct matched sender for the gauge is fitted for the temperature gauge. IIRC there are two senders. One Discovery one Defender.

Also because of the intermittent over temperature reading I would be checking the thermostat. That is a cheap option.

Also do as Ben suggests. Check the actual temperature.

A couple of other points.
When you fill a 300Tdi with coolant you must follow the correct proceedure. Failure to do that wil give false readings on the temperature gauge.

Fill the header tank.
Then fill at the top of the thermostat housing until the radiator is full. Work the top hose to gat rid of any air locks.
Then fill to the top of the thermostat housing, again make sure no air locks. Then top up the header tank.

Secondly. The viscous fan can fail. Not easily reconiasble this one though. It can appear to be OK BUT it runs at such a speed that it actually stops the airflow through the radiator. Take the fan off and road test the vehicle. A 300Tdi should run happily on a road without the fan.

HTH