300tdi Overheating

[Scruffdog]

Hi All,

I am looking at buying a 99 disco 1, 300 tdi manual.
It is in getting fixed at the moment to replace a cracked head from overheating.

I was wondering what would have caused this (open statement) or what I should be looking at to make sure nothing else is dammaged?

The owner thinks it may have been a stuck thermostat, but was not sure?
I know there is a problem with the V8s with a slipping cylinder sleave, but I could not find anything about the diesels.

Regards
Mark

[red90]

Most of the time, it is the viscous coupling on the fan not working. They die quite frequently.

But it could be something else as well like the thermostat.

[DK]

Could be numerous things.
Water Pump "P" Gasket leaking
Shot water pump.
Thermostat
Fan

If something goes wrong they get hot real quick and sometimes its too late before you realise.

Personally i would stay away from it

[Scruffdog]

It has me worried why, might give it a miss,

[Loanrangie]

It has me worried why, might give it a miss,

If its getting a new head and the bores arent badly glazed then there is no reason not to buy it, it will be good as new if it has been repaired correctly.

[andrew e]

Just get a mechanic to test for exhaust gas in the coolant before you buy it to make sure the block isn't warped, and it will be fine. Mine started out with a stuffed welsh plug and went from there.



Andy

[cookiesa]

There are a couple of badly designed parts to the cooling hoses that allow them to get damaged quite easily too. It is worth checking them all and cutting up some old hoses to make up some protective covers. The 2 main I protected on mine are the heater ones that run along the back corner of the block and also the top radiator hose.

The heads on the 300tdi are not very forgiving and the temp gauge is useless. by the time it registers it is all over red rover.

And get yourself a low coolant alarm!

But they are a great engine if your not a go fast person and like economy. If you plan on doing lots of mid to heavy towing and want to do it at highway speeds then probably not the best choice!

Mine runs cool now even on a 49 degree day with the aircon flat out at 110km/h If your gauge moves much from "running temp" then there is probably a problem with the cooling system somewhere. t is worth getting the radiator "rodded" and properly cleaned.

[matsmad]

Mine is fine normally but hits the big H when towing my boat on the freeway after a long period of acceleration up a hill

[cookiesa]

Thats how mine started. Even after having the cooling system flushed (which was clean apparently), new water pump etc etc. Then it slowly started getting worse. It would then do it overtaking etc.

After having the radiator rodded it fixed it and now is back to it's old self. Apparently the pipes within these radiators are quite fine and can block easily over time.

[NHV6]

i just bought a 99 300tdi that was overheating. I got the radiator cleaned and it turned out that the baffle in the tank that stops the water from flowing straight from the inlet to the outlet was broken and no water was flowing through the radiator. This also caused the head gasket to go, lucky the head was ok. Had it tested and it was just slightly warped. Anyway, from what i understand if you have a cracked head or blown gasket, the water will be pushed from the engine out the expansion tank. Seems thats the easiest way to tell. Long story short, if the head is replaced and it still overheats then it could have been the radiator that caused it to go in the first place.