other Silly Question?

[ingramlee]

Guys,

 

Quick, possibly stupid question. Is it possible to replace the heater valve without removing the heater box from the dash? I have seen Marshall's very nice article on refurbing the valve but it was already out of the car. I have a new valve on the way but I really! really! really! dont want to drop the heater if I dont have to. I apologize if this is a stupid question.

 

Thanks,

[williamggruff]

Not a stupid question, and yes, you can replace the valve without removing the heater from the car.  The valve is (or was, as the case may be) fixed to the back of the heater box with short bolts/screws, and is also situated between a short section of hose that exits the back of the heater box, and a longer section of hose that connects to the back of the cylinder head.  The challenge is to detach the valve from the back of the heater box without breaking the plastic flange that holds the valve in place.  By removing the hose clamps that secure the valve between the sections of hose, and loosening the clamp that secures the activator cable to the valve, you should be able to remove the valve from the car and replace it.

[PaulTWinterton]

The heater valve is behind the firewall on the passenger side of the car. It's accessible from the engine compartment. Disconnect the hose to the engine. 2 small bolts hold the valve in place, but the heads of the bolts are hidden from view so it's a little difficult to remove. I've used a mirror to understand the orientation. Do not force anything. The mount for the valve is plastic and easily broken. Not the end of the world but avoidable.

There is one more bolt to remove. It holds a lever to the backside of the valve. Remove the bolt. DO NOT DISASSEMBLE THE CABLE FROM THE LEVER.

Once the valve is out of the car, note the orientation of the cable/lever, in-car setting (hot/cold), and the valve setting itself (open/closed). You will want to make sure the new valve is set the same way.

[Benjamin A.R.]

I'd rebuild the heater box while you're at it, it's not as bad as people say. It's just a little tricky getting all the cables adjusted.

[M3M3]

yes.  no major removal work needed.  valve is fairly accessible in the cowl.  here is link to an entry in my build thread with removal detail

 

http://www.bmw2002faq.com/topic/103584-mlytles-m2-madness/page-43#entry963608

Edited February 6, 2015 by mlytle

[bento]

Be careful loosening the nut clamping the cable to the valve lever. Mine was rusty, I was not careful, and ended up bending the cable 90 degrees trying to loosen the nut, then broke it trying to straighten the cable back out.

[ingramlee]

Thanks everyone for your responses, especially Marshall's build thread. Once I get the new valve I should be able to get it installed without too many issues. Hopefully!!

[Hans]

That said it would b tempting to change the 40 year old hose from valve to heater. Sometimes you can GENTLY cut a slit in the hose over the connection - a dozen or so shallow repeat cuts minimizes strain.

['76mintgrün'02]

I agree with Hans, be very gentle.  I put a little strain on the hoses going into the heater core on another seventies vehicle and it made the core leak.  The core was only fifteen years old, so they can be delicate... not to say don't do it, just be GENTLE.