pre cat heater. Is it meant to be this crap?

[Russell Mc]

Need a bit of help here with the heater on my pre-cat. Basically its next to useless.
There just isn't any hot air coming out the blowers. All the speeds on the blower work but it just seems to increase the noise rather than the heat.
The heater valve seems to be working and there doesn't seem to be a block in the heater matrix as the in and out water pipes to it get hot.
I want to be able to use the car all year round but the way it is at the moment I doubt it'll be able to demist the screen.

I took a couple of pictures as there is a hose just hanging down. Is this meant to be there or does it go anywhere?


The pipe comes from the passenger vent


It hot air supposed to come from here or does that pipe connect here?



Cheers

Russ

[SSPPGG]

the loose pipe is supposed to be connected to the round vent

[black and green]

I've spent a few interesting hours trying to get my heater to play ball. The things that made the most difference to mine were bleeding all the air out of the system and getting the heater control valve to open fully - mine was seized almost shut (enough to let a small flow of water through, but noe enough to actually get the matrix hot).

I've also blocked off the dash vents - this means that air from the blower can only go to the screen or the footwells. On full heat and max blower speed this is enough to clear the screen and keep it clear, even in the crap weather of the past couple of days.

[Russell Mc]

How did you bleed the matrix?

Im going to connect this pipe back into where its supposed to go. Hopefully that will give some heat to the screen.

[black and green]

I clamped the flow and return pipes to the matrix, disconnected them and extended them using garden hose. Then removed the clamps and flushed out the matrix with water until it ran clear. Clamp again, reconnect and run engine with pressure cap off as per normal engine coolant bleed procedure.

I think that I could have got away without bleeding the matrix separetly, but my heater control valve was full of gritty crap and I wanted to flush the matrix to make sure it wasn't blocked.

[Barreti]

Russell MC, if you're going to the trouble of pulling off the hoses to make sure there is no air in the matrix then clamp the hoses behind the valve and take the valve unit out.

That way you can make sure it is all set up correctly and nothing is damaged.
Also, open and close the valve to its fullest, and look through the hoses to make sure the valve is properly open and closed and there are no obstructions.
There is no reason why a properly setup and working pre-cat heater can't work to an acceptable level.

And yell if you're still having problems. It might be nessary to do sort it out in stages.

[Russell Mc]

The hose is too short to reach where its supposed to go. Seems its been broke or has been cut in the past.
Anyone know where I can get some more of it from?

[black and green]

I got some at local motor factor - its just plain ordinary heater hose

[Barreti]

Russell,

This thread Clicky explains how the heater motor works and has useful pictures.
One other thing - the top photo shows you down through the valve.
The valve is fully open in that shot yet that lump in the middle restricted flow about 50% and after 5 years of ownership I drilled that out last year and fixed my heat problems instantly.
I don't know if the valve is original or if its a replacement off something, but if you are pulling your valve out to sort out the electrics and that its aligned correctly is worth having a look through the valve.

IanB

[Russell Mc]

What I may do it get a new heater valve first then make sure its fully opening and closing with the motor.

I see the part listed here.
http://www.clever-trevor.net/TVR/Parts_details/P01...

Isn't this the same part but ummmm slightly cheaper?
http://www.ebay.co.uk/itm/HEATER-VALVE-NEW-VW-CADD...

[black and green]

Russell Mc said:

What I may do it get a new heater valve first then make sure its fully opening and closing with the motor.

I see the part listed here.
http://www.clever-trevor.net/TVR/Parts_details/P01...

Isn't this the same part but ummmm slightly cheaper?
http://www.ebay.co.uk/itm/HEATER-VALVE-NEW-VW-CADD...

Yep - functionally identical.

[SSPPGG]

bit of a hijack, but my valve seems somewhat different to the one in the clevor trevor an ebay link, but the same as the one in the clicky, and i cant find a replacement anywhere. any ideas where this may have originated?

Edited by SSPPGG on Tuesday 31st January 17:44

[Russell Mc]

The original style is no longer available and has been replaced with the one on the site

[Barreti]

It looks like it might fit with a bit of coercion SSPPGG
another clicky