My 135 starts and stays running with the choke pulled, once I close the choke it stops. I haven't run it for a year, prior to parking, it would stop running once I let the clutch out. This was the reason for parking it and buying a new tractor.. I want to fix it but have no idea where to start.......
MF 135 gas won't stay running off choke
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Kozzy49
New member
I would suspect that you have a vacuum leak. IF this suddenly occurred, check for a cracked vacuum line, or one that has been knocked off. If that checks out, get your self a bottle of water with a spray pump. Start your tractor up with the choke pulled and let it stabilize. Now spray water along the intake manifold, does the RPM change / lug down as if the engine is over fueling? If so it is a good indication you have a leaking intake gasket / loose intake manifold. If there was no change, now spray water around the base of the carburetor, any change? If so check to see if Carburetor is loose. If not spray around throttle shafts, by this time you should have discovered the leak, one last trick wiggle the throttle shaft up and down and to and fro, without rotating the shaft. What you are looking for is excess wear in the carburetor linkage and shaft bushings. IF none of these show you a problem, it is time to consider a mechanic, the problem can be electrical (weak coil) or a mechanical failure beyond a minor repair.
5030
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Sounds like a couple things but I'd start with a gunked up from ethanol carburetor.
Soundguy
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Always check spark first. Its gas n easy.
Next look at that carb and fuel delivery.
To the op.
Pulling the choke IS closing it.
Next look at that carb and fuel delivery.
To the op.
Pulling the choke IS closing it.
crankshaft21
Silver Member
I use to have a 8n ford tractor that did the same thing. Turns out, where the gas line inters the carb, there is a filter in the inlet. The filter was stopped up. I cleaned it and problem solved. You might check that and see if yours has one.
Soundguy
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Oh and remember to check all them vacume lines. It has a bunch.
rjmack
Platinum Member
I have run into this many times, I always start by tightening all carburetor fasteners, manifold bolts, etc. carb to manifold nuts are often the culprit.
not saying this is the issue, but it's a good place to start and doesn't cost you much in terms of time or money.
If that doesn't change anything, I would disconnect the fuel line from the carb and drain whatever comes out into a jar. if you aren't getting much fuel that's a problem, or if its full of water you have another issue. again, cheap and easy in terms of time and money.
not saying this is the issue, but it's a good place to start and doesn't cost you much in terms of time or money.
If that doesn't change anything, I would disconnect the fuel line from the carb and drain whatever comes out into a jar. if you aren't getting much fuel that's a problem, or if its full of water you have another issue. again, cheap and easy in terms of time and money.
rswyan
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After having to clean/rebuild four or five carbs over the last two years that would be the first thing I'd check ... :thumbsup:
Latest one was a carb on Kohler Magnum 18 in a Simplicity CFC 18.
I've had that off the engine to clean it out no less than 5 times in the last 36 hours. Looks to be deteriorated fuel lines (circa 1985 - 87) ... possibly done in by ethanol. Replaced the fuel lines with some Gates fuel injection hose from NAPA after the second or third time I pulled it, still getting crap in the float bowl ... although less each time.
super55
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I believe MF used Zenith carbs which rebuild kits are easily found for them but from the sounds of it you need to do a little bit of carb maintenance. I'm guessing the bowl had a piece of scale break off from it and clogged a jet.
Disconnect the fuel supply line to the carb and see if it runs freely. If it does its not the filter or supply. Open the carb up and clean it. Be sure to to lightly bottom out the fuel/air mixture valve screw and keep a mental note of how many turns it takes so you can get an accurate reset when you put it back together. Usually it rule of thumb is two turns but sometimes people will adjust them when they start running into engines that are running rough so you could be off by as much as 1/2 a turn. If you are hestitant go look on youtube for rebuilding carbs. There is a ton of them on older tractors.
Disconnect the fuel supply line to the carb and see if it runs freely. If it does its not the filter or supply. Open the carb up and clean it. Be sure to to lightly bottom out the fuel/air mixture valve screw and keep a mental note of how many turns it takes so you can get an accurate reset when you put it back together. Usually it rule of thumb is two turns but sometimes people will adjust them when they start running into engines that are running rough so you could be off by as much as 1/2 a turn. If you are hestitant go look on youtube for rebuilding carbs. There is a ton of them on older tractors.
oldpilgrim
Elite Member
I'd bet it's bad gas that crapped up your carburetor. Gas won't last a year without going bad nowadays. Even treating it with stabil, a year is pushing it.
You're going to need to drain all the gas, change any filter, replace with fresh gas and more than likely take the carb apart to clean or replace the jets in it.
Good luck.
