Rear Heat Shut Off

[landtoy80]

As I get ready to replace the heater hoses I had an idea Rear heat shut off
With the rusty rear heater pipes it might come in handy when they rust through.
Anyone done it?

 

[tusk74]

I just had my rear heat pipes replace with rubber heater hose. The radiator guy I always go to said most of the aftermarket rear heaters use rubber heater hose all the way back, even on conversion vans. He assured me there would be no problems with rerouting the hose along the top of the frame. This would be good info for anyone trying to relocate their converters, but I guess it's not the info you were looking for. I posted a thread about rusty rear heater pipes a while back and I think you chimmed in about installing a shutoff valve on both of them. I think it's a great idea, especially in the summer if you frequently have a passenger. Other than that, I'd just cut the pipes near the transmission tunnel and bypass the rotted metal pipes with heater hose. IIRC, there are a couple of places along the length of rear heater pipes that have pieces of heater hose connecting the metal pipes. I think one long length of hose beats several pieces of metal piping joined with heater hose. The less joints, the better.

 

[landtoy80]

Is the rear heater hoses 1/2"?
I tried to measure the pipe and I got 1/2" so some 1/2" shutoff valves should work.

 

[tusk74]

The heater hose used was 5/8 if IIRC. If you crawl under the truck and look at where the 2 pipes attach to the rear heater core you'll see what size hose to use.
Where do you plan to splice in the shut-off valves?

 

[landtoy80]

The outside of the rear heater pipes on mine look to be 1/2"or about 13mm. The other heater hose pipe I could measure is 17mm or about 11/16".
Wow do measure heater hose? inside or out side of hose.
And with the pipe, its outside right?

Note: my measurements are with a $1.99 micrometer set so the numbers may be correct.