Chevy k10 vacuum line questions

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tman2331

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Triston
Truck Year
1983
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K10 pickup
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305
Hey yall, I recently acquired my first chevy squarbody pickup. I was interested to know where some of these vaccum lines go for hvac. Also wondering about harmonic balancer spacing too.. any help would be great! Thanks

The defrost vacuum line to control unit has been cut. Was wondering where it goes, it is a factory ac truck

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And this vaccum line coming out the firewall with the climate control wires, would this vacuum line go staright to the intake?
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Also is there a rule of thumb of how much space should be between the harmonic balancer and crossmember? I got about 1"
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Thanks again
 

Turbo4whl

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Maybe better to see:

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Welcome to the forum. Link to the second picture:

CLICK HERE
 

Broken85

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This should get you started. Good luck.

Harmonic balancer; it is works don’t F with it. Helps to know what model and year you are working with
 

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tman2331

Junior Member
Joined
Jun 4, 2025
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Location
Kalispell, MT
First Name
Triston
Truck Year
1983
Truck Model
K10 pickup
Engine Size
305
This should get you started. Good luck.

Harmonic balancer; it is works don’t F with it. Helps to know what model and year you are working with

It's a 1987 chevy k10 pickup with an 1983 cab. Came with the tbi system and a 305. As far as the harmonic balancer, idk if it'll work until it smacks the crossmember or not. I think an inch should be plenty but not 100% sure.
 

Ricko1966

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c20
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350
It's a 1987 chevy k10 pickup with an 1983 cab. Came with the tbi system and a 305. As far as the harmonic balancer, idk if it'll work until it smacks the crossmember or not. I think an inch should be plenty but not 100% sure.
Balancer will be fine.
 

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