Oil & Fuel 1949 8N: Fuel not going through carb

[cfb]

Hello All,
I was happy to get spark in all four plugs. Then went to the fuel. No fuel was going from the sediment bowl assembly into the fuel line. I took it out and drained the old gas. I guess it had that dreaded kerosene small I read others having. I took the bowl and filter off and the entry hole was plugged solid. The top filter that goes into the tank may have been home made as it was soldered shut at the top so I could not see inside as I suspected that entry area was plugged to. So, since I could not get to it, I decided to buy a new fuel assembly. And I decided to buy a new fuel line too as the old one was modified to install a small in-line filter which I read is a no-no.

Although it was not the web site company I bought from, the parts came from Atlantic Quality Parts. The bowl assembly was part 1103-3397 which replaced 2N9155B. The fuel line was part 1103-3430 which replaced 9N9282A. The top filter that goes into the tank was about an inch or so and open at the top with a center"pipe". It did not look perforated as I was expecting but maybe it is just very tiny for me to detect. Anyway, it screwed into the tank. I used a little of the yellow tape I read was recommended. It did not seem to screw in as far as the one I took out, but lined up okay and did not leak.

I connected the fuel line next. I tried my best, but just did not seem to get it lined up correctly at the assembly. The end fitting just did not seem to want to screw in easily. Well, I ended up stripping the inside of the assembly, so I'll be buying a new one of those, but leave that aside for now for this discussion. It screwed in very easy at the carb into that elbow piece. So then I added gas - this was before I stripped the inside thread in the assy and it was leaking. The valve stem of the assy did not seem to work right. It was hard to turn and when I had it all screwed in tight it did not stop the flow as I thought it should have. That is when I started to play around and ruin the inside threads. The threads of the pipe fitting seem fine as it must be harder metal - perhaps that is my design.

1. When I added gas to see the bowl fill up, I did not have to add much gas before it started to fill, less for sure than the reserve gallon, which sort of confirmed that the assy did not screw in very far, but I could maybe go a quarter turn more but then it would not be aligned. So I added gas to get the pressure up to push through the pipe. So I disconnected the pipe at the carb to see nice flowing gas there. But the end at the assy was leaking.

2. The fuel pipe, by the way, goes up slightly after the assembly before going across the engine and down into the carb - is that up slope correct?

3. I mentioned above that the valve stem did not stop the flow. Should it have and I really had a faulty unit? I tried to pull the step out like I did on the old assy but it would not screw out after I loosened the plug. That seemed odd too - would you all agree?

4. Then I took out the plug at the bottom of the carb ( after I reconnected the fuel line at the elbow) - no flow. I turned the engine on to pulled the choke thinking that would file the carb - not sure if that exercise would or not, but still no flow out the bottom. I did earlier that out that elbow and that inside filter was very clean.

I'd appreciate you comments above both on that valve assy and that stem not stopping the flow, and if there is a trick to getting the pipe fitting to thread properly into the assembly unit. Does not flow out the bottom of the carb mean the carb is clogged? is this something I can clean out myself or should I be looking at replacing it?

You should no too that it was running in the past, but I probably left the gas sit much too long as I did not have oil pressure and did not have time to address that until now.

thank you for your responses/help in advance. cfb

 

[jaxs]

Considering how bad the valve,filter and line were clogged,it's almost certain the carb is in the same shape. Those are simple carbs with few parts so I suggest A. Looking for a metal tag attached to carb B. Copy #s off tag to order a rebuild kit. Cleaners available to consumers are not very aggressive so inquire around your area to see how much a professional will charge to"boil out"your casting. If you must wing it,have compressed air,small brass brushes and various size copper wire to push through small passages available when you clean it.

 

[Soundguy]

The knob should have shut fuel off, yours was defective.

You might still be able to fix your old one. That screw over the pickup tube will come off.

As for the carb. Might be a plugged up elbow screen, might be a plugged up float valve, or stuck float.

Is it a MS or a zenith carb? If it is a Ms tax 33 or a 241a/b/c variant, the same kit rebuilds all 4. Basic kit has gasket, and small parts, larger kits have venturi, floats, and butterfly parts . Usually you can get by with basic, unless your floats bad or choke or throttle butterfly are bad.

Post back before you get that far.

Remove elbow and get a can of carb cleaner. Look at carb, there is a small hole behind elbow for fuel to flow. With bottom drain open, use the straw in your carb cleaner and blow son shots the it. Shield your eyes in case you don't line up the straw to the hole good and you get spray back.

If still no flow, carbs coming apart.

Ms carbs are easy. Pull main needle, remove 4 Dec screws, separate, keep venturi facing correct, you might have to peel gasket to get floats out .. From there, manipulate float and watch needle, blow cleaner thru.

Might as well blow out bowl, main, and 2 small ports. Regasket getting float and venturi in correctly, assemble dry, saves the gasket, in case you have it apart again.

Post back.

 

[cfb]

Thanks for the comments:
1. regarding the valve stem, Soundguy, what do you mean by the pick up tube? I did unscrew the nut over the stem but the valve stem never screwed out like the one I removed.
1b. Also, on my old one, the one I took out, I tried, just to see if it would work, I threaded my new fuel line into the old assembly. It threaded nicely but stopped before the pipe was seated as I could still move it slightly. So I did not screw it in any further as I did not want to strip the old part. I got the same pipe part number as in my manual.

2. Carb: It is a Marvel Schebler. It is stamped in the front and back of the carb. I think I see a worn 33 also stamped into the front of the carb on sort of a tear drop shape on the carb. There is a stamped #5 near the company name and what looks like the letter B stamped near the top of the carb.
2a. On the underside, next to the plug, there is a round piece that looks part of the casting with four small slots on the edges, but in the center of it, looks like a filter, about 1/4" round. What is that? My parts manual does show a plug and strainer. Is this something from the inside ? what is its purpose?

2b. The elbow screen seems very clean to me.
2c. I did not see any metal tag attached to this carb, nor even a place where it might have been? So do I probably have an older unit?

2d. So I guess now I'm facing removing the carb to work on it. How do I disconnect the choke and throttle rods from the carb unit? They seem to be on a ball swivel, but on the backside, was hard to see a set screw or something. As a side bar, when looking at the choke rod, it seems to be rubbing on the oil pipe from the filter. I don't think I should be bending it, but can I put a protective plastic hose around it to stop the rubbing or some other solution?
2e. I'm going to get that carb cleaner now and blow some shots of it into that elbow and see if anything comes out of the bottom plug.

 

[Soundguy]

if it's a small ms carb.. that's all you need to know. the gasket is the same..

Pickup tube is the port in the tank the gas flows thru.

the choke n throttle have captive ball joint ends, and the carb throttle and choke have balls. the ends are spring loaded. pull the end away from the rod and the ball pops out.

bend the rod that rubs.. bending is fine. in fact.. it's how you adjust the governor..

 

[jaxs]

the choke n throttle have captive ball joint ends, and the carb throttle and choke have balls. the ends are spring loaded. pull the end away from the rod and the ball pops out.
..

That is correct but this additional disassembly instructions will make it easier for old rusted joints. Spray joint with a shot of WD 40 or penetrating oil. Hold rod in one hand then with other hand,pull end away from rod and ball will pop out.
Too late to worry about the tag,it wasn't reattached during an earlier re-assembly. The tag was held by any one of the bowl screws so it fall's off when that screw is removed. Knowing that might help later on another carb one day.

 

[cfb]

Hi, thanks again for comments and clarifications.
well I tried to flush up the hole in the elbow and nothing came out the bottom. So now I'll start the removal process.

a. how likely is it that I would need to replace the choke and throttle butterflys? The kits I saw include a lot including the rods for $27 which seems pretty good from what i saw on other sites, but if I need the butterflys, I go to a premium kit for about $60. Do you or anyone know of a kit number and vendor you like? Am I basically looking for a kit for the Marvel and mfg TSX33? My manual says repair kit APN9590A, but don't know what it would include.

thanks.

by the way, the on-line vendor I bought the sediment bowl assy is sending me a replacement - which I was very pleased to hear.

 

[jaxs]

The butterflys probably be ok but you might wait until you disassemble to check them out. Another reason to wait before ordering the kit is if casting is damaged,you'll need a replacement carb. The shaft bushings come in the basic kit and sometimes need to be replaced. The most critical part is float,needle & seat. Get those right and the rest is pretty forgiving.

 

[cfb]

Okay, good idea to wait. thank you.

 

[cfb]

Well, got the carb off. The rods came of fairly easy once I realized what I was told above and how it works. Spring end seems pretty good. I did squirt them with penetrating oil.
a. the gasket stayed on the engine. Should I just remove it - I think a new one comes in a kit.
b. I'm going to take my time as never done this before. Taking pictures and notes alone the way.
c. I want to screw in first the two set screws just to see how far they were then screwed out.
d. The choke butterfly looks good, nice and clean, at least from what I can see before disassembly. The spring mechanism where the choke rod is attached, is a firm spring action. When relaxed, the butterfly is horizontal or open. When I pull the spring, it closes. If this seems to be functioning properly, should I just leave it alone?
e. The top, throttle butterfly also looks nice. but maybe what do I know. I'm pretty sure now that the guy I bought it from had worked on the carburetor. Anyway, the mechanism where the rod connects, is not a spring action setting like the choke is. I this area basically closed or near closed (horizontal) when at low idle and as you increase throttle, the butterfly goes toward vertical?
e1. when I push it so the butterfly is vertical, it is not exactly perfectly vertical, nor the other way, is it perfectly horizontal. Is this okay?

thank you.

 

[jaxs]

A Since it stayed on the intake manifold and will not interfere with rebuilding carb,leave the gasket until you see if a new one is in the kit you ordered.
B. Good plan
C. That's called experience
D. If shaft is tight,don't dis-assemble butterfly assembly.
E.You are correct about position(s) of butterfly
E1. Both are normal and we can talk about why after you comprehend the bacics.
Be gentle but thorough in cleaning passages. Remember,copper,wood and plastic will not scratch iron plus quility cleaner and compressed air is your friend. You need to get every speck of crap out but don't want to scratch or enlarge a passage. Very difficult to comprehend why this is so important but take my word and we can discuss it later if you are still wondering.

 

[cfb]

Hello Everyone,
I received my replacement sediment b owl today. I tried, off the tractor, to screw in the fuel line. I think I see the problem and wonder if I'm doing something wrong or need to order from another vendor.

When I screwed in the fuel line to the previous sediment bowl assembly, I strip the assy threads - a softer metal than the fuel line nut. I thought I started threading it correctly but then it stopped and I still did not have the line seated, so I continued to screw in the nut.

With the new assembly, I screwed in the fuel line nut , again until it stopped, and the fuel line was still loose. So I looked inside the assembly threads and see that it is only threaded half way. This was the case also I see now with the previous assembly. I then looked at the old clogged assembly that I'm replacing, and it had threads all the way, or practically all the way down to where the fuel line seats.

Could I possibly have a mismatched assembly and line? I got the part numbers right out of my manual. I got these from an on-line vendor, but the parts came from a distribution center called Atlantic Quality Parts. When I view assemblies,same part number, on other on-line vendors, the assy looks the same. The same image on any site I view.

Maybe someone can share the part numbers they've had success with and vendor, too please. This is a 1949 8N.

thanks - trying to stay patient.

 

[cfb]

well, I finished tearing down the carb. Boy, some screws tested my strength. It is really fascinating how this is put together, all the little holes. I think I got all the holes and have clear flowing now. I'll do a more thorough job again. All those brass screws/needles I removed look fine. Can they be pitted slightly unseen by the eye and that is why I should replace them? The venturi is plastic. The float looks to be in good shape, brass. But there was no spring at the base where the little connecting rod is. Do some designs call for it and some not? The idle screw was backed off just a tad over one full turn which is what I heard it should be. The main jet screw, however, was also just a tad beyond one full turn - I heard this one should be closer to two. Or could it have that far of a range or gets adjusted if the carb is not fully clean like I hope to have it? The throttle butterfly is a thick brass piece, but it has some nicks on its edges. Is that significant if not absolutely smooth? thanks again.

 

[Soundguy]

small nicks on the throttle butterfly won't be an issue.

The plastic venturi is not desireable, but works.

the half threaded fuel bowl is not correct.

 

[cfb]

Hello everyone,
Hurray, it starts! Well, sort of.
So, my replacement bowl assembly kit had the same problem, the port for the fuel line was only half threaded. So I got one from my Ford dealer and it worked fine. But I had to get the top end totally screwed in before I screwed in the other end into the carb. I also got a basic carb kit from Ford too. That was fun. I'm still amazed at this construction. I thought I may have put the throttle rod in backward, if that is possible, but i looked at my pictures and i think I got it right.
a. I put gasket seal and the yellow, fuel resistant teflon, on the carb drain plug and it still won't stop leaking? What do I do next?
b. It took a while, flooded a few times, but eventually started. But still I don't think it should take me numerous times to start. I do have vacuum by the choke port of the carb. Is it the compression of the pistons that pulls fuel to the spark plugs? I don't have a tester, but it does suck on my finger and also has a good explosion out too. Could my spark be insufficient?
c. I put the main jet and idle mixture jet both out one turns, which is where they were when I took the carb apart and what by manual calls for.
d. But it seems I had the throttle lever by the steering column all the way up more than what I recall before when I was getting ready to drive it.
e. Related, after it warmed up a bit, I put it into first and the engine died. It did this a few times and then I could drive it about 30 feet out of the garage, but then it died as I turned and went up a gentle upslope. Each time thereafter, it died as I was releasing the clutch. Tomorrow I'm going to add a few more gallons of gas to see if that could be the reason. The new fuel assembly did not screw in very far, I could have gone a 1/4 turn more, but then would have been out of position to received the fuel line. I don't recall if I just got one turn in or two. Just on the side, are there flexible steel fuel lines? So, my fuel bowl filled up after only putting in a 1/2 gallon of gas. I later added another half gallon, but wondering if the incline was enough to push the gas toward the steering column and not allowing sufficient gas down to the carb when I put in into gear ( no more gas was leaking out the drain plug).

I appreciate your continued help. thanks, cfb

 

[jaxs]

:confused3: I don't know were to begin.

 

[Soundguy]

atmospheric pressure is what pushes air in on a naturally aspirated engine, and you don't have a turbo or supercharger.

1 turn out on main needle.. I'm surprised it starts, unless the jet is incorrectly oversized, or the needle is undersized where it seats.. I'd bet it would be happier somewhere around 2 turns out.

1/2 gallon of gas in a 10 gallon tank means you are essentially, out of gas.

leaking out of the pipe plug bottom port on the carb means you probably have too much bubble gum n snot on the plug. remove the plug, clean the male and female threads.. check fit dry, then try it just with a liquid/paste type sealer. if it still weeps, and the plug is cast iron, replace it with a brass plug, add the paste, then tighten it and re-check. Remember.. NPT threads seal by thread deformation. if it's loose, it can't seal. some threads get cut a little odd, and you experience a little resistance screwing it in, but before it is sealed, so sometimes giving it a little extra twist helps. the brass plug helps because it is soft and deforms easier.

if you had rods in backwards.. your linkage hookup would be apparent and wrong.

she's stalling on load because she is probably very, very lean.

Still, it never hurts to check spark.. it's free, and easy.

And you can check spark at stall.. if it has spark after stall.. it's fuel.

 

[cfb]

Thanks Soundguy,
that's what I figured as I was thinking (and praying) about it last night. Prayer was answered. Last night at our tractor club Christmas dinner, a guy said to open the main jet some more which is what you said too. I added a few more gallons of gas this morning and opened up the jet 1/4 turn. [ I'll recheck my manual, but pretty sure it said just one turn, but I watched a video put out by Steiner who said just what you said - two turns. ] Also, I'm the guy too that lost the oil pressure, which was my whole goal when I started this venture. I did try the "prime-the-pump" routine through the front engine pressure relief plug yesterday, but no oil pressure. The same guy from last night told me to just load up the hole with oil. So I did that too this morning. The tractor started right away. AND, oil pressure came back pretty quickly too, just under 40 psi at almost full throttle. I put the tractor in gear, released the clutch and hurrah, off I went. Talk about happy! This was my Christmas present. I, of course, just had to drive around the yard several times. I died off an on in idle. I add more gas. Oil pressure came back each time. I backed it into the barn and after an hour or so maybe, started it up again and got pressure. So will try again tomorrow.
Surprisingly, the bottom carb plug was not leaking anymore, so obviously very pleased about that. The plug I have is brass, so interesting about the different types. Out of curiosity though, can you give me a name of the paste I could use that you referenced? I should say too, that the tractor starts right up now on just a minimum choke. And it idles nicely down too so I an go slowly with pressure around 30 psi, maybe a little less. Some more work to do now on other part, but I have my garage back now.

 

[Soundguy]

paste like harveys, oatey or gasoila.

1.25 turns is still probably a hair lean, depending on what the needle and jet looks like. I'd try 1.5 turns and set there and gas it looking at the exhaust. As a rule of thumb, you can increase the main jet a little and check by throttling it up and down and looking for a puff of black sooty smoke.. once you hit the sooty smoke, you back it down till the sooty smoke stops. then you know you aren't lean. Lean mixes can cause or worsen heating issues. Sometimes at night or in the dark, you will notice your manifold glowing red if you are too lean. Lean also can make for popcorn farting and dieing at low rpm when a load is applied.

 

[cfb]

Thank you for this added explanation. Quite helpful actually for my understanding. Definitely do not want a glowing manifold. I will try this later today.

Would you mind sharing what that gasket paste is that you speak of? name/brand. thank you,