running hot - help

[TDi90]

well, danny, it doesnt fluctuate, she just sits at between the half and red, and does not budge....

[extreme90]

have you got any friends close by to swap guages then  
then you know for sure then if its guage or not  
quick and easy
danny

[TDi90]

yes i do! Lord Shagg Pyle!! LOL! - HELP!
nah just joking, i might aswell just get a new guage, there is nothing else left to check...

[extreme90]

but what if it isnt that  

[TDi90]

well i *think* i have checked all else... i mean what else could it be?

[bombx3]

try a new earth from the center holding nut

[tjolliffe]

Just a thought...have you done the 'sniff test' to make sure the head gasket hasent gone? The smell of exahust fumes in the coolant will indicate a blown head gasket, equally any loss of coolant other than what would be expected normally could indicate a blow head gasket.
More often than not your local garage will do a head gasket test for next to nothing if you'r in any doubt.  :)

[Lawnmower]

my 2.5td is doing exactly this.

drained coolant, used rad cleaner stuff, changed thermostat and sender unit. reading is more stable, but sits on the edge of the white.

not sure what it is. would a dogy viscous fan produce these symptons, or a dodgy water pump.

(coolant didn't have any oil in, and engine oil is clean when it stays in there long enough).

[TDi90]

yeah its odd!! lol~!

[turbine]

Here is an unorthodox test. Partially drain the coolant.Put some food colorant into the top up water at the expansion tank. Run the motor to operating temp to ensure thermostat opens. Remove top rad hose first. Check the color of the fluid. This will tell you two things. whether or not the water is circulating; water pump. Or if you have a blocked rad core. Once you have established it's not a mechanical problem. You can move to the temp sender unit/electrics. You seemed to have covered all the other stuff. (I'd put my money on the electrical side)
I am not familiar with your engine. Is there a way to bleed the system whilst it's running. Can the thermostat housing be slightly cracked, or the sender unit, or anything else. Allowing you to bleed the system whilst the pump is running? An airlock would do much to prevent water flow aound the system. The obvious precaution is to run the motor with the surge tank cover off to prevent pressure build up. Also to not do so with hot coolant.
Hope you get sorted.

[TDi90]

cheers for all the replies... will keep everyone updated!

[paradigm shift]

I've had this problem too.. glad I'm not alone!
110 with a disco 200tdi. Always used to run just below halfway, now runs around the top of the white and sometimes smells warm. Heater won't blow hot any more. Tried changing coolant, then thermostat, then swearing, then head gasket and nothing has succeeded. Engine pulls well and appears to run fine. The guy at my local specialist suggested I'd know if she was actually overheating as it'd run like a pig.

My thinking is I've either managed to get a big old airlock which has killed the temp sender and/or water pump or the temp problem and heater problem are unrelated and purely coincidental. When it first happened I was at a rather amusing nose-in-the-air angle  :lol:

Will keep an eye on this thread gonna try the water pump next I think!

[TDi90]

before you try all that try the guage... check the earth on the guage, and maybe get a new guage, thats what im trying next, after that if she still is hot, i might look into things like water pump etc... (water pump seems to be fine though  :shock: )

R

[Xtremeteam]

I've had this problem too.. glad I'm not alone!
110 with a disco 200tdi. Always used to run just below halfway, now runs around the top of the white and sometimes smells warm. Heater won't blow hot any more. Tried changing coolant, then thermostat, then swearing, then head gasket and nothing has succeeded. Engine pulls well and appears to run fine. The guy at my local specialist suggested I'd know if she was actually overheating as it'd run like a pig.

My thinking is I've either managed to get a big old airlock which has killed the temp sender and/or water pump or the temp problem and heater problem are unrelated and purely coincidental. When it first happened I was at a rather amusing nose-in-the-air angle  :lol:

Will keep an eye on this thread gonna try the water pump next I think!

what temp sender you using?

when i had the disco engine in mine it always read high,very high,my fans come on at 92'c & that would equate to the guage of the scale :lol:

[paradigm shift]

She ran at the right place on the gauge for years, so if it is the gauge it's a recent issue.

Bottom rad hose is cold, as is most the rad, and the heater's not blowing hot. Methinks no circulation for some reason.

[drmike]

Are you dead certain that you have the right thermostat - don't some need a little hole in them - and that it's the right way round! Ran mine with no thermostat and it would show as overheating at a steady 55 because it needed the back pressure to circulate the coolant.

The engine never smelt hot so I didn't really believe it was overheating just the bit round the sender was damned hot.

Mike

[muck_truck]

it still could be the sender/gauge giving you dud info.  mine was running warm (close to red) acording to the gague with a viscous fan on.  

Now i dont run a viscous fan but use a tim temp gauge (which reads degrees) and now it usually sits about 80 and creeps upto 90 if im driving hard.  Also my bottom hose is only luke warm which would be right seeing as the thermostat only opens at 88.

id change the gauge, its cheap and easy to do before you start doing water pumps etc.

Here is a capilary one, but you will have to run some pipe from the housing into the dash. not my idea of a good idea
http://cgi.ebay.co.uk/TIM-WATER-TEMP-GAUGE-CAPILLARY_W0QQitemZ230064639117QQihZ013QQcategoryZ72205QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Here is a elctric one that i fitted but i didnt pay 33 quid!
http://cgi.ebay.co.uk/New-TIM-Black-Face-Water-Temperature-Elec-Gauge-52mm_W0QQitemZ230065394014QQihZ013QQcategoryZ72215QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

[Range Rover Blues]

Just my 2 penneth but I had a similar years ago on an old Escort.  Does you fuel guage read higher than it used to? can you tell?

The temp and fuel guages run from a voltage stabiliser so they don't go up and down with the engine revs, older ones use s bimetlaic strip heated by the current going through it, so they tick.  After a while they can break and if it sticks on you guages run from 14.3 volts rather than the 7 or 8 volts they are meant to.

Incidentlayy these things look and work very much like old flasher units

[Matt_H]

Just how hot is it running?

I believe that antifreeze isn't a very good coolant so that you're now using a liquid that won't cool as well as the weak solution that you had before.

Mike

modern antifreeze is "antifreeze and summer coolant", it moves the freezing point down and the boiling point up, it also has good heat exchanging capabilities so does cool pretty well AFAIK.

Matt

[TDi90]

well, i am at the moment in austria, so i dont have the ölandy with me, but i have changed everyting, as i have said before:

1 - a complete rad flush
2 - changed the sender,
3 - changed the thermostat -

i done it all!!

the only thing i have not done is changed the guage, but she has been running fine on that guage for ages.!!

argh its really annoying me, and im not even back home yet!!

cheers guys Rob

[Dave B]

After checking the electric gauge and regulator etc...

Check for an air lock in the head!...

You can do this when it's cold, if you modify an old rad' cap to take a tyre valve, and presurise the system to at the most 10PSI.  (Less than that will do usually, say 5PSI)  Then slacken off the highest heater hose where it goes to the heater matrix.  Gently let any air out till you get neat coolant, then re-secure the clip.  Let the air out of the resoviour and top up as needed.

If your engine is tilted up at the front slightly, then park with the front of the Landy downhill, or jack the rear end up before doing that.  Use propper stands, so it doesnt fall off, or reverse up onto a couple of old wheels etc.

Just because you get hot air from the heater in the cab, does not mean you dont have an air lock!  Ti's a common problem, but get it sorted, as the ally' head and gasket dont take kindly to being cooked.

It's also worth checking the injection timing, if that's out, it can cause over heating too, but you usualy notice the difference in the way the engine works and sounds.  Also check the oil cooler does not have an air lock in, I'll let you figure that out!  It can get messy if you are not very careful!.....

Lastly make sure your brakes are not sticking, also common, though you often notice the extra fuel it uses first, and the fact that it will roll to a stop with a bit of a jolt if thats the case.

Enjoy....

Dave B.

[TDi90]

cheers dave.
not in the country atm, but will be back soon!!
thanks for all replies