What have you done to your square lately??

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smurph20

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Clyde, Arkansas 72717
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Brad
Truck Year
1986
Truck Model
K20
Engine Size
350/SM465/NP208/4.10's
Sounds like a bit tired motor. When motors get to this point, this is where I normally like to pull it and do a poor man rebuild. Rings, Bearings, Timing Set, Gaskets, and a Valve Job if you can afford it, or lap the valves yourself and replace the seals. Put it all back together and should be good for 75,000-100,000 miles depending on it's current condition. After that, it's without a doubt, time for a new bore, pistons and complete Valve Job and complete with rebuild with crank turn, resurfacing, balanced etc.

Ive got a deal worked with a guy at work 4 bolt main short block with about 10,000 miles. I also am getting that early vortec motor for 35 bucks. So with the vortec heads cleaned with new seals on the 4 bolt main block with a Performer intake and a 650 Holley and headers I should be good to go for awhile.
 

HotRodPC

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Silverado
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454 - Turbo 400 - 3.73
Ive got a deal worked with a guy at work 4 bolt main short block with about 10,000 miles. I also am getting that early vortec motor for 35 bucks. So with the vortec heads cleaned with new seals on the 4 bolt main block with a Performer intake and a 650 Holley and headers I should be good to go for awhile.

:waytogo:

Don't trash that motor though, unless you have no intent of going to back to old school ever. I'd imagine you have a virgin 350 now huh? Or even if it's been bored already, it'd have .030, .040 or .060 pistons in it and those pisons can be reused on a virgin block and bore it to whatever those pistons are with new rings and it's as good as a new motor. Piston skirts might wear a little, but past that, it's the rings and the bore that gets the most wear and pistons can be reused over and over and over until the wrist pins give up from being pressed off and on to many times. :imo:
 

smurph20

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:waytogo:

Don't trash that motor though, unless you have no intent of going to back to old school ever. I'd imagine you have a virgin 350 now huh? Or even if it's been bored already, it'd have .030, .040 or .060 pistons in it and those pisons can be reused on a virgin block and bore it to whatever those pistons are with new rings and it's as good as a new motor. Piston skirts might wear a little, but past that, it's the rings and the bore that gets the most wear and pistons can be reused over and over and over until the wrist pins give up from being pressed off and on to many times. :imo:

Well my truck is an 86 and according to the serial number on the block it is a around 75-78 model so as far as virgin I doubt it but I am going to hang onto it.
 

HotRodPC

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454 - Turbo 400 - 3.73
Well my truck is an 86 and according to the serial number on the block it is a around 75-78 model so as far as virgin I doubt it but I am going to hang onto it.

Yeah, you'd think it's been rebuilt by now. But that's good. That would mean it has oversize pistons in it. I hate the fact I'm scrapping a virgin never been cracked open 74 350 out of an El Camion with this bent frame and burnt cab. I have to 2 other 350 motor cores that have not set out in the weather for over 20 years and figured I'd want to get into an LS swap at some point, so I've got enough motors for now. And being that noone really wants to deal with a rusted and seized 350, I'd get as much or more from scrapping it as selling it at $11.25 per 100lbs so I decided to scrap it.
 

bucket

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GTME94

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Metro Detroit/Holland, MI
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Terry
Truck Year
86
Truck Model
C2500 C6P Camper Special
Engine Size
454/TH400/14bff 3.73
Adjusted my choke some more. It was idling too high and the choke wasn't pulling off. Now it seems good. Also got some vacuum hose and a heat stove pipe and hooked up the exhaust heat flapper door in the air cleaner. The flapper door works when cold, didn't get a chance to get it fully warmed up to see if the thermal valve turns off or not. But with as much cold as we've had and as little as I drive the truck in winter, it can stay on full time for now. I may disconnect the vacuum hose in spring/summer anyway.
 

skysurfer

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The flapper door works when cold, didn't get a chance to get it fully warmed up to see if the thermal valve turns off or not.

Easy to check the flapper door operation by aiming a hair dryer up into the stove pipe inlet. Usually just takes a minute or two to see movement in the snorkel.
 

SlickGTP

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Houston, TX
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1973
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C10
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454
Finally got all the scale, dirt, and grime off the frame and por15'ed the frame from the firewall back... :jawdrop:

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She's looking perttier... Can't wait to get the cab back down on the frame and the exhaust on 'er. Then it's time to get the bed back together. :driver:
 

GTME94

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Terry
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86
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C2500 C6P Camper Special
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454/TH400/14bff 3.73
Easy to check the flapper door operation by aiming a hair dryer up into the stove pipe inlet. Usually just takes a minute or two to see movement in the snorkel.

That's a great idea! I'll try that next time I'm over at my truck.
 

HotRodPC

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HotRod
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85 K20 LWB
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Silverado
Engine Size
454 - Turbo 400 - 3.73
Finally got all the scale, dirt, and grime off the frame and por15'ed the frame from the firewall back... :jawdrop:

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She's looking perttier... Can't wait to get the cab back down on the frame and the exhaust on 'er. Then it's time to get the bed back together. :driver:

Sprayed or Brushed?
 

HotRodPC

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HotRod
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85 K20 LWB
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Silverado
Engine Size
454 - Turbo 400 - 3.73
Finally got all the scale, dirt, and grime off the frame and por15'ed the frame from the firewall back... :jawdrop:

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She's looking perttier... Can't wait to get the cab back down on the frame and the exhaust on 'er. Then it's time to get the bed back together. :driver:

This is the factory 73 C10 2wd Frame that the truck came with originally.
 

SlickGTP

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C10
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454
Rolled and brushed...

Yup... She was basically all original when I picked it up. That's one heavy duty frame for a half ton too. Under each of the spring hangers there's bracket that goes from the underside of the frame to the hanger. Never saw that before this one.
 

89Suburban

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Great job!
 

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