Hi.

So i have a 258,000 mile disco 1 300tdi.

Now i bought it a little while ago its an off road toy, its not in great nick but i only paid £500 for it so i knew id have to do some work.

when i got it, it drove fine, little bit gutless but i put that down to the clogged up intercooler and EGR valve (EGR blanked off now and intercooler cleaned with new hoses)

but i now have an overheating issue, driving back from an off road event i noticed the lovely temp gauge creeping up, i pulled over and found that the Expansion tank had split and poured water everywhere.

Replaced expansion tank and cap a few days later, re-fitted and left it running in the yard for about 40 mins on idle, temperature reached just below centre (normal) and stayed there. i locked it up and thought i had sorted it, on the next outing, within 2 miles of home it started overheating again, so i turned around and parked it up.

iv done all the standard checks (foaming of oil cap and looked for any oil in the coolant) but i don't really wanna start stopping the head down without being absolutely positive!

this morning i stripped the coolant assembly and replaced the water pump with a brand new Bearmach unit and a new gasket.

I'm going to be doing a flush probably tomorrow due to the beautiful rain we currently have lol. iv got all the flushing chemicals and replacement coolant.

is there anything else obvious i can look at before taking on the dreaded head gasket.

Also is there anyway of me finding out what Headgasket i have (1,2,3 hole) without stripping it down first so i can order all the bits if needed.

but preferable could you lovely people tell me that the head gasket is fine and i don't need to do it please lol.

Regards,
Nick

its not got mud clogging the radiator fins has it, as you said it happened on your return from an off road event

Yer I jet washed it in leaving the event, iv also checked behind the radiator and that's clear.

jet washing yr rad can wreck it! fins get bent over and block air flow etc.

it might be worth changing the thermostat, even it appears to be working and cutting in at the right temp it may not be opening fully? note it is bypass type so removing as a test to see if it the cuase of the problem is not an option........

the heater matrix helps keep things cool even with the heater turned to cold, but im not sure if it does THAT much cooling i assume yr heater is working?

I had a similar problem, and found out it was my radiator that was knackered - had no cores left in it!

So replaced it and never had a problem since.

I changed the thermostat with the water pump yesterday as I assumed that could have and adverse effect on the cooling.

Now when it comes to the heater it's difficult to say, the fan for the heater is pretty knackered but you can feel heat coming through once it reaches temperature.... Is there a way of me connecting up a hose to a pipe going into the matrix to try and flush it through....?

StuRox said:

I had a similar problem, and found out it was my radiator that was knackered - had no cores left in it!

So replaced it and never had a problem since.

Click to expand...

But surely the radiator having no cores ect would cause cross contamination of liquids..... Which I have no evidence of at all....

njz9046 said:

But surely the radiator having no cores ect would cause cross contamination of liquids..... Which I have no evidence of at all....

Click to expand...

Cross contamination of which fluids? There should only be coolant in the RAD cores even if the it has an oil cooler heat exchanger built in.

I had a difficult time diagnosing my over heating issues after trying everything. Eventually, with the advice of some unknown gent, it became apparent that the system wasn't self bleeding. The whole issue was solved by removing and cleaning the breather pipes and valve. That's the pipes that run from the top of the rad, top of the stat housing, through a circular valve and to the bottom of the tank.

You can flush the heater matrix by removing the left water pipe on the bulk head while having the 13mm? drain plug removed on the engine block. Best to fill this manually when refilling system.

Thanks for all the advice, had my mate pop over as he was in the works van on call and he did a pressure test..... Quickly followed by him ripping the head off and telling me he will be back when iv got all the bits.
Ordered a re-faced head and need a new gasket, am I right in thinking the 3 small holes in a line indicate it's the "3 hole gasket" wanna get it ordered up ASAP so should be up and running by Sunday.

njz9046 said:

Thanks for all the advice, had my mate pop over as he was in the works van on call and he did a pressure test..... Quickly followed by him ripping the head off and telling me he will be back when iv got all the bits.
Ordered a re-faced head and need a new gasket, am I right in thinking the 3 small holes in a line indicate it's the "3 hole gasket" wanna get it ordered up ASAP so should be up and running by Sunday.

Click to expand...

Well it means a 3 hole gasket was last fitted. Either measure piston to head clearance or if in doubt fit new 3 hole gasket its the same as the one you've took off . I did when I fitted my new head, not had any probs.

So was it definitely the head then?