air bubble?

[edpryce]

i realise there is a lot on heating in the search, but nothing came to light.

if i am getting hot air from the heater, but it is coming and going, am i right in thinking this is likely to be an air block in the system?

If so, what is responsible for air in the system?

head gasket was compression tested and is fine.

84 gti.

thanks

[rubjonny]

if the coolant level drops this will cause nthe heat to cut out, but it might be down to your bypass valves.  i wrote up a coolant faq in the garage section, the method in there has never failed me when bleeding the system

[edpryce]

yup just reading that. so if i bleed it it should be good to go?

and if it does it again, is it about replacing that by pass valve with copper pipe?

ed

[Gambit]

if you have the bypass valves either replace them or cut them out they will be the cause of your intermittant heat

if you cut them out you run the risk of the matrix spliting at some point if it hasnt ever been replaced. and thats a bigger cnut of a job than replacing the bypass valves.

[edpryce]

there is no history of it being replaced. i heard changing the matrix is a massive ball ache how do people without the heater by pass valve stop the matrix from blowing up?

[Gambit]

they dont, trust me once it blows though you get a mk3 item then your safe

or just replace the bypass valves for 27 quid approx!!

[Ben Lessani]

A new matrix is only about £30 - don't bother buying the poopy valves.

Its a 3 hour job to change, probably could do it quicker, its not that hard.

[edpryce]

thanks chaps.

Am I right in thinking that driving it how it is wont do any damage other than it being an inconvienance with de-misting?

[Ben Lessani]

That and cold toes

[edpryce]

cheers.

ah least it happened after all the snow and ice (fingers crossed)