Temperature control vacuum harness

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Hobiecat

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I am on a quest for the vacuum harness that actuates the heater door on my ‘79 K10. Most important the boot that plugs into the heat/ac control under the dash. I am concerned a junk yard part may not be reliable simply because of the age and nature of the part(rubber).
Has anyone ever located this part in the aftermarket.
 

C10MixMaster

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from what i have seen the part under the dash is silicone and seams to last forever. the part that is in the engine compartment does get brittle and break but you can replace that part with basic vacuum hose... cant say ive seen an aftermarket source for the complete harness
 
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Snoots

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Yup.
You can still use the thin vacuum line from auto stores to replace it.
 

75gmck25

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You can buy the thin GM hard vacuum line at the store, and you can splice it or connect to it using short sections of rubber vacuum line. On the ends it should push into the large rubber/silicone fitting for the controls, and into the small fittings that go on each vacuum door solenoid.

I have considered putting a dab of hot glue on the hard line before pushing it into the rubber fitting, but was afraid I might get it in the wrong place and plug the hose.

Bruce
 

PrairieDrifter

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Lmc sells the plug I believe
 

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