overheated...maybe

Post by **j_robi** » 05 May 2006, 22:15

myrtles adventures continue
after a good few months of behaving myrtle decided to she wanted a ride on a lorry again
on the m4 today the water temp light starts flashing, so i pull over check both water tanks- expansion tank and other full, and no signs of overheating/burning...so cautiously continue...
10 miles down the road same happens again, but all water still there, no signs of overheating
then (perhaps foolishly) continue for another few miles, get stuck in a traffic jam near port talbot, and light flashes again, so pull over immediately and concede to getting recovered
so frustrating, she's been so good for so long

theres no serious pressure on the pipes coming from the expansion tank when engine running (which is a good sign i guess)
no water comes out of the air 'thing' begind the grill (which is a bad sign i guess)
a fair bit of water dissapeared on the 50 mile journey home on the back of the lorry

all very strange

the worst bit of all is that i have to drive a fiat cinquecento until myrtles sorted...thats not a good thing

Post by **R0B** » 05 May 2006, 22:54

very odd. all the coolant there with engine running.then it dissapears when on the back of a wagon.was there not a puddle on the lorry.hopefully its a dodgy expansion tank sender..

Website · Post by **dbroada** » 06 May 2006, 06:37

what did the temp gauge show? The light is also your low coolant light which fails ON. This means a dodgy connection will also flash the light. Check your wiring to the sender it might just be that.

not that that explains the coolant loss on the transporter.

Post by **j_robi** » 06 May 2006, 07:57

ye the water loss is very strange, seeing as the engine wasnt even running
could it be a dodgy thermostat?
in terms of wiring, where are the places to look?

have had problems with wiring before on her, guess have to expect that with a 20year old vehicle mind

cheers

Website · Post by **dbroada** » 06 May 2006, 10:28

the "reporting" wiring loom is pretty awful on mine with each wire a bit brittle. Mine have all snapped just inside the crimp terminal leaving it looking OK but only making intermittant connection. Wiggle the wire going into sensors. If it doesn't feel right crimp a new connector on.

Post by **j_robi** » 06 May 2006, 17:50

wiring all appears to be solid and good connections...very unusual for myrtle!

Post by **j_robi** » 09 May 2006, 08:39

i want to check the thermostat out (as the overheating) seemed to be phantom overheating, so maybe a problem with it
where is it located? is it easy to remove?
thankyou

Post by **tonytech** » 09 May 2006, 10:16

Hot water will occupy more space thay cold, so a full tank with engine hot will be a 1/2 tank at cold.
Did you or the recovery man remove the tank caps? Are the caps on tight?

Unless your temp guage was showing hot I'd be looking at a fault in the 'low water' circuit.

T

Post by **j_robi** » 09 May 2006, 10:58

thanks tonytech, yep just realised a couple of days ago that the water expansion would be the reason for the change in water level
the temp light was flashing on the dash, so opened the expansion tank cap (was full of water, fizzled over a bit and plenty of steam from the expansion tank)

whats the 'low water circuit'?
would you say it sounds unlikely to be the thermostat?

Post by **tonytech** » 09 May 2006, 14:29

As others higher up the thread have said.
The wires to the 'Low coolant' sender in the expansion tank (not the topup tank) can break giving occasional flashing LED.

Try moving the connections around with the ignition on and see if the LED flashes.

If your temp guage is behaving normaly, ie not running hotter or colder than normal I'd think the thermostat is OK.

T

Post by **camper** » 09 May 2006, 18:29

My old 1600n diesel t25 had this problem .And you may be interested .The tempreture senser that screwed into the expansion tank has two electrodes .I used some radweld to cure a water pump leak this caused the senser to flash the overheating light .Over a period of time the radweld had built up a gung between the electrodes which then become non conducting.

Post by **j_robi** » 10 May 2006, 12:10

is the temp sensor/low water circuit the lead that goes into the top of the expansion tank?
if so they appear to be ok

Post by **tonytech** » 10 May 2006, 13:10

Temp sensor is in thermostat housing.
Low water sensor in expansion tank.

I've had problems with a similar circuit on a VW Polo that flashes for absolutely no reason at all.
But you need to be absolutely sure you know what is happening in the cupboard under the bed.

T

Post by **j_robi** » 10 May 2006, 13:17

"cupboard under the bed"...? sorry if im being dappy!

so i guess its the low water sensor that iv checked
in order to check the temp sensor, do i need to take the thermostat off and try it in a mug of hot water or something?

Post by **tonytech** » 10 May 2006, 13:38

j_robi wrote:"cupboard under the bed"...? sorry if im being dappy!

so i guess its the low water sensor that iv checked
in order to check the temp sensor, do i need to take the thermostat off and try it in a mug of hot water or something?

Cupboard under the bed = engine bay (most campers have a bed over the engine)

Temp sensor in thermostat housing sends signal to guage on dashboard.
If your guage reads OK leave well alone.

Thermostat testing leave well alone unless you suspect it isnt opening or closing properly.

I cant see any idication of overheating in your post.
I'm pretty sure you just have a electrical problem.

T