Need help Carter YS 950

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tankjeepman
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Need help Carter YS 950

Post by tankjeepman » Sat Nov 11, 2017 8:04 pm

I am working on a M38A1 with the Carter YS 950 carb. When we went to adjust the idle screw, we noticed the housing that the screw was turning in was loose and leaking fuel. It turns out that someone had taken the idle screw, threaded a 10-24 nut on it, wrapped a piece of plastic around it and pushed it into the throttle body housing. The oblong cover is missing. We found a diagram that shows a what looks like a black donut seal? that appears to go into the housing. We can see what looks like this part in the carb rebuilt kits.

So the question is what does the idle adj screw thread into? If it is this seal then the cover has a small piece that is pressed into the small hole above the hole that the screw goes in? It doesn't seem this would be very secure. Any help and detailed pics would be appreciated.
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Scoutpilot
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Re: Need help Carter YS 950

Post by Scoutpilot » Sun Nov 12, 2017 7:01 am

Your description reads like this is the Idle Mixture Screw. The housing is the Throttle Flange. This is an assembly consisting of the knurled/slotted-head screw itself, a tension spring the screw fits through, a thin metal plate and the rubber bushing which fits in the recess just outboard of the threaded portion of the passage. As the screw is turned in, or out, tension from the spring against the plate, which presses against the bushing, keeping it tight, is either increased or decreased. If fuel is leaking from this port, the carburetor is probably flooding.
'70-'71 'A' Batt., 377th FA, 101AB
(Slicks and LOH's)(Col's LOH Pilot)
'71-72 CHARLIE TROOP,
16TH AIR CAV, 1ST AVN BDE (AEROSCOUTS)
LOW LEVEL HELL.
'46 CJ2A
'47 CJ2A
'48 CJ2A
'48 B1PW126
'69 CJ5

tankjeepman
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Re: Need help Carter YS 950

Post by tankjeepman » Sun Nov 12, 2017 8:52 pm

Thanks this helps. You are right I meant Idle mixture screw. I guess it works, but it looks like the plate being held in place in just one place wouldn't get the job done for very long.
45 Chevy G7107 SOLD
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48 CJ 2A Parts or maybe restore?
M151A2 1973 In Progress
M151A1/A2 Conversion to A2

tankjeepman
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Re: Still Need help Carter YS 950

Post by tankjeepman » Thu Dec 07, 2017 8:33 am

We got the carb rebuild kit and assembled the new seal, needle & spring and plate. The seal slides too easily in the hole and will not stay in. Even when we turn the screw compressing the donut seal, it does not stay in the housing. We put a little silicone it and ran awhile before the idle mixture screw assembly fell out. We have secured it with a tie, but there has to be something we are missing. The housing appears to be in good shape and I don't see how the hole could be the problem. Maybe the seal is too small?
45 Chevy G7107 SOLD
45 MB In Progress
48 CJ 2A Parts or maybe restore?
M151A2 1973 In Progress
M151A1/A2 Conversion to A2

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Re: Need help Carter YS 950

Post by Scoutpilot » Thu Dec 07, 2017 9:30 am

I have never had that happen. In the kit should be three different size rubber bushings. One is for the Choke Shaft. One is for the Idle Mixture screw. And one is for the Throttle Shaft. There are only two reasons for the Idle Mixture screw to fall out. The idle mix orifice is stripped or the screw is too small. Pictures would help.
'70-'71 'A' Batt., 377th FA, 101AB
(Slicks and LOH's)(Col's LOH Pilot)
'71-72 CHARLIE TROOP,
16TH AIR CAV, 1ST AVN BDE (AEROSCOUTS)
LOW LEVEL HELL.
'46 CJ2A
'47 CJ2A
'48 CJ2A
'48 B1PW126
'69 CJ5


tankjeepman
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Posts: 226
Joined: Fri Apr 20, 2007 4:26 am
Location: Lucas, TX

Re: Need help Carter YS 950

Post by tankjeepman » Thu Dec 07, 2017 2:30 pm

I will have to check next week, but I don't remember seeing more than one rubber seal. I volunteer at the Cavanaugh Flight Museum and it's their Jeep. Is the needle suppose to screw into the housing or just the rubber seal? The housing was cleaned and it didn't look there were any threads ever there. There was a new needle with the kit, it is the same size as the old one.

I just reread your first post. I did not catch the first time when you said 'the threaded portion of the passage'. So I guess that answers my question. If the throttle base is suppose to have threads then ours is bad.
45 Chevy G7107 SOLD
45 MB In Progress
48 CJ 2A Parts or maybe restore?
M151A2 1973 In Progress
M151A1/A2 Conversion to A2

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Scoutpilot
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Re: Need help Carter YS 950

Post by Scoutpilot » Thu Dec 07, 2017 3:18 pm

If you find that is the case, convince them to send it to me and I’ll fix it for free. Call it a donation from a former Army Aviator.
'70-'71 'A' Batt., 377th FA, 101AB
(Slicks and LOH's)(Col's LOH Pilot)
'71-72 CHARLIE TROOP,
16TH AIR CAV, 1ST AVN BDE (AEROSCOUTS)
LOW LEVEL HELL.
'46 CJ2A
'47 CJ2A
'48 CJ2A
'48 B1PW126
'69 CJ5

tankjeepman
G-Command Sergeant Major
G-Command Sergeant Major
Posts: 226
Joined: Fri Apr 20, 2007 4:26 am
Location: Lucas, TX

Re: Need help Carter YS 950

Post by tankjeepman » Thu Dec 14, 2017 8:36 pm

Our throttle base does not have any threads for the idle mixture screw. I have talked to our lead and your offer is something we will take advantage of. How will you make threads in the cast iron base? Press the correct diameter brass tube into the hole and tap the threads for the screw?
45 Chevy G7107 SOLD
45 MB In Progress
48 CJ 2A Parts or maybe restore?
M151A2 1973 In Progress
M151A1/A2 Conversion to A2

User avatar
Scoutpilot
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Re: Need help Carter YS 950

Post by Scoutpilot » Fri Dec 15, 2017 3:25 am

No sir. I’ll simply replace the entire throttle. Give me an email address so I may send the request for service form to you.
'70-'71 'A' Batt., 377th FA, 101AB
(Slicks and LOH's)(Col's LOH Pilot)
'71-72 CHARLIE TROOP,
16TH AIR CAV, 1ST AVN BDE (AEROSCOUTS)
LOW LEVEL HELL.
'46 CJ2A
'47 CJ2A
'48 CJ2A
'48 B1PW126
'69 CJ5

tankjeepman
G-Command Sergeant Major
G-Command Sergeant Major
Posts: 226
Joined: Fri Apr 20, 2007 4:26 am
Location: Lucas, TX

Re: Need help Carter YS 950

Post by tankjeepman » Fri Dec 15, 2017 8:12 am

45 Chevy G7107 SOLD
45 MB In Progress
48 CJ 2A Parts or maybe restore?
M151A2 1973 In Progress
M151A1/A2 Conversion to A2

User avatar
Scoutpilot
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G-Lieutenant General
Posts: 6086
Joined: Sun May 28, 2006 2:22 pm
Location: Asheboro, NC

Re: Need help Carter YS 950

Post by Scoutpilot » Fri Dec 15, 2017 10:09 am

Check your eMail. May be in the Junk Mail.
'70-'71 'A' Batt., 377th FA, 101AB
(Slicks and LOH's)(Col's LOH Pilot)
'71-72 CHARLIE TROOP,
16TH AIR CAV, 1ST AVN BDE (AEROSCOUTS)
LOW LEVEL HELL.
'46 CJ2A
'47 CJ2A
'48 CJ2A
'48 B1PW126
'69 CJ5

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