Temp gauge keeps going up then down?

maxheadroom · Post by **maxheadroom** » Mon Jan 14, 2008 6:54 pm

As its says in the title, went to Bridgend today via Newport from Gloucester. All well for the first part of the trip, then getting back on the M4 at Newport the temperature started to rise, pulled over plenty of water and the temperature had go down to normal. So off we set again but then all the way to Bridgend and then all the way back to Gloucester the gauge kept swinging up to nearly high and then back down to half way. It would reach top then pause for a second and then fall back to half way pause for a second then rise again. We traveled well over a 100 miles like this.
Anybody got a clue why.

Gungadon · Post by **Gungadon** » Mon Jan 14, 2008 7:13 pm

Could you have an air-lock in the system? The fact that the water level is correctly shown may not preclude an air lock.

Don

paul9 · Post by **paul9** » Mon Jan 14, 2008 7:33 pm

i drove around 800 miles with a fluctuating temp gauge,ranging from 0-3/4 on the gauge,thought it was a air lock or blocked rad,with varying warm then cold air through vents,tried everything to bleed it up without any luck,BDC even came round and helped,no loss of coolant ,but turned out the head gasket was blown in 2 places,luckily enough the head itself wasn't damaged/cracked,replaced head gasket ,after skimming and pressure testing and its been fine ever since

maxheadroom · Post by **maxheadroom** » Mon Jan 14, 2008 7:48 pm

I have just bleed the thing again and the temperature gauge has stayed at 11 o'clock and not moved, so hopefully just an air lock

Ralph · Post by **Ralph** » Mon Jan 14, 2008 8:48 pm

Thermostat sticking?

BongoMTBer · Post by **BongoMTBer** » Mon Jan 14, 2008 8:50 pm

How did the gas get get into the coolant in the first place. If the system has been disturbed then this would make senese, but if not then the head gasket could be the culprit putting exhaust gasses into the system. I hope not.

Also, slightly sticky thermostat will give the same results as it will give a greater hysteresis band when modulating the flow to the rad.

maxheadroom · Post by **maxheadroom** » Mon Jan 14, 2008 9:12 pm

new thermostat last month and guess what I changed the coolant yesterday

BongoMTBer · Post by **BongoMTBer** » Mon Jan 14, 2008 11:57 pm

There you go then. Same symptoms as my airlock, and sounds like you cured it

maxheadroom · Post by **maxheadroom** » Tue Jan 15, 2008 12:31 am

bigdaddycain · Post by **bigdaddycain** » Tue Jan 15, 2008 9:04 am

May be an idea to carry some coolant in the bongo for a bit max? Just in case?

Have you thought of a Haydn alarm? I can't speak highly enough of them....

maxheadroom · Post by **maxheadroom** » Tue Jan 15, 2008 9:24 am

Yes I will BDC and no not yet......

fingers crossed

bigdaddycain · Post by **bigdaddycain** » Tue Jan 15, 2008 2:13 pm

I've even crossed my toes for ya max...

maxheadroom · Post by **maxheadroom** » Tue Jan 15, 2008 9:28 pm

Cheers your a gent, by the way it's the water pump see my other threads.

Temp gauge keeps going up then down?

Temp gauge keeps going up then down?

Temp gauge keeps going up and then down