Riding mower doesn’t run.
#1
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Riding mower doesn’t run.
I’ve been getting it running off and on over the last few years. It’s never ran great though. I had another thread about it but figured I’d start new on it due to than one being on going over a few years and I feel like I accidentally explained the symptoms wrong.
its a MTD 17.5ohv 42” cut mower. I’ll post pics of infor next.
ive put two new carbs on it. I’ve had it running and sprayed carb cleaner looking for intake leaks and there are none. It has great spark. Carb is clean. When running it doesn’t smoke. I’ve adjusted the valves as best I can. I’m new to adjusting valves. It has great fuel flow through the hose to the carb.
What its doing.
It it will start but only run on choke. When I put it on run it dies. It does run better when warm and I can get it to run after starting it a few times and once it’s warm it will run but it’s horrible and after a min or so it dies. I have to constantly change to choke and run to keep it running. Running has nothing to do with the blades or driving because I took the belts off and it is still the same. It’s something wrong with the engine. It seems it has compression because it’s hard to tun the engine by hand past compression. It’s not too hard to turn by the starter though. The mower has maybe 100 hours on it. Was not used much. It did sit in a shed for 2 or so years without being used. It has ran ok after it sat for those years but it’s only gotten worse over time. It’s slowly gotten worse. Starter turns the engine fine. The carb has an idle screw and when I adjust it, it does nothing to change idling. I feel that means something. That may help someone help me.
i know it’s running lean due to running better on choke.
What would make it run lean? I feel like I’ve done most things.
Could the head gasket be bad? Could a bad head gasket happen and the engine not smoke?
ive heard that the cam can wear out. How can I check that?
Im determined to fix this thing. I will not give up on it. I’ve been working on it off and on for a few years and I may sound stupid keeping working on it but since I’ve worked for so long I’m not going to give up now.
its a MTD 17.5ohv 42” cut mower. I’ll post pics of infor next.
ive put two new carbs on it. I’ve had it running and sprayed carb cleaner looking for intake leaks and there are none. It has great spark. Carb is clean. When running it doesn’t smoke. I’ve adjusted the valves as best I can. I’m new to adjusting valves. It has great fuel flow through the hose to the carb.
What its doing.
It it will start but only run on choke. When I put it on run it dies. It does run better when warm and I can get it to run after starting it a few times and once it’s warm it will run but it’s horrible and after a min or so it dies. I have to constantly change to choke and run to keep it running. Running has nothing to do with the blades or driving because I took the belts off and it is still the same. It’s something wrong with the engine. It seems it has compression because it’s hard to tun the engine by hand past compression. It’s not too hard to turn by the starter though. The mower has maybe 100 hours on it. Was not used much. It did sit in a shed for 2 or so years without being used. It has ran ok after it sat for those years but it’s only gotten worse over time. It’s slowly gotten worse. Starter turns the engine fine. The carb has an idle screw and when I adjust it, it does nothing to change idling. I feel that means something. That may help someone help me.
i know it’s running lean due to running better on choke.
What would make it run lean? I feel like I’ve done most things.
Could the head gasket be bad? Could a bad head gasket happen and the engine not smoke?
ive heard that the cam can wear out. How can I check that?
Im determined to fix this thing. I will not give up on it. I’ve been working on it off and on for a few years and I may sound stupid keeping working on it but since I’ve worked for so long I’m not going to give up now.
#3
First, are you still running old gas ( 2 years old) to the carb? Second, when was the last time you cleaned and gapped the spark plug.? Third, how did you reset the needle valve(s) on the carb.
Stick to the basics, I doubt a major overhaul is In order.
Stick to the basics, I doubt a major overhaul is In order.
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Gas has been drained and is new. Has new fuel filter. I don’t know when I last got a new spark plug. I’ll get one tomorrow. There is only an idle adjustment for the carb. I tightened it in slightly with very little pressure and then turned it out 1.5turns. I did not tighten it too tight at the bottom.
It’s a China carb. It’s the 2nd China carb I bought new for it. They both changed nothing from the original carb.
I am going to try to set the valves again. I’m thinking I didn’t do them perfectly. I watched some more videos on setting them.
It’s a China carb. It’s the 2nd China carb I bought new for it. They both changed nothing from the original carb.
I am going to try to set the valves again. I’m thinking I didn’t do them perfectly. I watched some more videos on setting them.
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I bought a new spark plug yesterday and a new feeder gauge. Hopefully today I have time to set the valves and put the new spark plug in.
Am I right in setting the exhaust at .004 and intake at .006?
Am I right in setting the exhaust at .004 and intake at .006?
#8
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I would purchase a compression tester and test to verify acceptable operation of the valve train. If the compression is OK, I would adjust the carb. The carb has two adjustable screws for adjusting gas flow at low and high speed. Since the engine manufacturer doesn't want you adjusting them, they usually have a collar around them and require a special tool to turn. The special tool can be purchased from the web or there are home grown tools that will do the job. Search the web. If the screws are not identified by L and H on the carb body, the low speed adjust is usually the one closest to the engine. Good luck.