1947 Farmall B Tractor---problem!!!

[kakky]

My B tractor is skipping very badly and the spark plugs have excessive black build-up after I run the tractor each time. I had compression checked---it's ok.----new wiring installed----new distrubtor cap and rotor---has electronic points.
Had carburator checked---checked o.k. Valves were adjusted and checked the exhaust manifold for leaks--sems o.k.
It still skips--don't know what else to do---anyone with any ideas? Thanks for any info

 

[Dave from Texas]

Sounds like it is running way to rich. Is there a restriction in the air flow? Choke, plugged air filter, to much oil in the filter bath, hole in the manifold between exhaust and inlet are some possible problems.

 

[Revredneck]

Black deposits on the plugs is either oil (wet) or too much fuel (dry and fluffy). I would take another look at the carb. It may be adjusted too rich, or the float may be misadjusted or loaded and dropping. Are you sure the choke is staying all the way open? You might also check to be sure your plugs are the proper heat range. If they are too cold, they will get those black deposits on them, too. HTH
Good Luck and God Bless

 

[kakky]

I also meant to mention that when I screw "the screw" all the way in, the tractor will not shut down. You can screw it all the way in and all the way out and nothing happens. I have been told this screww adjustment "should" shut the engine down, but it does not.
Excuse my stupidity--- I am the wife trying to help---

 

[Dave from Texas]

Rebuild the carb and check the float level.

 

[kakky]

Dave---wife here again---we have had 3 tractor/mechanics to look the carb over--it has been cleaned and buildup removed---all 3 said carb is "fine". They find no problem with it.
Also, if and when this problem gets resolved will that adjustment screw work as it is suppose to i.e. shut engine down.

 

[rustyfarmall]

(quoted from post at 06:23:17 08/19/09) Dave---wife here again---we have had 3 tractor/mechanics to look the carb over--it has been cleaned and buildup removed---all 3 said carb is "fine". They find no problem with it.
Also, if and when this problem gets resolved will that adjustment screw work as it is suppose to i.e. shut engine down.

I don't know who your 3 tractor mechanics are, but I can tell you that your carburetor is NOT fine. Anytime an adjustment screw can be turned all the way in or out without effecting how the tractor runs indicates a dirty carburetor. The carburetor needs to be completely disassembled, immersed in carburetor cleaner overnight, blown dry, inspected, and if all passages and orifices are now clean and open, reassemble with new gaskets and hardware.

 

[Bkpigs]

Just a shot in the dark but have you checked the timing? The timing may be off causing it to miss which in turn would cause the plugs to get sooted up when all the fuel doesn't get burned.

 

[kakky]

How do you check the choke to make sure it is open or closed completely?

 

[rustyfarmall]

Remove the rubber hose that connects the carburetor to the air cleaner and look at the choke.

 

[kakky]

Timing has not been checked.

 

[kakky]

Husband agrees with this carb problem too....he wants to have it soaked overnight and all new parts put in it---he is still going to check the choke and airbreather and hopefully get the timing checked. Thanks for all of this info.

 

[gene bender]

Put four new plugs d-21 or their equal. What are you doing with the tractor using or just driving around as they are made to use. Do you have a mag or a dist and are you still on 6v pos groundas over the yrs many changes were made and soon things get all screwed up. I have 8 of them but they do get used. Does the carb have the adjustable jet on the front at the bottom towards the generator.

 

[kakky]

Have put in new d-23"s (4). I Use the tractor for bushhogging and just general use i.e. logsplitter being pulled etc. I have distributor now instead of the magneta. Had this changed out about 2 years ago.

I have 12v neg. ground. Tractor has no generator. Battery has to be charged occassionally.
I have a Carter Carb on it. The only adjustment screw I see is on the top front part of the carb, pointing outward.

 

[Dick L]

You might want to check the battery out put voltage while it is running. I have 4 tractors that I only use occasionally that do not charge the battery while running. Every now and then a battery will break down and cause the engine to run rough. I use a jump start battery to start them rather than keep them charged up. A new battery fixes that problem. Not that it is your problem but one I have had.

 

[ScottyHOMeY]

Now there's a clue. I'd suggest an alternator to keep that battery charged as a good first step. I know next to nothing about electronic ignitions, but you've got a tractor that will turn a starter just fine on 10 volts, so it may seem your battery is healthy, but from that point on down your spark is a lot less reliable. With your governor bailin' the fuel to it bush hoggin', it ain't gonna take too many missed sparks due to low voltage to foul any plug.

The others are talking sense about the carb, too. At idle, that adjustment screw mounted on the throat of the carburetor should be able to bog the engine right down, If it doesn't, the carb needs work.

And a D23 seems like an awful hot plug to be brush-hoggin' with.

 

[Anonymous-0]

Still running the 6 volt coil?Is there a resistor in the primary?Check the voltage on the coils primary.

 

[gene bender]

O.K. Your plugs should burn clean as you do have a load on the engine and not just messing around. The Carter doesent have a load adjustment. Now your carb mite be for a larger engine therefore its getting too much fuel.Do you know where the carb came from as it can be jetted too much for that engine. It sounds like you have checked the other stuff. Have you used a timing lite as you mite need a little more advance and its also possible that the advance on the dist is not working either. The timing mark on the flywheel is hard to find so if you can find it mark it with chalk so it would show with the timing lite. at full throrrle you should have around30 deg advance if the dist is working correct. You can see with the timing lite when it is running o if you could find someone who has a strob machine to check out the dist.That and the carb would be the two things to check. as always glad to help. mite want to call me 319-430-3907 later gene

 

[kakky]

I will try this also---thanks so much

 

[ericlb]

rustyfarmall is right anytime you can completly close the adjustment screw and the tractor will stay running you got a carb problem, also if you open it too much at idle the tractor should run very rough or flood out and die, you need to have a real mechanic check the carb out, it may need a complete kit but first they need to determine just how the engine is getting fuel enough to run with the adjustment screw closed off, this means that when the screw is properly set the tractor is getting much more fuel than it needs which is what causes your fouled plugs

 

[Leroy]

A lot of mecanicks do not know anything about carbs. I had a Ford tractor that was not running right and would completely stop on me. Took it to the local Ford tractor dealer, I knew it was the carb, said nothing was wrong, I could see without taking it off the tractor the seal around the throttle shaft was gone. Took it off byself and took carb to a person that used to be a Ford tractor dealer-mecanick quite a bit further from home, confirmed that the seal was missing and it had an accelerator pump in it like a car (yours does not have this) and it was frose-stuck so bad he could not get it out and had to sent to a speciality shop to get it apart so it could be rebuilt. So probably your carb people are like my Ford tractor dealer shop and that they do not know how to work on a carb, deisel they new but not gas.