I've got a 97 300Tdi Disco with 105k on the clock. I use the vehicle for towing a 2.5tonne boat. I find that very quickly the temp gauge starts to rise (air temp or type of road doesn't matter ie country lane or trunk roads). Soon it will get into the upper reaches of the gauge, then to the red zone then past this up to the top of the "H"!!!!!! Going up or down hill makes no difference. Then suddenly the gauge will drop to normal, then up it'll go again.

My local specialist has replaced the water pump & thermostate. The centrifugal fan is ok (but possibly the next thing to replace, but he isn't recommeding an electric fan)) & there is plenty of coolant. They have said it might be a head gasket, but thats a £600 job!

Any ideas?

Sunfish

you hav'nt said if its manual or auto but electric fans should clear this problem if every thing has been checked try a pressure test to see if the head gasket has gone over hreating is some what of a problem when towing long distances especialy with an auto secondhand range rover fans will fit with few mods barry

It does not sound like the system has been bleed properly,easy way is take off pipe at thermostat top,this is a small bleed back pipe which goes to a 3 way connector going to expansion tank,take off pipe and get your laughing gear around expansion tank and blow hard while holding finger on rubber pipe,does coolant flow really well out of top flow back?it should do after a couple of puffs.then check the pipe to the expansion tank blow down the pipe does it let you blow as i have had this pipe get blocked at the plastic connector not letting air bubbles to get released from the head causing hot and then cold spots at the temp sensor causing it to rise and fall,if the connector is blocked i found it easy to clean with a drill bit hope this helps tiga.

Just a thought...

Is the engine actually overheating? Is it possibly a faulty temp sender or gauge?

Worth checking before shelling out for expensive repairs.

Jim

barryhull12 said:

you hav'nt said if its manual or auto but electric fans should clear this problem if every thing has been checked try a pressure test to see if the head gasket has gone over hreating is some what of a problem when towing long distances especialy with an auto secondhand range rover fans will fit with few mods barry

Click to expand...

Its a manual. It's temp is fine when I'm not towing if that helps. I'm nothing like a mechanic, can most garages perform this pressure test?

Thanks in advance
Sunfish

Fired-up said:

Just a thought...

Is the engine actually overheating? Is it possibly a faulty temp sender or gauge?

Worth checking before shelling out for expensive repairs.

Jim

Click to expand...

I don't think so, can the sender or gauge be easily checked?

Sunfish

Without running test procedures with manufacturers specifications, multimeter and a thermometer....no

Prob the easiest way to test it is get a probe thermometer or similar and compare temps with a similar vehicle with relation to gauge position.

Other than that you will need to find resistance values of the sender.

Good luck

Jim