69 GMC C-15

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DoubleDingo

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1981
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81-C20 Silverado Camper Special-TH400-4.10s
Engine Size
Carb'ed Vortec 350
I think my tires were 30.7 diameter, and with the 3.54's it ran 70 mph at 2,600 rpms. For some reason that engine loved 3,000 rpms which put cruising at 80 and higher.
 

TravisB

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I had been banking on my cousin giving this old truck a buff job and shining it up for the car show at the end of the month. I found out Saturday that wasn't going to happen. I have 0 experience but with as bad as the paint was I have wet sanded it with 2500 grit and got most the color even. I ordered a DA buffer and some compounds from chemical guys thanks to their handy videos on how to do this job and I hope I can make the thing shine again.

I also need to rebuild the carb because it's started flooding when it's hot and fuel comes out both sides of the old Rochester 2 jet. I have a rebuild kit that should be here before the weekend and a buffer on the way. What a nightmare.

Also, meeting a friend that works for Holley to tune that sniper on the Corvette this weekend so it will be an after work special to try and wrap this one up before next Saturday. We don't even have the sniper wired or the accessories going on that Vette. Not enough time in my days anymore.
 

TravisB

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This is the rebuild kit for the carb. Looks like a bunch of universal stuff in here. Loose clips and check balls too. This could be a real treat :help:

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I did wash the whole truck last night and ran a clay bar over the top since the white has held up much better than the teal or turquoise this truck was painted. Hopefully the buffer gets here today and I can make it look half way decent.

What do you guys recommend for bringing the shine back to old chrome?
 

DoubleDingo

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1981
Truck Model
81-C20 Silverado Camper Special-TH400-4.10s
Engine Size
Carb'ed Vortec 350
Rebuilding a carb isn't too bad. Just have to make sure you match the gaskets and other parts when there are extras in the kit.

I just use chrome polish to polish the chrome on my rigs. Seems to work okay, but the chrome isn't crazy bad on them. Shines up nicely. I need to clay bar Crusty Biscuit, it looks good after a wax, I can only imagine what running a clay bar over it would do with a waxing involved afterwards.
 

CSFJ

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This thing has a 307 v8 and a th400 transmission. I can't imagine why the 400 when it didn't even get a bumper you could tow from or a long box either. Small engine, no tow capability, needs the heavy trans clearly. Lol
I may be wrong, but I seem to recall hearing/reading that the th400 was developed before th350 was. Not sure on the year for the th350, iirc the th400 first showed up around '64. The other possibility, is that all the auto equipped trucks got the th400 regardless. I know the auto 'vettes all got the th400 until the big block option went away in '75.
 

DoubleDingo

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Engine Size
Carb'ed Vortec 350
My '63 Shop Manual shows the automatic as a Powerglide. Now you got me curious. I now need to look at my '65 Supplement, and my '68 Shop Manual. I know in '68 the C20 Suburban's got the 396/TH400/Dana 60 (3.54) setup.
 

TravisB

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Rebuilding a carb isn't too bad. Just have to make sure you match the gaskets and other parts when there are extras in the kit.

I just use chrome polish to polish the chrome on my rigs. Seems to work okay, but the chrome isn't crazy bad on them. Shines up nicely. I need to clay bar Crusty Biscuit, it looks good after a wax, I can only imagine what running a clay bar over it would do with a waxing involved afterwards.
I have washed this thing, clay barred it, wet sanded it with 2500, and now made one pass over it with a DA buffer + orange medium cutting pad + V34 from the chemical guys. It looks better than it ever has while I have owned it. If I follow their path, I am supposed to buff over that with V36 and then another round with V38 before finally wax and sealer.

That will have to be a job for tomorrow. Waiting on my 2 buffer pads to dry out after washing out the polish. I have 9 days left if I count show day to finish. The carb is still on the truck for now.

This is my attempt to show how the front half of the hood is buffed with the first round and the rest isn't. Crappy pic though.

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The rest of these are all after the buff job with their v34.

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DoubleDingo

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Carb'ed Vortec 350
Looks good so far!
 

DoubleDingo

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Carb'ed Vortec 350
Here's the transmission stuff...

1963...
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1965....
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1968...
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75Monza

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I finished changing the fuel pump last night and jumped it off so I could see if I had it right. Everything went well. Took it for a spin down the drive and back and all seems well. Now to see if I can find out where there transmission leak is coming from and get a battery. Then we get into the not so necessary things like figuring out why the fuel gauge doesn't work, why the heater fan doesn't work, shining it up, and getting the seat re-covered.

I will snap some pics from underneath when I get it on the lift so you all can see the underside too!
When I got my 71, had a bad connection on the sender at the tank is why my gauge didn't work. Probably from storing stuff behind the seat. I bought the carpet kit that covers over the whole tank area behind the seat to stop that from happening again. On the heater, is it the actual fan that doesn't run? I had corroded connections at the switch and the resistor that I had to clean and then one of the slide levers was bent and would hit the switch in one direction so only had roughly two speeds. Can also have a bad ground on it too.
 

bucket

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Iirc, the TH400 debuted late in the '65 model year, along with the '65 Caprice. I don't think the TH350 was used before '69.
 

TravisB

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When I got my 71, had a bad connection on the sender at the tank is why my gauge didn't work. Probably from storing stuff behind the seat. I bought the carpet kit that covers over the whole tank area behind the seat to stop that from happening again. On the heater, is it the actual fan that doesn't run? I had corroded connections at the switch and the resistor that I had to clean and then one of the slide levers was bent and would hit the switch in one direction so only had roughly two speeds. Can also have a bad ground on it too.
Those have been on the to do list for a while. I've been busy working on the 78 and neglected this one. I'll hopefully get around tho those soon. I'll keep this in mind when I do. Thanks!
 

TravisB

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Well I went ahead and pulled the carb off. Tore it down and have half of it soaking in parts cleaner and will have to work the other half in after. Got one of those gallon of gunk parts cleaner with the little basket inside. We'll see how that works.

It has a pair of 52s inside if anyone was curious. Looks like it was full of some rust and crud. My little sandstone filter isn't cutting it or that's just 50 years of collected sediment.
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TravisB

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After a bath in the cleaning solution and a little air blast. Does anyone elses work bench look like a filthy mess of clutter? Hahahah

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TravisB

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C10
Engine Size
350
Good news gang! I put the carb back together, no left over bits to throw away outside of some extra gaskets and junk from the kit! Even better news, the carb is back on the truck, it started, and with a bit of monkeying with the idle air screws and the idle speed it's holding almost 17-19in-hg. No flooding anymore and it will start hot again!

I should give credit to this guy for my success. I watched this video once on the tear down.
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Then I watched this video on putting it back together twice before I ever took mine apart and then watched it while pausing in places putting mine together.
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My carb isn't the electric choke model but it was nearly identical otherwise. My choke was activated from within the intake somehow. There is a rod coming up from the intake that works mine around. I assume some temperature spring that flexes when the engine is cold.

Now all I think I am going to do is polish the chrome and give everything a top coat sealant and wax and call it quits.
 
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