Question about free wire of glow plug system 6.2l Diesel

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

German_fall_guy

Junior Member
Joined
Jul 28, 2019
Posts
25
Reaction score
5
Location
Germany
First Name
Steffen
Truck Year
1984
Truck Model
K20
Engine Size
6.2 Diesel
My truck arrived yesterday and a got some questions about the truck. It is a 1984 K20 with 6.2l diesel engine.

in the first picture is a wire that comes out the glow plug wire loom on the driver side but all glow plugs are connected an no glow plug is missing a wire with connector also the coolant water sensor on the right side of the engine is no wire missing also. The color of the wire is green.

the secound picture shows glow plug controller switch but the middle bolt don’t have a wire. Is it correct? It looks like a bypass. It is a california truck but we have cold days right here. It the bypass good?!

So any help is welcome. Thx

You must be registered for see images attach


You must be registered for see images attach
 

Blue Ox

Turning Diesel Fuel Into Fun
Joined
Mar 27, 2018
Posts
5,186
Reaction score
11,896
Location
LI-NY
First Name
Derek
Truck Year
MCMLXXXV
Truck Model
K20HD
Engine Size
6.2L
I believe the extra wire is for the indicator light on the instrument panel.

They changed the whole relay and controller system in '85 so yours may be different than mine, but that's how mine is set up.

That solenoid does look like it's bypassed, which is not good. The glowplugs will not survive being on all the time. You're going to have to trace things and see what's up.
 
Last edited:

German_fall_guy

Junior Member
Joined
Jul 28, 2019
Posts
25
Reaction score
5
Location
Germany
First Name
Steffen
Truck Year
1984
Truck Model
K20
Engine Size
6.2 Diesel
where is the connector located for the indicator light on cluster
 

Blue Ox

Turning Diesel Fuel Into Fun
Joined
Mar 27, 2018
Posts
5,186
Reaction score
11,896
Location
LI-NY
First Name
Derek
Truck Year
MCMLXXXV
Truck Model
K20HD
Engine Size
6.2L
I'll have to look at mine tomorrow. My recollection is that the glow plugs/water in fuel lights have a separate harness that has it's own hole and grommet to pass through the firewall.
 

Blue Ox

Turning Diesel Fuel Into Fun
Joined
Mar 27, 2018
Posts
5,186
Reaction score
11,896
Location
LI-NY
First Name
Derek
Truck Year
MCMLXXXV
Truck Model
K20HD
Engine Size
6.2L
I tried to trace it, but it all kind of disappears into the main harness. My best guess is it's a three wire harness that goes through the firewall just below the fuse block. If you have cruise control it's right next to that one.
 

Latest posts

Forum statistics

Threads
43,983
Posts
947,108
Members
36,039
Latest member
1986 Hooligan
Top