# Need help with 1955 Model 50



## John1951 (Jul 17, 2018)

Good morning Gents,

Working on a 1955 Model 50 for a neighbor, no one else wanted to touch it. just as a point of info, I had a motorcycle shop, work on my own cars, etc. so am familiar with motors and carbs. Can't seem to keep this running. Good compression, rewired, static timing fine, new battery, carb cleaned (DLTX-86 model), has spark and new plugs. I think carb is screwy. I can spray gas into inlet and she will run. Stops when I don't spray. I've been over the carb numerous times (2+2, air compressor spray, new gaskets, new o ring on metering valve) taken completely apart. Cleaned ports and channels with guitar strings (old carb trick). Seems it will not suck gas, but when the carb was off and I hit the starter it nearly sucked my hand into the manifold, so we're good there. Maybe I'm missing something! Help!


----------



## RC Wells (Dec 26, 2008)

If you cannot get gasoline draining out of the carburetor intake when you attempt to "choke" it excessively check the following: 
Tank outlet plugged.
Fuel filter in the glass bowl plugged.
Fuel shutoff valve, be sure it is open and fuel is flowing.
Carburetor float not opening the needle valve.
Needle valve stuck or plugged.
Pilot jet bottomed out, lightly seat it and then back it out 1 3/4 turns.

If the problem is not resolved through one of the above, these Marvel-Schebler DLTX carburetors on the John Deeres will corrode and pit internally from the use of modern pump fuel with ethanol or methanol alcohol in the mix if not drained after each use. The old pot metal is highly susceptible to corrosion from moisture in the air combining with the alcohol. Sometimes they will perforate internally and not allow fuel through the primary idle circuit. However, if you choke the dickens out of it, it will still drool fuel out the intake if fuel is getting to the carburetor.


----------



## John1951 (Jul 17, 2018)

RC Wells said:


> If you cannot get gasoline draining out of the carburetor intake when you attempt to "choke" it excessively check the following:
> Tank outlet plugged.
> Fuel filter in the glass bowl plugged.
> Fuel shutoff valve, be sure it is open and fuel is flowing.
> ...


Plenty of gas flow into carb from tank. Fresh gas. Float was adjusted and checked with bowl off re gas flow. 
Needle valve cleaned with mineral spirits. I had the metering valve backed out about 2.5 turns. I will tell you that in the old days when i had my mc shop, i would strip dirty varnish filled carbs of all parts and boil them in vinegar and water. Crap floated to top like you were making chicken or ribs. Dried them out and did the gumout thing. Worked wonders. This trick may be my last resort. Owner not going to spend 400 or more for a new one i am sure
Thanks for the reply RC, much appreciated.


----------



## RC Wells (Dec 26, 2008)

The needle valve is likely one of the later Viton tipped versions. Check to be sure it is not sticking once the bowl fills. Easy to do, just pop the drain plug and if fuel keeps coming you have eliminated that item.

I use very fine acupuncture needles to clean the jet passages once one of these has been disassembled and cleaned with a chemical. Unfortunately the old vinegar and water trick does not work well with the gum/varnish formed by the new pump gasolines. I use Honda carburetor cleaner in a spray can. No foam, and formulated to dissolve everything. Just do not get it in your eyes or on your skin, pretty wicked stuff, right up there with sheep dip of old. Blast the ports, once the jets have been removed, let it soak about half an hour, and blast it again. Use your wire to clear any chunks, and then give it one more blast. Should be ready to go if the jets are clear. 

The paint will come off when you clean the carb with the Honda cleaner.

The design of this carbs allow old hardened varnish debris to drop right into the idle and main jets and clog them immediately.


----------



## John1951 (Jul 17, 2018)

RC Wells said:


> The needle valve is likely one of the later Viton tipped versions. Check to be sure it is not sticking once the bowl fills. Easy to do, just pop the drain plug and if fuel keeps coming you have eliminated that item.
> 
> I use very fine acupuncture needles to clean the jet passages once one of these has been disassembled and cleaned with a chemical. Unfortunately the old vinegar and water trick does not work well with the gum/varnish formed by the new pump gasolines. I use Honda carburetor cleaner in a spray can. No foam, and formulated to dissolve everything. Just do not get it in your eyes or on your skin, pretty wicked stuff, right up there with sheep dip of old. Blast the ports, once the jets have been removed, let it soak about half an hour, and blast it again. Use your wire to clear any chunks, and then give it one more blast. Should be ready to go if the jets are clear.
> 
> ...


RC,
Yes, Viton tip on the needle valve. I will see if any of the auto places have the Honda stuff and give that a try. Not worried about the paint coming off, we can deal with that later on. Thanks again, I will let you know how this turns out.

John


----------



## RC Wells (Dec 26, 2008)

I buy it at the Honda motorcycle dealership.


----------



## John1951 (Jul 17, 2018)

RC Wells said:


> I buy it at the Honda motorcycle dealership.


Yes, found a dealer not 4 miles from here and they have it.
Thanks


----------



## John1951 (Jul 17, 2018)

RC Wells said:


> I buy it at the Honda motorcycle dealership.


Picked up the carb cleaner, took everything apart and cleaned as best as I could. Will be putting back on in a few days, and hoping the bowl gaskets don't leak (another weird design)


----------

