New For Me 1985 Silverado 20 6.2 Diesel

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Craig Nedrow

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Craig
Truck Year
1973 (have two), 1985
Truck Model
K10, K20, C20
Engine Size
350, 454, 6.2 Detroit
Well that didn’t work. Didn’t leave me stranded, but had to cool down then started. Soooo got a solenoid will wire it in with a starter button to manually toggel the glow plugs. I hope to install tomorrow. Got more parts, mostly oil maintenance, engine oil and filter, done today, got the rear end gasket, so can change the fluid, have the fluid. Also got a new trans filter, so that completes all the fluids changes. Like the truck, been driving it everywhere, but don’t shut it off. Dogs dig it, head out the window, life is pretty good. Ps the mileage is great, keeping track curious about the mpg.
 

CountKrunk

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Count
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1984
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C20 Custom Deluxe 3+3
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v8 350
i did the same, don't turn it off when I was making the trip from GA to VA. Didn't crank back up halfway there, banged on the starter and that got it. Got gas every hourish lol (fuel gauge is broken).
 

Craig Nedrow

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Engine Size
350, 454, 6.2 Detroit
Worked all day on the manually operated glow plug switch. The dash was full of air conditioning tubes. Lots of head scratching, finally settled on the Johnny Armstrong method. No parts or persons injured. I will do a pictorial tomorrow. Also changed the oil and filter, have the rearing gasket and oil. Also changing the trans filter, and oil. Only thing left since I just replaced the radiator will be the wheel bearings, and allows me to check the brakes. Going in-for an alignment tomorrow Wed, town day.
 

Craig Nedrow

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Engine Size
350, 454, 6.2 Detroit
As promised Manual glow plug parts and instillation for 1985-90's diesels. Parts used, push button switch, solenoid, 1/4 spade. mounted switch where there was an existing 1/2 inch hole, but had to open it up to 5/8 using a stepped bit. Once the location was determined, using a sharp 1/8 ex screwdriver, pushed a hole through from the engine side as easier to get to. Used 14ga wire, pushed it through the mastic and into the cab. This wire will eventually go to the solenoid from either terminal on the switch. Attached another 14ga red wire to the 1/4 spade, which will go on the top right side of the fuse box to the AUX slot, which has current with key on only.
 

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Craig Nedrow

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1973 (have two), 1985
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K10, K20, C20
Engine Size
350, 454, 6.2 Detroit
The keyed power from the fuse box is attached to the other switch terminal. I routed the wires over the brake assembly to keep the wires out of sight, and for protection. checked the switch for power B-4 proceeding to the engine compartment.
 

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Craig Nedrow

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1973 (have two), 1985
Truck Model
K10, K20, C20
Engine Size
350, 454, 6.2 Detroit
I mounted the solenoid here as there was already a bolt there, just bolted it down. Remove the two bolts holding the original glow plug controller, (unhook battery terminals first from both pos side of the batt, and neg of main battery.) Remove all wires from controller and set the controller aside, it will not be used. Power from batt on big left terminal. power to L&R bank glow plugs on right terminal. On my truck the glow plug wires start out black, go through a fusible link?, then the familiar 10-12 ga orange wires. I used the existing terminals that were already there, simply bolted them up as above. The red power from cab is attached to the left middle small terminal. I pulled the wire out from the cab to take up the slack, then checked under the dash to see if it needed routing , and adj. Used one zip tie under dash. Routed the wire as shown, cut to length, installed appropriate size ring terminal, crimp, (I use a Kline crimper, buy once, cry once, great tool,) install. Tucked the original controller wires as in picture, original controller not used.
 

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Craig Nedrow

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K10, K20, C20
Engine Size
350, 454, 6.2 Detroit
Starting procedure is. 1) turn key on, 2) push glow plug button for the appropriate amount of time determined by you, 3) and start. While this took more then a day, I believe this is the least invasive, neatest, easiest method using as much of the existing wiring as possible. While I was at it, I replaced the toggle switch with the one I bought at Rock auto, and installed, works and looks as it should, hated the toggle droopin' out the hole, but it did work. Next up is replacing the rearend gasket and oil, and the trans pan gasket an oil, oil coming...waiting for the alternator and p-steering belts to get here so I can install all three, (have A/C belt) at the same time. Gotta get ready for fishing soon, the Coho will be running, and hope to spend a week fishing on the Columbia and Klickitat rivers. Hope this will be helpful for future reference for everyone having to deal with the finnicky original system.
 

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Craig Nedrow

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Truck Model
K10, K20, C20
Engine Size
350, 454, 6.2 Detroit
To town today and the C20 alignment, drives nice, but need tires. Question, My courtesy lights and horn do not work. Door switches toast so they are coming. HOWEVER after pulling off the kick panel cover by the vent, there is still no access. Does the switch just turn out? Help appreciated. Tires next, Ugg$$$
 

Craig Nedrow

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Engine Size
350, 454, 6.2 Detroit
Alignment done, new tires on, smooth and goes down the road so nice. Mileage is about 24.5 mpg. Serviced the trans and rearend, parts from rock auto, everything fit. Will pack front wheel bearings and that completes the service on the C20. Few pic up on the rack, you can see how nice that raptor liner is. Think she is ready for a fishing trip on the Columbia and Klickitat river.....
 

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Strick

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C20 Crew
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350
To town today and the C20 alignment, drives nice, but need tires. Question, My courtesy lights and horn do not work. Door switches toast so they are coming. HOWEVER after pulling off the kick panel cover by the vent, there is still no access. Does the switch just turn out? Help appreciated. Tires next, Ugg$$$
The switches thread into the door jamb. Just unscrew them but be prepared to have a broken wire when finished as they will sometimes twist into.

HS
 

Craig Nedrow

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Truck Model
K10, K20, C20
Engine Size
350, 454, 6.2 Detroit
The switches thread into the door jamb. Just unscrew them but be prepared to have a broken wire when finished as they will sometimes twist into.

HS
That's what I suspected, thanks brother, this is why I love it here.
 

Blue Ox

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MCMLXXXV
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The switches thread into the door jamb. Just unscrew them but be prepared to have a broken wire when finished as they will sometimes twist into.

HS

Hold the pin while you're unscrewing the sleeve so it doesn't wind up the wires.

WD-40 is your friend.
 

Ricko1966

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c20
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350
Alignment done, new tires on, smooth and goes down the road so nice. Mileage is about 24.5 mpg. Serviced the trans and rearend, parts from rock auto, everything fit. Will pack front wheel bearings and that completes the service on the C20. Few pic up on the rack, you can see how nice that raptor liner is. Think she is ready for a fishing trip on the Columbia and Klickitat river.....
That's what I love about the 6.2 unbelievable MPGs only checked my milage once that was on the trip home from buying it and after I got it home . I got 25 couldn't believe it.
 
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Craig Nedrow

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Craig
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1973 (have two), 1985
Truck Model
K10, K20, C20
Engine Size
350, 454, 6.2 Detroit
That's what I love about the 6.2 unbelievable MPGs only checked my milage once that was on the trip home from buying it and after I got it home . I got 25 couldn't believe it.
Fill up both tanks, could almost drive to your house with out stopping for fuel. In any case thank god for Indian reservations, and the cheap(er) fuel.
 

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