Zeph's '42 Ford GPW

Create a thread to track the progress of you MB/GPW restoration progress. Previously a General Discussion board.
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Mark Jesic
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Re: Zeph's '42 Ford GPW

Post by Mark Jesic » Sun Jul 09, 2017 8:46 am

Ah, thanks for that Zeph, we dont have 409 over here, as for the Beach Boys, now your talking ! :D


chibobber
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Re: Zeph's '42 Ford GPW

Post by chibobber » Sun Jul 09, 2017 11:19 am

The Chevy 348/409 was a great high torque motor.That being said,If you tried to rev them like a small block,you would blow the cranks out the bottom. :o

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Re: Zeph's '42 Ford GPW

Post by sawbuck » Wed Jul 12, 2017 6:58 pm

chibobber wrote:The Chevy 348/409 was a great high torque motor.That being said,If you tried to rev them like a small block,you would blow the cranks out the bottom. :o
The 348 was originally designed for Chevrolet trucks so high torque, low rpm. 409 was an attempt to adapt for high performance.

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Re: Zeph's '42 Ford GPW

Post by Chuck Lutz » Thu Jul 13, 2017 6:07 am

Zeph...if you have to drive with the choke pulled OUT then there is a serious air leak somewhere. After seeing the broken manifold, I wonder if you had the intake/exhaust manifolds milled FLAT when you did the overhaul? That may be the place where air is getting in or...the carb/manifold gasket....or, the throttle shaft needs to be bushed. One or more of these issues allow too much air into the system upsetting the 16-to-1 mixture of air the carb is designed and the engine needs....to compensate for a big air leak in those places it is necessary to restrict the air into the carb by pulling out on the choke.
Chuck Lutz

GPW 17963 4/24/42 Chester, PA. USA 20113473 (USA est./Tom W.)
Bantam T3-C 1947

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Re: Zeph's '42 Ford GPW

Post by zepher11 » Fri Jul 14, 2017 9:41 am

Chuck Lutz wrote:
Thu Jul 13, 2017 6:07 am
Zeph...if you have to drive with the choke pulled OUT then there is a serious air leak somewhere. After seeing the broken manifold, I wonder if you had the intake/exhaust manifolds milled FLAT when you did the overhaul? That may be the place where air is getting in or...the carb/manifold gasket....or, the throttle shaft needs to be bushed. One or more of these issues allow too much air into the system upsetting the 16-to-1 mixture of air the carb is designed and the engine needs....to compensate for a big air leak in those places it is necessary to restrict the air into the carb by pulling out on the choke.
Hi Chuck,

Thank you for the information. Yes, I milled the manifold(s) on initial install, and again after the recent repair of the intake manifold. Everything seems to pass my 5/16" fuel line to the ear test now where I cannot detect any hissing indicating a vacuum leak around the manifolds or carb base. That's how I first found the crack in the manifold allowing air in.

This carb is the only unknown on this restoration as I bought it with a few other carbs and just stuck it on and it ran, but I have always had to pull the choke out a bit to run well. This carb was likely sitting in a box for 15-20 years before I stuck it on there. With the choke out a bit, it does run very well.

It possibly may be the throttle shaft as you mentioned. Is there a way to determine if this is an issue while the engine is running? Maybe use the hose to the ear test? I may try that when I'm home tomorrow to see. Or can one just grasp the throttle linkage and feel if there is unacceptable play whatever that may be?

Thanks for the intel!
Zeph

'42 Script GPW Restoration Thread: CLICK HERE!

'41 Dodge WC16 Restoration Thread: CLICK HERE!

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Chuck Lutz
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Re: Zeph's '42 Ford GPW

Post by Chuck Lutz » Fri Jul 14, 2017 11:12 am

I think you may have found the problem is with the wear on the flange on the carb. The throttle shaft itself can also wear but only when you strip it out and mic both the shaft ends and both the flange openings would you be able to tell. The wear is also usually greater on the engine side as that is where the throttle linkage puts the most strain on the shaft/flange locations.

I think if you spray some Brakekleen on the linkage where it enters the flange on the engine side first and then on the fender side while the engine is idling you can tell....if there is a change in the RPMs then you have a leak there. From what I gather, the tolerances are quite small so if you removed the carb and simply wiggled the shaft linkage and found much movement at all, that would indicate some wear has occurred. Since you have a few other carbs laying around I suggest you wiggle a few of them to see if you can detect much movement....that might help you diagnose your carb problem.

If you have a 100% correct 539S and you feel it is running OK otherwise, maybe a bushing job by Scoutpilot is an option. I would contact him to see if that can be done by itself or if you need to rebuild it completely to get the bugs out of it. As an option, if one of the other carbs is a 100% correct 539S then perhaps a restoration of one of them and then you can just do a swap when it returns and not have any down time for the jeep awaiting yours to return.

He does beautiful work; the flanges come back "parked" as well as the Carter factory did, not painted black. If you need help to ID the various components of each of your carbs, email me pics of each one.
1) Patent numbers on Bowl
2) Bowl cover markings
3) Front of Air horn
4) Flange number stamped on gasket surface
5) Air horn and throttle linkage photos (side view)
Chuck Lutz

GPW 17963 4/24/42 Chester, PA. USA 20113473 (USA est./Tom W.)
Bantam T3-C 1947

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Re: Zeph's '42 Ford GPW

Post by cjv-35 » Fri Jul 14, 2017 2:15 pm

Carburetor wise, first I would take the carb apart, remove every jet and clean them. Then check the pump stroke and metering rod adjustment to confirm they are set correctly and if not re-adjust to specs. After doing that if it still runs with choke having to be pulled out then I would be looking at the throttle body shaft for wear as mentioned above.

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Re: Zeph's '42 Ford GPW

Post by zepher11 » Fri Jul 14, 2017 5:32 pm

Chuck Lutz wrote:
Fri Jul 14, 2017 11:12 am
I think you may have found the problem is with the wear on the flange on the carb. The throttle shaft itself can also wear but only when you strip it out and mic both the shaft ends and both the flange openings would you be able to tell. The wear is also usually greater on the engine side as that is where the throttle linkage puts the most strain on the shaft/flange locations.

I think if you spray some Brakekleen on the linkage where it enters the flange on the engine side first and then on the fender side while the engine is idling you can tell....if there is a change in the RPMs then you have a leak there. From what I gather, the tolerances are quite small so if you removed the carb and simply wiggled the shaft linkage and found much movement at all, that would indicate some wear has occurred. Since you have a few other carbs laying around I suggest you wiggle a few of them to see if you can detect much movement....that might help you diagnose your carb problem.

If you have a 100% correct 539S and you feel it is running OK otherwise, maybe a bushing job by Scoutpilot is an option. I would contact him to see if that can be done by itself or if you need to rebuild it completely to get the bugs out of it. As an option, if one of the other carbs is a 100% correct 539S then perhaps a restoration of one of them and then you can just do a swap when it returns and not have any down time for the jeep awaiting yours to return.

He does beautiful work; the flanges come back "parked" as well as the Carter factory did, not painted black. If you need help to ID the various components of each of your carbs, email me pics of each one.
1) Patent numbers on Bowl
2) Bowl cover markings
3) Front of Air horn
4) Flange number stamped on gasket surface
5) Air horn and throttle linkage photos (side view)
I'll see if I can squirt some Brakekleen around the shaft to see what happens. I sold all of the other carbs sometime ago...they went like hot cakes! I'll take some good photos of the carburetor I kept which I believe it is a correct 539S, but not positive. I see the new website here shows the uploaded photos without that annoying scroll function now. Gives me a reason to try it out.
Zeph

'42 Script GPW Restoration Thread: CLICK HERE!

'41 Dodge WC16 Restoration Thread: CLICK HERE!

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zepher11
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Re: Zeph's '42 Ford GPW

Post by zepher11 » Fri Jul 14, 2017 5:36 pm

cjv-35 wrote:
Fri Jul 14, 2017 2:15 pm
Carburetor wise, first I would take the carb apart, remove every jet and clean them. Then check the pump stroke and metering rod adjustment to confirm they are set correctly and if not re-adjust to specs. After doing that if it still runs with choke having to be pulled out then I would be looking at the throttle body shaft for wear as mentioned above.
Sounds good as well. Do you happen to have a link to a thread on here that shows how to adjust the metering rods by chance? I'll search and see if I can find one. I can also pull my manual out, but I really hate to do that unless I absolutely have to do so. :lol:

Thanks!
Zeph

'42 Script GPW Restoration Thread: CLICK HERE!

'41 Dodge WC16 Restoration Thread: CLICK HERE!

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Re: Zeph's '42 Ford GPW

Post by zepher11 » Fri Jul 14, 2017 6:34 pm

Here's some photos of the carburetor in question. Had time to go out and check it out this evening. I did listen for air leaks at the shaft on both the engine and fender side. Maybe a very faint hiss on the fender side. Nothing on the engine side. No change in idle spraying Brakekleen on both sides of the carburetor.

Must say that the photo posting feature here is really a nice set up now:
CC 10.JPG
Carb Photo #1
CC 10.JPG (71.39 KiB) Viewed 9826 times
CC 11.JPG
Carb Photo #2
CC 11.JPG (50.05 KiB) Viewed 9826 times
CC 12.JPG
Carb Photo #3
CC 12.JPG (63.97 KiB) Viewed 9826 times
CC 13.JPG
Carb Photo #4
CC 13.JPG (79.76 KiB) Viewed 9826 times
CC 14.JPG
Carb Photo #5
CC 14.JPG (89.92 KiB) Viewed 9826 times
Zeph

'42 Script GPW Restoration Thread: CLICK HERE!

'41 Dodge WC16 Restoration Thread: CLICK HERE!

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Re: Zeph's '42 Ford GPW

Post by cjv-35 » Fri Jul 14, 2017 8:30 pm

Go to You Tube and punch in Carter W.O. Carburetor Adjustments. Look for pump stroke and metering rod adjustments by Rick Patcholski (Scout Pilot). To adjust the metering rod correctly, you will need the gauge that Ron sells. Remember, check and set pump adjustment Before setting the metering rod. The pump stroke is 17/64 of and inch, + or - 1/64. Rick explains both on his excellent videos.

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Re: Zeph's '42 Ford GPW

Post by cjv-35 » Fri Jul 14, 2017 8:45 pm

Looking at your throttle rod, the connector at the bottom looks to be installed wrong unless you are starting to dismantle the unit.

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Re: Zeph's '42 Ford GPW

Post by zepher11 » Sat Jul 15, 2017 7:21 am

I'll check out the video. Not too sure what you mean about the connector being installed incorrectly. The photos are as installed. I haven't removed anything, but it could be installed incorrectly. I will see if I can find some photos of some carburetor installs.

Thanks!
Zeph

'42 Script GPW Restoration Thread: CLICK HERE!

'41 Dodge WC16 Restoration Thread: CLICK HERE!

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Re: Zeph's '42 Ford GPW

Post by cjv-35 » Sat Jul 15, 2017 10:07 am

In your first pic, it's the silver rod next to the bowl. I'll call it the accelerator pump rod. At the bottom were it goes through the eye on the throttle plate shaft. What is keeping the rod from backing out of the eye ? Could you post a better pic of that area ? Your carb looks to be a post war 636 or 636SA going by the 12 patent numbers bowl and the throttle plate linkage. I have the same type on my daily driver 45 GPW. Not the right one going by the jeep police but hey, at least it's a Carter W.O.

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Re: Zeph's '42 Ford GPW

Post by Chuck Lutz » Sat Jul 15, 2017 11:45 am

Yup...Looks like you have an early 539 bowl cover....but the rest is a 596 - 636 series set of parts. If you need a 100% correct 539S you can assemble one from a couple parts donors you can pick up at the jeep meets or maybe get lucky and find a complete 539S. The other options are buying one or more to come up with a set of 539 components and then either rebuilding it yourself or getting it rebuilt. Be sure to check if it needs to be bushed and/or a new throttle shaft is needed.

The little retainer on the throttle rod that connects to the linkage on the throttle shaft is installed wrong. You should be able to straddle the linkage arm with the retainer and then pass the rod through the retainer and linkage and then push the retainer up and clip it onto the rod to hold it all together.

Check it out in this photo;
Carter 636S Base 505.jpg
Carter 636S Base 505.jpg (60.18 KiB) Viewed 9801 times
Chuck Lutz

GPW 17963 4/24/42 Chester, PA. USA 20113473 (USA est./Tom W.)
Bantam T3-C 1947


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