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Old 02-13-2018, 11:43 AM   #51
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Join Date: Mar 2016
Location: Cbus, Ohio
Posts: 72
Re: '78 K20 to C10. Almost 20 years in the making.

I decided to try and use the mechanical trans linkage kit work as I wasn't sure the cable shifter would fit on my column.

I had a friend weld an extension onto the stainless rod that came in the kit.

I made a rough template of how I wanted the linkage to route from a hanger. I then used some map gas and the vice to bend the rod. After a couple adjustments I came up with this.

It works really well, surprisingly. I wasn't sure it would work right with the bends and heim joints but it does. So that's done.


I spent 2 hrs fixing the brake line leak in the rear of the truck. I had to use an inline flare kit and the old bar clamp style vice-gripped together to keep the line from slipping through the clamp. Eventually it was done and sealed. I replaced the hose as well as it was distorted from me overtightening the goofed up flare.
Right now I'm working on rewiring the dimmer switch and the wiper switch. I'm just extending the dimmer wires and cut the connector down and it plugs right in. I ordered a wiper delay module and then Ill be cutting the factory cab side connector off and wiring the existing wires to the connector on the delay module.

Last edited by cruizin01; 02-13-2018 at 11:51 AM.
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Old 02-20-2018, 10:35 PM   #52
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Join Date: Mar 2016
Location: Cbus, Ohio
Posts: 72
Re: '78 K20 to C10. Almost 20 years in the making.

Few things to update.

I was able to modify the stock battery brackets to hold this larger AGM battery. Its not super pretty but its hidden by the battery. It needs painted, etc yet it works. I need to come up with a hold down but yeah.

I used some battery cables I had laying around at work. The positive cable was perfect length and the negative was 1/0 speaker cable I had around. I found some crimps and some heat shrink from harbor freight.

I also mounted a universal coolant tank and got it connected. It was easier to mount etc than a stock one that I didn't have...

Sunday night I got to the point where I was ready to try and crank the engine over with the key! It fired right over without any issues. I didn't have any fuel in the tank so I wasn't ready for it to run yet.

Last night I topped all the fluids and put some fuel in the tank. I still dont hvae the right filler neck or hose but I used some heater hose and a funnel to dump in a few gallons. It struggled to start and was dumping fuel badly and running poorly. I realized after talking with a friend that my choke wasn't working right. I got that handled tonight and made another attempt.

Finally running after a few fixes.

Tonight was the first time Ive ever driven this truck under its own power. Pretty stoked about that.

Please excuse the poor video. My wife texted it to me instead of email.

I still need more coolant. I feel like this things holds a swimming pool full of coolant. The trans is pretty close to topped off. It was hard to read in the dark. I had the fan running to keep things cool.

Transmission seemed to go into 1st, neutral and reverse just fine. Thats a nice relief. Brakes worked so far. Pedal seemed a bit low but not spongy.

More to come. ..

Last edited by cruizin01; 02-20-2018 at 10:41 PM.
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Old 02-21-2018, 03:24 AM   #53
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Join Date: Dec 2009
Location: Fairbanks, AK
Posts: 1,668
Re: '78 K20 to C10. Almost 20 years in the making.

Good progress! Nice to hear it make some noise. Battery looks fine. You should see the box the previous owner of my plow truck rigged up to hold a 4D battery...

1991 V3500 L29 454 4L80E NP205 D60/14 Bolt 4.56's
1984 K30 292 TH400 NP205 D60/14 Bolt 4.56's flat bed 7'6" Meyer Plow
Project Daily Driver
Project Heavy Hauler
Project Plow Truck
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Old Today, 11:29 AM   #54
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Join Date: Mar 2016
Location: Cbus, Ohio
Posts: 72
Re: '78 K20 to C10. Almost 20 years in the making.

Couple small updates.

I finished all the wiring for the trans controller. I haven't gone through the setup yet as it recommends the engine being at operating temperature and I don't have the fan wired yet. But the controller is working, etc. I'm not sure where I'm going to put this thing. Its slightly larger than I was expecting. Id like it to be in plain site as it will be my only source for MPH until I go with a newer gauge setup. I may just by a clamp style cell phone holder and stick it on the bottom side of the dash somewhere for now.

Last night I worked on some more engine compartment wiring. I mounted a ground block under the battery tray. I also wired up the fan to a relay there. I had to then run a wire from the relay across the core support to the bulkhead wiring for the fan controller. Instead of running it through a hole in the firewall I decided to put terminals on each end and use open slots in the bulkhead connector. I did the same thing for the Dakota Digital sensor wiring. All time consuming!

I dug around and found a random aluminum bracket to mount the controller too. Id like to make it semi-accessible for adjustments and being able to see the display incase I need to. So I found a spot next to the steering column. It'll make all my connections short, neat, etc.

wiring it should be quick now. Just connect the relay wire, the temp sensor wiring, 2 12v wires and a ground. I'm not hooking up the optional AC wire for now. Ill see how the fan does and add it if necessary. I may just add a manual toggle switch to that wire to turn the fan on and off.
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