Heater hoses

[Rbstuartjr]

Hi everyone, it seems that my heater hoses are leaking right above the passenger side frame rail on my trailblazer ext. So I figure it's time to replace them. When I went to look up the part numbers on the diagrams, it seems that since they are no longer available the part numbers are not labeled anymore. I went to rock auto and they have a whole bunch of heater hoses listed with their applicable part numbers. Looking at the attached diagram the hoses that are leaking are #9 and 19. I was gonna replace 21 while I had everything apart as well. I have tried researching these part numbers before asking on here, so if anyone can please let me know the part numbers I would really appreciate this. Thanks

 

[The_Roadie]

I have a 10 MB PDF of part numbers useful for body shop quoting, and they don't show those parts either. Odd. How about fabricating them from generic hose?

 

[warriorpluto]

I ordered everything on this page and replaced all the heater hoses. I have an sle.

http://parts.nalleygmc.com/showAssembly.aspx?ukey_assembly=397095&ukey_make=1026&ukey_model=14570&modelYear=2003&ukey_category=19494

 

[The_Roadie]

The EXT in the OP's post is different, and includes a valve (#23) that the short wheelbase trucks like yours and mine don't have.

 

[Midnyteryder196]

Not meaning to hi Jack.. But roadie do you happen to know exactly what that valve does? And what size the ends are for the vac line to it?

 

[Rbstuartjr]

Roadie, that's what I'll probably end up doing. Figured since the parts are available it would be easier to do a simple swap.

Midnyte that's the heater control valve for the auxiliary heater in the rear on the Ext versions. As to the size of the vacuum line ends, I'm not sure.

 

[Midnyteryder196]

Thanks. Is it supposed to work not even being hooked up to vacuum lines? Mine does n has me thinking that maybe the valve is bad.

 

[The_Roadie]

I don't have one to measure. The valve is indeed to close off hot coolant from going to the rear in summer. It's electrically controlled, with vacuum boost. If you care to manage manual valves or bypass hoses, you could run without the valve. How could you have one and no vacuum going to it?

 

[Midnyteryder196]

The hose had a crack in it and had to take it off as I wasn't around any part stores. And just never got around to putting the line back in. I capped the manifold outlet and have been running like that for almost a year.

 

[Rbstuartjr]

I believe those vacuum hoses are parts #1 and 2 in the above diagram. If that is them, then, they are still available from chevy.