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Old 06-04-2019, 06:50 PM   #26
jojo-munson
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Re: Greenie the 72 C20

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Originally Posted by cornerstone View Post
You’ve got quite the fan club there! Fang has the biggest tongue I think I’ve ever seen. One lick from him and you’d need a beach towel to dry off! Great (dane) picture man!
With the way he was panting and the windows open, it felt like there was a light rain (of drool) in the cab for the entire trip. At least it kept me cool!
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Old 06-04-2019, 07:28 PM   #27
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Re: Greenie the 72 C20

Something has just felt off about the way the engine has been idling, so I started poking around (Getting 7 mpg was a motivator too, that really hurts at the pump). Checked my carb manual and realized a fuel pressure of 6.5 psi was too high, so changed it to the recommended 5.5 psi. Also played with the idle mixture screws following Edelbrocks tuning guide. Only issue with that is that my idle speed moves up and down all on its own by about 50 rpm, but I did my best. Checked Vacuum, and it's a nice steady 15 ish.

Figured out the main component of my oil leak, was me not tightening the drain nut in the pan enough.. Doh!

But a second component to the oil leak was from spark plugs on the passenger side. Numbers 8 and 6 wires were wet with oil, and it was dripping down the engine. That was weird I thought, so I pulled the plugs. Number 8 was barely even hand tight, I wouldn't have needed a wrench at all to get it out. The rest of the spark plugs were tighter.

You can see in the pic below, #8 was reeeaaal bad. These are Delco r44lts plugs by the way. I'm hoping that I just hadn't tightened that plug enough originally, so there was sub-par compression and oil was leaking out around it.

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I replaced all the spark plugs (and wires too for good measure), store didn't have the r44's so I used a different type, some platinum's of a brand I can't remember. The new plugs are the same length, but the threads are only half as long, so the plugs only screw in half as far. So that's odd, but the truck fired right up. Only I had to increase the idle speed by about 300-400 Other than that it sounds the same, no change.
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Old 06-29-2019, 09:15 PM   #28
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Re: Greenie the 72 C20

Found out from my grandpa that the shocks are original. This info along with the bouncy ride influenced me to buy some new ones. KYB 344068 and KYB 344085.

Pretty easy to install. Didn’t need to take the tires off or lift the truck. Only trouble was the passenger side frame bolt. The metal gas line was routed directly on top of the nut.

The old shocks were junk, you could get pull/push them any length and they’d stay that length. The new ride quality is definitely better. Not like a shiny new sports car mind you, but definitely an improvement.

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Old 06-29-2019, 09:23 PM   #29
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Re: Greenie the 72 C20

Got tired of looking at the rusty ole wheels so I decided to paint them. Spray paint is cheap so if I don’t like the color no big loss. I got rustoleum paint/primer in one metallic aged copper.

The can itself sucked. It would only spray upside down, and even then it came in spurts. The picture is after 2 coats and about 30 min of dry time. It’s shinier than I want, so hopefully it’ll dim down once it’s completely dry.
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Old 06-29-2019, 11:09 PM   #30
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Re: Greenie the 72 C20

Great looking truck and story! We share a very similar truck, story of how we acquired it, general location, and I even replaced all the suspension parts about 2 weeks ago. Not sure if you're back on the west side but I am down in Sumner. Will differently keep an eye on this build and an eye out for the truck.

One thing you may want to look into is registering your truck as a collectors vehicle. I did this and put on era-specific plates and replica '71 truck tabs. Now, I do not have to renew tabs ever again. It has loose language on how you can use the truck.

"May be driven: To and from auto shows, circuses, parades, displays, special excursions, and antique car club meetings. For testing purposes. For the pleasure of others without compensation."

I drive and use mine for all sorts of things from random daily driving/ dump runs/ etc and if I was ever stopped I would site the above text from the DOL and said I am driving it for the pleasure of others without compensation. I have a coworker with collector plates on his true daily driver (old ford truck) and he has never had an issue with it. Anyways, just wanted to pass along the info if you want to get it looking more era-specific or just add a cool factor from when your grandpa drove it.
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Old 06-30-2019, 11:34 AM   #31
Jonny Hotnuts
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Re: Greenie the 72 C20

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Originally Posted by jojo-munson View Post

But a second component to the oil leak was from spark plugs on the passenger side. Numbers 8 and 6 wires were wet with oil, and it was dripping down the engine. That was weird I thought, so I pulled the plugs. Number 8 was barely even hand tight, I wouldn't have needed a wrench at all to get it out. The rest of the spark plugs were tighter.

You can see in the pic below, #8 was reeeaaal bad. These are Delco r44lts plugs by the way. I'm hoping that I just hadn't tightened that plug enough originally, so there was sub-par compression and oil was leaking out around it.

That plug is oil fouled. Oil in the cylinder is not caused by insufficient torque on the plug seat. You have a broken ring land on the piston, bad scraper ring, bad valve seal or other issue. A leakdown test should point out what is the issue.

Also....


Its a bad idea to run shorter plugs than the head is designed for. If this was a high performance engine you could get detonation due to hot spots from the exposed threads (*ok, not really a factor here but....). It will also gum up or damage the exposed threads, will LOWER compression ratio and wont run well.

If I had to guess Id wager all of the problems you are having with this motor would be solved if the heads were rebuilt....but new spark plugs will NEVER solve what caused #8 to look like that.

My advice is to get or borrow a leakdown tester and find out if the oil is coming from the bottom or the top and fix the reason oil is getting in the hole.

~JH
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Old 06-30-2019, 09:48 PM   #32
jojo-munson
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Re: Greenie the 72 C20

Quote:
Originally Posted by bozly View Post
Great looking truck and story! We share a very similar truck, story of how we acquired it, general location, and I even replaced all the suspension parts about 2 weeks ago. Not sure if you're back on the west side but I am down in Sumner. Will differently keep an eye on this build and an eye out for the truck.

One thing you may want to look into is registering your truck as a collectors vehicle. I did this and put on era-specific plates and replica '71 truck tabs. Now, I do not have to renew tabs ever again. It has loose language on how you can use the truck.

"May be driven: To and from auto shows, circuses, parades, displays, special excursions, and antique car club meetings. For testing purposes. For the pleasure of others without compensation."

I drive and use mine for all sorts of things from random daily driving/ dump runs/ etc and if I was ever stopped I would site the above text from the DOL and said I am driving it for the pleasure of others without compensation. I have a coworker with collector plates on his true daily driver (old ford truck) and he has never had an issue with it. Anyways, just wanted to pass along the info if you want to get it looking more era-specific or just add a cool factor from when your grandpa drove it.

I'm in Pullman for now, but I pop over there every now and then to see family. That's great advice about the plates! I'll have to look into that a bit more. I wonder if it would change my insurance.
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Old 06-30-2019, 09:57 PM   #33
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Re: Greenie the 72 C20

Quote:
Originally Posted by Jonny Hotnuts View Post
That plug is oil fouled. Oil in the cylinder is not caused by insufficient torque on the plug seat. You have a broken ring land on the piston, bad scraper ring, bad valve seal or other issue. A leakdown test should point out what is the issue.

Also....


Its a bad idea to run shorter plugs than the head is designed for. If this was a high performance engine you could get detonation due to hot spots from the exposed threads (*ok, not really a factor here but....). It will also gum up or damage the exposed threads, will LOWER compression ratio and wont run well.

If I had to guess Id wager all of the problems you are having with this motor would be solved if the heads were rebuilt....but new spark plugs will NEVER solve what caused #8 to look like that.

My advice is to get or borrow a leakdown tester and find out if the oil is coming from the bottom or the top and fix the reason oil is getting in the hole.

~JH
I didn't realize that running the shorter plug could damage the threads, but that makes total sense. I'll have to go get a different set.

Hmm I bought the heads brand new and had a machine shop assemble them so it would suck if they were the problem, but it's definitely a possibility. I could definitely see it being a piston ring though. Thank's for the input! I'll have to find a leakdown tester then
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Old 07-06-2019, 03:55 PM   #34
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Re: Greenie the 72 C20

Nice truck.
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Old 09-26-2019, 11:42 PM   #35
jojo-munson
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Re: Greenie the 72 C20

The good:

Figured out where the leak into cylinder 8 was coming from. The intake manifold! I'm guessing that "pop" I heard a while ago was the gasket coming up a bit. Replaced the intake gaskets and cylinder 8 plug is nice and dry with no build up now. Woo!

Horn started honking whenever I used the blinker on left turns, so I replaced the turn signal switch. Maaaan is the turn signal so much smoother now. Plus it actually clicks itself off! Wish I would have done this when I first got the truck.

Replaced the steering wheel with a Grant 313 wheel. Not super impressed with it, but oh well. Plans are to repair the original wheel at some point, but so far I like having a smaller diameter wheel.

The bad:

Did a compression test for the first time. Almost all cylinders were about 110-120. Except #8, which had a compression of 95. So not great, but based off my googling, not the end of the world for now. Hopefully in the next year or so I'll make enough money to either re-build it or swap it.
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Old 09-28-2019, 03:31 PM   #36
68Gold/white
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Re: Greenie the 72 C20

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Originally Posted by jojo-munson View Post
I didn't realize that running the shorter plug could damage the threads, but that makes total sense. I'll have to go get a different set.

Hmm I bought the heads brand new and had a machine shop assemble them so it would suck if they were the problem, but it's definitely a possibility. I could definitely see it being a piston ring though. Thank's for the input! I'll have to find a leakdown tester then
My knowledge of Vortec stuff is zero. Johnny is correct about switching to the plugs you used....I'm sure Vortec and even later stuff all use different plugs than the oldies used...

One issue is that to get the AC plug for a Vortec head, they usually only offer them in the super-de-duper version in AC. Get a set of Autolite plugs, just plain plugs, nothing fancy. SHould be $1.50-$2.00 each at most.

You might try pouring some auto trans fluid in that cyl and let it set for a while, to see if it could be a stuck ring. There are many products made to do this job that are more expensive. Just make sure you turn the engine over several rotations to pump all the trans fluid out before running engine again. It will be messy...

Carry On!!!
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Old 09-28-2019, 08:04 PM   #37
jojo-munson
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Re: Greenie the 72 C20

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Originally Posted by 68Gold/white View Post
You might try pouring some auto trans fluid in that cyl and let it set for a while, to see if it could be a stuck ring. There are many products made to do this job that are more expensive. Just make sure you turn the engine over several rotations to pump all the trans fluid out before running engine again. It will be messy...

Carry On!!!
I'll have to give that shot, sounds like an easy thing to try.

Looking at spark plugs I'm probably going to go with a set of AC Delco R44LTS6. Pretty much the same price as the Autolites at O'Reilly's. When I first swapped the Vortec heads I used R44LTS plugs, which are pretty much the same as the R44LTS6 plugs except the R44LTS have Platinum tips and a 0.044 inch gap; whereas the R44LTS6 have Nickel tips and a 0.059 inch gap.

They're priced the same, but the R44LTS6 are the ones in stock.
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Old 06-11-2020, 06:20 PM   #38
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Re: Greenie the 72 C20

Since my last post I’ve graduated, moved across the country, and started a career. Buying a house too, so soon the truck will have a spot in a garage!

Due to all those shenanigans not much has been done on the truck. I did make a magnetic faceplate to cover the ashtray hole. Just some scrap wood and magnets glued into the back.
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