Carb adjustments

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Sundawg3
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Carb adjustments

Unread post by Sundawg3 » November 20th, 2023, 8:40 pm

Gentlemen,

The Mutt, I was told and it appears so, had a complete overhaul of the engine, transmission, transfer case, and differentials. It kinda ran a little crappy and the exhaust manifold is almost red. I'm guessing it was lean but don't know if that was before or after the overhaul? I turned the mixture screw clockwise or in and it started to run smoother. Adjusted the idle down quite a bit too. It idles and runs great except a little doggy in first and second when first starting out. Third and fourth punching the peddle runs great. I believe the carb is a Zenith. Any words of wisdom on proper settings for the mixture screw? What should this idle at? Not that I have a tach but it sounded around 1000 RPM before and would grind going into first. Now it slides right in. Don't want to run it lean but also don't know how to properly check without removing the plugs every so often and doing the old fashioned one eye open look see.

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rickf
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Re: Carb adjustments

Unread post by rickf » November 20th, 2023, 11:12 pm

Ok, you are getting way ahead of yourself here! Here is one of the few stickies we have here on this forum for people to read.

viewtopic.php?t=2395

You need to get hold of the manuals for this vehicle. I have them on here and will be posting them soon but since I just took ownership of the forum I need to get some stuff in order. You can download the manuals from Pedro's.cz for now. You will need the tm 9-2320-218-10, -20-and -34 right off the bat and the parts manuals -20P and -34P.
But before you go playing around with the carb too much you need to check the points if it has them, the timing, the valve adjustment. Then and only then can you adjust the carburetor.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

Sundawg3
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Re: Carb adjustments

Unread post by Sundawg3 » November 20th, 2023, 11:30 pm

Thanks Rickf,

I had read that sticky but figured since the engine and all drive terrain were freshly overhauled the carb should have been set "close" to normal?? I would guess by a pro. It's been sitting for some time so I figured crappy old fuel. Had a blast running that out and filling with new. I'll take a look at your list and run with it. I've been on Pedro's site since he provides good information. I am having trouble understanding the governments labeling of vehicles, part numbers, and technical manuals as to which goes to what vehicle. Guess I'll have to dumb down a lot so it'll make sense.

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rickf
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Re: Carb adjustments

Unread post by rickf » November 21st, 2023, 9:54 am

When you say the engine and drivetrain were freshly overhauled, where did you get that info? Who did it and when? And what was done to the components as far as "Overhaul"? An "overhaul" can be anything from pulling out the powerpak and pressure washing it and putting it back in and calling it good to tearing it all down and replacing all of the wear items with new parts all set to spec. Or anything in between. If you did not get paperwork proving what was done and when then consider nothing was done and work from there. That is the safest and easiest way to get a vehicle that has been setting a long time going. As far as the manuals, everything you need to know is in there, but I will admit it can be a chore to find. The -20 manual will have everything in it that you are needing as far as general repair work. The -34 manual is for major repairing of individual components like the engine or differential or transmission. The -10 should be read before you even drive the vehicle, I think you are past that point but you really do need to read it.
You are no different than anybody else who buys a new toy. They want to play with it right away. The problem is that if you do not find the problems areas before driving they will come back to bite you later and they will be expensive. Perfect example is the engine, I have seen so many people bend pushrods in these because they want to go right out and try to start it before taking the valve cover off and making sure the valves are all free and adding a bit of lube to each one. They just start cranking and those stuck valves bend the pushrods into bananas. Or if you are lucky they just pop out. But grease gets old and dries out in axles and u-joints. These u-joints are 151 specific, you cannot get them in the civilian world. I know the internet will tell you that such and such joint will fit for the axle joints bit it is not the right joint. It will fit but the cross is just a few thousandths shorter so it can move side to side. What I am saying is you need to preserve these parts since eventually they will be gone.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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m3a1
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Re: Carb adjustments

Unread post by m3a1 » November 22nd, 2023, 11:42 am

Or, as I like to say...

Show it some love. You DO want the Show It Some Love achievement badge, don'tcha?

Sundawg3
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Re: Carb adjustments

Unread post by Sundawg3 » November 24th, 2023, 10:27 pm

What the hell is that?

Mark
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Re: Carb adjustments

Unread post by Mark » November 24th, 2023, 10:47 pm

MONEY!!
mark


1968 m274A5
1960 m151
1981 m151A2
1964 m416
1971 m416

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Horst
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Re: Carb adjustments

Unread post by Horst » November 25th, 2023, 8:05 am

I agree on the overhaul comment. Most of the overhauls I have seen were fresh paint. Certainly the army did overhaul engines and transmissions but overhauling a transmission today will be a very expensive exercise. I believe repairing an engine or transmission as needed is more adequate.

Have we already seen pictures of your 151?
Horst

1972 USMC M151A2 w/ROPS (ex Barstow) and M416
1962 M201 and trailer
1966 GTO,1982 E350 Skoolie, 1987 SJ413, 1987 911
Gone: 2xM35A2c, Unimog 404S, Hanomag AL28, DKW Munga

Sundawg3
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Re: Carb adjustments

Unread post by Sundawg3 » November 25th, 2023, 11:19 pm

I'm no military vehicle expert but I have been around aircraft and cars for well over 30 years. This one is nice and the previous owner spent a considerable amount on it. I was told it was owned by a judge who purchased it from the government and it sat in his barn until he sold it, in 2011, to the family I purchased it from. This person started rebuilding it then and mostly finished until he passed last winter. I acquired it from the estate. I have proof of the previous owners and the story fits. The engine and transmission were either completely overhauled or at least rebuilt. I didn't receive records with the purchase. The differentials I don't believe have been touched except flush and fill. I've spent the last several weeks fixing minor things and tightening bolts either rattled loose or weren't torqued. I've replaced some gauges, drive train bolts, a bunch of hardware, and cleaning up the engine compartment. Still have more to do. Yesterday I installed 700X16 Firestone military tires, tubes and flaps. That was a learning experience. Myself and the guys at the tire shop looked like a bunch of monkeys with a football! An old guy, that recently retired walked in, (thank God) and asked what the F we were doing. He educated the entire shop and made us all feel stupid rather quickly. What took three of us an hour (one tire) he finished the other four in the same time. He did say he hasn't done military tires in over 20 years. The body has three dime sized rust holes in the cross supports under the body where the drivers and passengers feet are. That's the only rust I can find. The only mod I see are the seat belts and the top is aftermarket. The battery compartment looks almost new as does the tool compartment. No rust or corrosion. It has a complete M60 mount which looks to be an original installation. The M151 was originally green with what looks like FS30372 sand paint, the engine compartment is slightly different but close to the sand color. This project has been a blast but it's been a long time since I drove a vehicle for 30 minutes and worked on it for four hours after. Pics added Horst.
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Sundawg3
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Re: Carb adjustments

Unread post by Sundawg3 » November 25th, 2023, 11:53 pm

About $3,000.00 and counting Mark. Is that LOVE?

Mark
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Re: Carb adjustments

Unread post by Mark » November 26th, 2023, 2:14 am

Yes, with a price tag! Beauty is part of it!! But there are several parts to it. You are making it a work of art.One people will remember.
mark


1968 m274A5
1960 m151
1981 m151A2
1964 m416
1971 m416

Mark
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Re: Carb adjustments

Unread post by Mark » November 26th, 2023, 2:15 am

I like your answer.
mark


1968 m274A5
1960 m151
1981 m151A2
1964 m416
1971 m416

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FoxMike
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Re: Carb adjustments

Unread post by FoxMike » November 26th, 2023, 2:29 am

Nice looking jeep. The bumper markings have it made out to be the 181st Fighter Wing out of Terre Haute, IN.
M151A2 AMG
1952 M38A1 sold.

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Horst
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Re: Carb adjustments

Unread post by Horst » November 26th, 2023, 2:50 am

Thanks for the pictures. That little jeep looks awesome
Horst

1972 USMC M151A2 w/ROPS (ex Barstow) and M416
1962 M201 and trailer
1966 GTO,1982 E350 Skoolie, 1987 SJ413, 1987 911
Gone: 2xM35A2c, Unimog 404S, Hanomag AL28, DKW Munga

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rickf
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Re: Carb adjustments

Unread post by rickf » November 26th, 2023, 9:14 am

Nice looking 151. The carb on there is a last contract 13660 actually made in Thailand under contract to Zenith. So it is exactly the same carb as the 13660 but with a different number. I have been running one on mine for at least the last ten years. If it was sitting for a long period then it could just have a bad accelerator pump diaphragm. I did notice the data plate on the dash is not the original and is riveted to the dash where the originals were attached with screws. Where did you find the XCL's?
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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