SLROC Forum

OK I have recently purchased a 300tdi disco. since I purchased it i have been having issues with the temp guage I thought it was not working as it ran super cold just below the c on the guage but once I was towing a mini digger it went up higher. so I investigated abit further and when i rev the engine the top hose preasurises but the y shaped hose from the pump doesn't feel like there is any preasure. I took many different hoses off the pump and there seems to be flow. The hose doesn't feel like there  is much preasure in them Could my pump be fluffed. I have read about other peoples problems airlocks and thermostat problems but nothing has the same symptoms as mine. My last 90 was not like this but I never ran a fan as there was no need. Is there any other test I could do to help me pin point my problem. Forgot to say the heater is warm but not very warm.
Thanks in advanced

Gary

It sounds very much like the thermostat is either jammed open or not fitted at all. I am unsure of the location of the thermostat in the 300tdi but have had experience of people removing the thermostat from inside of a housing to cure an overheating problem in other vehicles.

  Bob

Agree with above.

If the pump was goosed then the hoses would soon get hard as the motor started to cook (due to no flow)

We had issues with the BMW pumps that were fitted with plastic impellars which started to spin on the shaft but I dont know if Land rover ever went down this route (RR 4.4? P38d?? Freelander TD4 with BMW engines)

Thermostat should be easy and cheap to do.

If there is a thermostat in and its working the engine will start, the coolant will run around the engine only, when the coolant is at about 88 degrees celcius the thermostat will open and the coolant will flow around the pressurised system.
(if there was no thermostat fitted that is going to make no difference to the temperature when up and running)

I would look at the radiator and see if there is a good flow & it has not collapsed internally..

Are you running a good antifreeze ratio and do you know how to bleed a 300tdi?

I would first of all get it up to running temperature and bleed the system using both bleed points.

george

Hi Thanks for the replys. I haven't checked the coolant ratio. Mite it be best to flush the system and refill with a 50/50 ratio?
also I dont know if it reaches operating temp as the guage never realy gets above the c on the guage. how would i test the radiator? I was told that the water pump was replaced as well as the timing belt. The water pump don't look like its a new item it is very dirty.thanks for the advice.

(if there was no thermostat fitted that is going to make no difference to the temperature when up and running)

Are you running a good antifreeze ratio

If there is no thermostat fitted it will never get upto temp when driving. and will take ages to warm right up when idling

The ratio of antifreeze mix does not affect how the engine warms up.

Take the Landy for a run untill your confident it should be upto normal temp then pull over and pop the bonnet.
If the rad is hot at the top and cold/cool at the bottom then all is ok and you need to find out whether the temp transmiter or temp guage is faulty.
If the rad is cold at the top you need to fit a new thermostat and try again.
If the rad is hot, top and bottom then the engine is overheating and you will need to find the cause.
Im asuming that the coolant level is correct and it does not use water.

I am not saying run it without a thermostat,
but at this time of year with an ambient temp of about 12-16 degrees celcius it will do no harm to start and go and drive and the radiator & cooling system will get up to running temp come time.

You do want to see if a thermostat is in, Look and see (a correct thermostat for the vehicle and one that works)
you will get an idea of that when starting and the top hose staying cold untill the thermostat opens.

As to the 'antfreeze/summer coolant/rust inhibitor' it will not effect the engine warming up,
it does however raise the boiling point from that of H20 & alter/lower the freezing point.

Raising the boiling point is a good thing if you think you are going to be at a risk of cooking it.

george

Thanks I haven't had a chance to get to the disco and check.  when  I rev the engine the top hose gets presure but the hose is not that warm. I don't think there is a thermostat going by the hose not being that hot and there is not a great deal of pressure in the hose. The bottom hoses are cold. Was thinking of removing the viscous fan.I didn't have one on my 90 and it never overheated. will be going for a wee run tonight so will check it later. Thanks
Gary

OK I  had a wee run stopped checked the rad. it is warm untill half way. Got home and removed the bleed screw on top of the engine and stuck a screw driver in the hole where i think there should be a thermostat and i cant find one so I am going to assume that there is no thermostat and that aint helping my warming up issue.

Thanks for that help.

Gary