heater

1986 GMC JIMMY
150,000 MILES • 4WD • AUTOMATIC
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SEAWOLF
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  • 2 POSTS
I have a 1986 k5 blazer 305 ,recently i installed a 350 out of a 78 gmc pickup,since then the heater will not switch to defrost or vent,have lots of heat and fan works fine Did i miss a vacum hose?.I see a 1/2 inch one near the firewall,seems to enter the cab below the fuse box,its not connected to any thing???
Jan 4, 2011 at 4:56 PM
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DOCFIXIT
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Yes vacuum is problem without heater controls go to default. That hose off could be the one but see diagram hose will come from vaccum tank and should have a check valve. Maybe still on old engine
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Jan 4, 2011 at 6:04 PM
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SEAWOLF
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Found hose(more like a small tube)hooked it up works fine thanks.I skipped by it several times ,thought it was an electrical(push on)connection,Thanks foe you're help
Jan 6, 2011 at 8:39 PM
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