rad cap blowing off

[markthe45king]

i feel stupidly thick - i was told this on sunday at the rally, but it's been a mad few days - my rad cap has blown off twice recently (in traffic, and in front of a coach on the way to the rally!) - and it's clearly an overheating problem, but i was told that if the rad was hot at the top and bottom then it's not blocked - is that right? If so then it's the stat?

the other thing is that the clutch pedal is now very soft and i've picked up a rattle on those rare occassions i keep the car in gear when the brake is down - i'm thinking a) don't sit at lights in gear!! and b) clutch / hydraulic fluid?

hope you all enjoyed the national - has anyone complained about the roads either way into kelmarsh having recently being regravelled?

[chrisryder]

what's the water level like in the rad? if you're filling it to the brim, the rad will blow off until it reaches its own desired level.

Do you have a temperature gauge fitted? It would be an easy way to tell if it is overheating...

[bmcecosse]

NEVER sit with your foot on the clutch........you may have worn away the graphite bearing - it's engine out to fit a new one..... As for the overheating - it's 'never'' the thermostat...... Either the engine is producing too much heat - or the water pump is not circulating properly - or the cooling system is bunged up - or the radiator is bunged up on the air side - or has many fins missing....... Very first check - is the fan belt tight?? Give the cooling system a very thorough flush out with rad flush (or drain cleaner)....... And check the air side of the rad (hose pipe it through - and open up any closed-over fins).

[simmitc]

Check compressions in all cylinders - a leak into the cooling system will easily blow off the rad cap.

[MColes]

it's 'never'' the thermostat......

Another quote to add to my repertoire along with that other well known one

[bmcecosse]

I've never known one to fail closed....... And like the coil - many are changed needlessly at considerable cost!

[lee_rob]

My thermostat failed recently and that was only 10 years old.....

[bmcecosse]

Did it fail closed??

[lee_rob]

Nope, it stuck open and the engine was running over-cool never got to temperature. Changed it and it now get to 80 degrees in less than 5 mins

[Dean]

my rad cap has blown off twice recently

My nipper does it all the time, I blame Heinz.

Are you feeding it too much fibre?

[bmcecosse]

'stuck open' - good! Never known one to fail closed......

[lowride stepside]

'stuck open' - good! Never known one to fail closed......

Ive had coil fail on my mog and i;ve seen stats that dont open ,on bikes, and i been done seen about everything when i see an elephant fly.

[bmcecosse]

[lowride stepside]

speechless

[autolycus]

Is anyone still using bellows-type thermostats? Or did they all fail (closed!) years ago and get replaced with wax capsule ones. Here's a failed (closed) thermostat: heat it up and it blows bubbles from the bellows.
[frame][/frame]
£174 for a new one (it's not out of a Morris)

Kevin

[bmcecosse]

Crikey.....