# Lawn Tractor Starter Issues



## Euclid34 (May 5, 2014)

I have an MTD/Yard Machines 42" (2003) that I picked up which needs some rehab. I replaced the battery a week ago as the previous one was dead. After the replacement, it started right up. However, last night I tried to start her up and it would crank, but not kick over. I tried several times to no avail. Suddenly, it wont crank at all and it doesnt seem to be getting any power at all. I tried again this morning and nothing. I had planned on checking out the spark plug, but since the engine is not turning at all, I dont think that is the issue... although that may be the reason why it wasnt turning over.

I didnt have a chance to swap batteries, but as far as I know as an amateur, I doubt that is the issue since the battery is a week old and I didnt really over-do it when trying to turn over the engine.

Anyone have any thoughts that might point me in the right direction of a solution? Much appreciated!


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## Euclid34 (May 5, 2014)

I am wondering if this could be a fuse issue?


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## jhngardner367 (Apr 5, 2011)

It could definitely be a fuse ! Check for the fuse by back-tracking the main feed wire to the switch. You should see the fuse holder. Some models have them under the dash,and others have them under the shift plate


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## Euclid34 (May 5, 2014)

i pulled the fuse and it doesnt look blown. it also showed resistence with my cheap multimeter.

Interestingly, I pulled the spark plug and it was beyond dirty. LOADED with buildup, the ugliest plug I have ever seen! It explains why the engine would not turn over and I am shocked that I was able to get it up and running at all last week.

I am concerned that with the multiple attempts to start it, I may have caused more damage... why would the engine suddenly not get any juice? 

My plan is to get a new plug and a fresh fuse and try again tomorrow. If that doesnt work, I did read somewhere that you can bypass the starter my jumping the + terminal directly to the starter assembly on the engine. I have no experience in doing this and I dont want to further damage the engine, however I realize this is a useful tool in diagnosing the problem.


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## Euclid34 (May 5, 2014)

I was able to jump past the starter and the engine cranked. So it must be an issue with the ignition/solenoid... 

I will take a look at it later tonight and post an update afterwards.


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## Euclid34 (May 5, 2014)

I replaced the solenoid upstream of the starter and no dice. I do notice that when I turn the key half way, but not all the way to crank, I hear one click. I traced this to the fuel bowl solenoid. I think that this means I am getting juice in the system, but the starter is still not cranking. 

I also replaced the spark plug and the engine will still not turn over when I bypass the ignition. It cranks just fine. This makes me think that the starter is ok, but I am no expert.

This issue has certainly baffled me... im running out of ideas!


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## film495 (Nov 1, 2013)

I doubt you did any damage, but if you think it is an issue as you work on it, you can put a few drop of oil in they spark plug hole to lube up the cylinder. Don't crank the motor too much without letting the starter motor rest, I believe it is possible to overheat a starter motor. 

Your switch may be bad, or there could be a bad connection there. If your decent with the multimeter, check the connections on the back of the starter switch to see if there is power at the right spots (especially from the starter switch to the starter solenoid), you could use one of those little test lamps too. 

If you can jump to the starter and get the motor to turn over, but not fire - and you've replaced the solenoid, I would guess you're not getting power from the switch to the solenoid to activate it when you turn the switch to start. Try figuring out which wire does that and see if there is a bad connection loose wire. You should be able to figure out which wire goes from the start switch to the solenoid, either by tracing it or looking at the colors and doing some detective work.

I'd fix this first and worry about the not firing up second. If you can get the motor to turn on the switch, then take the plug out and place it against the frame of your machine and watch the spark if there is any. If there is none, check the connections to the coil, I one time had the plug wire was just not attached at the coil correctly. If you do have a spark it should be a nice blue snappy spark, especially on a new plug.

Since your plug was fouled I'm going to guess you have another issue in there that was causing the plug to foul badly. It could just be that whatever is causing the motor to not fire was causing weak spark and not burning all the fuel mix; if it is the same thing you are lucky and can kill 2 birds with one stone.

Seems like a lot of stuff, but it isn't really that hard, and if you are persistent enough to keep figuring it out, you'll know your machine really well and will be more able to work through any issues that come up when you're using it; or need to use it. I honestly don't like working on my machine, however - I find it very rewarding after the fact when I've fixed something or worked through a problem.


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## Euclid34 (May 5, 2014)

Thank you for the detailed reply Film495! I agree... get the starter working and then deal with the engine firing. Your suggestions are extremely helpful!

After my last post, I went back outside and messed with the ground and inspected the ignition switch. I disconnected the harness and took a look at the ignition and cleaned the posts a little bit with some sandpaper. After that, I was no longer getting the click at the fuel bowl solenoid... so I am confident that it is a switch issue. It was too late for me to do any diagnostics on it, but that is my plan next. It makes sense to me that the ignition switch could be partially compromised and allowing juice to flow to the fuel bowl, but not to the electric starter.


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## Euclid34 (May 5, 2014)

I am not an electrician in the least, but I took a look at the electrical diagram on the MTD website for my model and it looks like there are 2 fuses in the circuit? I only found one, next to the starter solenoid beneath the seat. I was not aware of a 2nd, unless I am not reading the diagram correctly.

Not sure if this link will work properly, but here is the diagram


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## jhngardner367 (Apr 5, 2011)

The diagram shows one fuse,between the starter solenoid,and the switch(20a) another from the battery neg(20a) to the headlight neg(green wire).
The one for the lights won't affect starting.
Make sure you have power at the solenoid-side of the fuse,and if so,and it still doesn't crank the engine,then you need to check safety switches(seat,PTO,deck,shifter).


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## film495 (Nov 1, 2013)

If I were you I'd spend some time with the multimeter or test light before taking time to muck with anything. Basically, you have no power getting to where you want it. Spend a little time looking over which terminal on the switch has power in the off position, run position, and start position. The wire that sends power to your solenoid will likely have an S marked on it, when you turn the key there should be power there if not you either have a bad switch or a safety switch is having some fun with you. 

If you are adventurous and comfortable with electricity and wear gloves and safety glasses, it is possible to put one alligator clip on the S terminal on the starter switch and another alligator clip wire on the B terminal. then if you touch the other two ends of the wires/clips together, you're basically bypassing the switch. I ran my machine for a few weeks like this once. If your solenoid is good and your starter is good, this will make the machine turn over, if you do it with the key in the run position you might get lucky and it could start. 

If your not comfortable with electricity do not do this. I was working on my switches this winter and made a mistake and literally ran away from my machine as I was melting wires and clouds of electrical fire smoke came pouring out of my machine. It ended up not doing any permanent damage and nobody got hurt, but electricity is a dangerous thing and easy to make a mistake, so safety first. I won't touch it without gloves and safety glasses.


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## Euclid34 (May 5, 2014)

Before I saw your post Film495, I tried trouble shooting the safety switches by connecting the multimeter to the wire going to the ignition and completing the circuit by touching the other wire to where the wire from the ignition connects to the solenoid. I looked for power and then disengaged each safety feaure (Brake, Seat, Blade engage) and made sure power no longer came thru... everything checked out. 

After I had verified getting power, I reconnected the ignition to the solenoid and turned the key to start... i heard the normal click at the fuel bowl, but also heard a click at (or near) the starter solenoid. I then reconnected the multimeter and now was not getting as much power showing... actually a fraction of the usual 12+V. Am I to assume I messed up the starter solenoid some how by trying to turn it over? Is there something I should investigate that would cause the solenoid to break? This was a brand new universal solenoid. 

I should also mention I was not the original owner of this tractor, and I noticed (when I first got it running) that the seat safety switch doesnt function properly... the engine runs even when the switch is engaged (ie i am not sitting on the seat). I dont see any visible "jumping of the seat switch, as the wiring is properly connected to the tabs.

I am also somewhat confused on your suggestion on jumping the ignition... there are not any S or B designations on the solenoid... but I assume you mean to basically connect the two larger (not the ignition and starter tabs) posts of the solenoid.


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## Euclid34 (May 5, 2014)

So I should mention that I went back out after about 45 min or so after I heard the solenoid click and was no longer getting the full juice when I would put the ignition in start... I checked to see, after the 45 min rest, and I was again getting the full juice. I reconnected the ignition to the solenoid and heard the solenoid click again and like the last time, full juice was no longer going to the solenoid.

I feel like something is faulty and causing the solenoid to not function properly. Hopefully this will be useful in assisting me diagnose what the issue may be!

Also, it seems to me, that your suggestion of connecting the two large posts on the solenoid is basically the same as jumping directly to the battery... is my reasoning correct that it would test the integrity of the wiring from the starter to the solenoid, but not the integrity of the solenoid?

I appreciate all the input! Im determined to figure this out, even though I plan on flipping this machine once I get it up and running safely!


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## film495 (Nov 1, 2013)

no, I meant to jump the starter switch to test if it is bad. usually there is an S terminal and a B terminal. jumping this would have the same effect as turning the key to start if you do this with the key in the run position. you'd just be completing the circuit the switch should be completing, but doing it manually. those large terminals on the solenoid have a lot of power and I never muck around with them personally because I think it is too dangerous for me; I won't touch them unless the battery is disconnected, and can't suggest anything different.

sounds like you have a bad connection somewhere, or bad starter switch. I'd bet money on a bad connection. just keep checking for the correct power with the multimeter and backtrack to see where you're dropping out. if you're not getting the correct power at the solenoid to activate it, check the same thing at the wire where it connects to the switch, also check the live battery power that comes into the switch with the exact same conditions. If the correct power isn't passing through the switch, you can jump across the starter switch terminals to test the rest of the system. If it turns the motor with a jumper wire, then you either have a failing switch or a bad connection there. If that is the case, redo/check the connections to the switch and solenoid, and try again. If it is the switch and you test the connections, my next step would be to swap out the switch. It is probably a bad connection though, I'd disconnect the battery and then disconnect and clean the connections, looking for a ben broken wire near the ends of the wires, you might find one that is bent or was bent near the end where the wire is attached to the connector, if you find one that looks bent just replace the connector. Go through them all, I'd also just since the battery is disconnected, clean up the battery terminals, clean the ground where the battery wire connects to the frame, and put the battery on a charger for an hour or so while you go over those connections.


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## ftorleans1 (Jul 12, 2009)

As if you haven't received enough suggestions yet, The safety switches could be playing with you. Also, when you jumped the starter straight from the battery and the engine cranked but no start, did you have the ignition key on? You can force a starter to spin the engine(by straight jumping) however, If the ignition key is in the off position, you ground out all spark from the ignition system. DON'T LET THIS BEAT YOU! Eventually, You will track down the problem!!!


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## Euclid34 (May 5, 2014)

I have good news! PROBLEM SOLVED!

Turns out, the positive battery cable was damaged. I removed it, replaced it, and she started on the first turn. The cable was not destroyed, but not in good shape... which explains why I would occasional not have current flowing at the different switches. Enough juice was flowing to trip the fuel float solenoid, but not enough at the starter solenoid. My issues with starting her up was probably solved with the new spark plug... and the start up issues with the old one probably lead to the demise of the batter cable due to heat while trying to crank.

Regardless, the issue is solved and boy do i feel good! I noticed several other issues once I got it started.

1. prior owner must have fiddled with seat safety switch because it will only crank when NOT sitting on the seat, obvious issue with the switch but i didnt have time to look at the wiring.

2. Drive belt seems to be on there somewhat loose... if I observe thru the FND control panel hole, it almost looks like its wobbling a bit... perhaps he has wrong belt on there... again, i need to investigate further.

3. significant white-ish smoke from engine while running... this is kind of a scary issue as i have no experience, or really any desire to take the engine apart. my plan is to change the oil and filter and hope that clears up the issue.

Those problems are probably worthy of another thread and ill probably start one at some point... but I wanted to thank you all for the input, was incredibly helpful in giving me the confidence to jack around with the tractor! what a great community here!


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## Howjame (May 20, 2014)

I have an mtd gold, 46", 20hp I believe. It's been running fine, until I boosted my van with it while the mower was running ( not the smartest, or the dumbest thing I have ever done) now I have no power at all, have I blown a fuse or worse?


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