Boil over when switched off

[pinky]

If Triumph reckoned you needed a hole in the top of the housing they would have put it there simples

Hi neil

 

They probably considered dangerous, it comes out like a presure cooker you have got to be careful

When you do it

However it works well

Lots of modern cars have a screw fited in the system to purge the air out

 

Pink

[smizgals]

I recall reading (TR6 Registrar?) some while ago that there was a Triumph change order to retrofit 13psi caps for a whole range of models. However, make sure the heater and its pipes is in a servicable.

 

Stan

[Phil73TR6]

Thank you to all contributors for your observations and advice. Here is my feedback.

 

I received the new stat(s)and rad cap. It was immediately noticeable that the replacement rad cap seemed much stiffer than the one (brand new) I had previously fitted - even though they were both stamped at a rated 13psi.

 

The replacement 82deg C and the fitted 82deg C (brand new)stats were identical in that they had a bleed hole, fitted with a tear drop shaped loose plug. The 74deg C stat I bought as a 'maybe need to fit' did not have a bleed hole at all however!

I fitted the replacement 82deg C stat having first cut out the tear drop plug to leave the plain 3mm dia hole. I figured this would make next to no difference to the initial heat up but would ensure air could bleed through the closed stat when filling.

 

My last tests had come to a halt because a small leak had developed from the top of the heater water valve. I fitted a new valve taking the opportunity to fill the system via a heater hose rather than the rad cap. In fact I temporarily fitted a 'flat' valveless rad cap to seal the top of the radiator but still allow air to escape without spilling over the engine bay. This also allowed a slighly higher head of water to be put into the system and displaced air to be seen bubbling into the overflow bottle. I could fill until coolant came out of the water valve, indicating the block, head and heater matrix were full.

With the replacement 13psi rad cap fitted and everything tightened up the cooling system now seems to be operating exactly as it should.

 

I am fairly sure my initial problem was an airlock which did no allow the system to fill (after the rebuild everything was bone dry, including the heater matrix). Filling via the heater hose must help in this regard.

 

Although the system still cannot be completely filled from scratch as the top hose is higher then the rad cap, it should, as respondents have explained be 'self bleeding' following a couple of heat/cooling cycles.

 

I hope I can now move on to something else - lets see, whats next on my 'snag list' ...............

[jamesStag]

Hi Phil,

Thanks for the feedback - its always good to hear how someone gets on. Great to hear that problem now seems to be resolved and usual operation is restored..!

 

Cheers,

J.