# Pony needs some giddy-up and go



## me4ble (Dec 20, 2013)

I have a nine year old Troy Bilt Pony riding mower. A few weeks ago, it would not start. the engine would spin once or twice then stop. It would never turn over. I have replaced the spark plug and battery. I have cleaned the air filter. I checked all battery connections and negative cable connection with frame. None of it did the trick. 

Someone told me to pull the plug and hold it against some metal and turn the key. The plug sparked and the engine wanted to start when I did that. However, when I went to pull the rubber boot off of the plug to replace the plug, the metal connector inside the boot broke off and stayed on the plug.

So, I have two questions. Can I replace the connector in the spark plug wire and what can I do to get my pony "trotting" again?


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## Sir Thomas (Dec 7, 2013)

me4ble said:


> I have a nine year old Troy Bilt Pony riding mower. A few weeks ago, it would not start. the engine would spin once or twice then stop. It would never turn over. I have replaced the spark plug and battery. I have cleaned the air filter. I checked all battery connections and negative cable connection with frame. None of it did the trick.
> 
> Someone told me to pull the plug and hold it against some metal and turn the key. The plug sparked and the engine wanted to start when I did that. However, when I went to pull the rubber boot off of the plug to replace the plug, the metal connector inside the boot broke off and stayed on the plug.
> 
> So, I have two questions. Can I replace the connector in the spark plug wire and what can I do to get my pony "trotting" again?


That is not the best way to test a spark plug spark. You can purchase a spark tester at places like Napa. Does this have a Brigg and Straton Engine? What kind of Carburetor?


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## me4ble (Dec 20, 2013)

Briggs & Stratton - How do I tell what kind of carburetor it has?


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## usmcgrunt (Sep 16, 2007)

Hello me4ble and welcome to Hobby Talk. There are literally 100's of Briggs and Stratton motors. Could you post the model and type codes from YOUR engine for more assistance. It sounds like your valves may need adjusting if the engine will not spin over fast enough to start. We could give you a link to the service manual once we know what engine you have.


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## Sir Thomas (Dec 7, 2013)

me4ble said:


> Briggs & Stratton - How do I tell what kind of carburetor it has?


If it has a bowl then it's your typical float valve caburetor. If it doesn't I could be a pulse jet. Does it have a primer or purge bulb on it. Like USCMGrunt says get the model and serial. It could be on the dowing (the part covering the flywheel) next to the fuel tank/carburetor assembly.
http://www.briggsandstratton.com/us/en/support/faqs/how-do-i-identify-a-briggs-and-stratton-engine


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## OptsyEagle (Jul 17, 2007)

A carburetor problem is not going to prevent the motor from spinning when you go to start it. Most likely you have an OHV (overhead valve) motor that needs the valve lash adjusted. It sounds like your motor is "stopping on the compression stroke", which is the main symptom of this issue.

You will need to tell us the model number of the Briggs motor so we can confirm it is an OHV and give you the tolerance spec's and adjustment procedure.


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## me4ble (Dec 20, 2013)

Ok, so it is a Briggs and Stratton 17.5 HP engine - model 31C707. There are other numbers as well (type, code), but this is the model number. Does that suffice?


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## usmcgrunt (Sep 16, 2007)

The type and code numbers would help. When you said it would turn over once or twice, did it just stop turning like the battery was weak?


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## me4ble (Dec 20, 2013)

Type - 0154E1
Code - 040623ZE

I tried a new battery and nothing happened except it may have turned a little quicker, then stopped.


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## usmcgrunt (Sep 16, 2007)

If the engine spins continuously and will not start, then there are trouble shooting steps we can do to help you. IF the engine is only rotating one or two revolutions and then stops, there is a good chance the valves need to be adjusted OR you may have a push rod that is bent or fell off the valve rocker arm. I would remove the valve cover and check the valve adjustment with a feeler gage and adjust to specs.

Here is a link to the service manual for your engine.
http://dl.dropboxusercontent.com/u/12502267/B&S Service Manuals/10_276781SingleCylinderOHV.pdf

Follow the adjustment procedure on page-21 of the manual (all models except 110000,120000). The intake clearance is .003 to .005. The exhaust clearance is .005 to .007. Pay attention to the ¼ inch past top dead center when adjusting so the compression release on the cam shaft is not engaged. Hope this helps.


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## OptsyEagle (Jul 17, 2007)

It is an overhead valve motor and it sure sounds like your valves need adjusting.

Just so you know what is happening. Those motors have so much compression that if the compression release is not working, your battery will never turn it over. It will stop on cranking on the compression stroke. There is a very small bump on the camshaft that opens the intake valve ever so slightly to reduce the compression and allow the battery to crank over the engine for starting. When the valve lash clearance gets too high the compression release does not work and the cranking stops, just like you described.

When you take off the valve cover, the intake valve will be the bottom one and the exhaust will be the top one.


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## Sir Thomas (Dec 7, 2013)

OptsyEagle said:


> It is an overhead valve motor and it sure sounds like your valves need adjusting.
> 
> Just so you know what is happening. Those motors have so much compression that if the compression release is not working, your battery will never turn it over. It will stop on cranking on the compression stroke. There is a very small bump on the camshaft that opens the intake valve ever so slightly to reduce the compression and allow the battery to crank over the engine for starting. When the valve lash clearance gets too high the compression release does not work and the cranking stops, just like you described.
> 
> When you take off the valve cover, the intake valve will be the bottom one and the exhaust will be the top one.


I've never worked with OHC. Wouldn't removing the sparkplug indicate if it's a compression or over compression problem? I misunderstood the description of the problem. I thought he was indicating that it would crank then die. If it cranked and seize then you are right.


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## OptsyEagle (Jul 17, 2007)

Sir Thomas said:


> I've never worked with OHV. Wouldn't removing the sparkplug indicate if it's a compression or over compression problem? I misunderstood the description of the problem. I thought he was indicating that it would crank then die. If it cranked and seize then you are right.


Well, he said that it would stop cranking while he was trying to start it, but when he removed the spark plug "it wanted to start", which I took to mean that it would crank fine when the spark plug was removed. Obviously it didn't actually want to start when it had no spark plug in it, but it certainly would not have any compression to overcome without one, either.

So that tells me that his starter is fine, his battery is fine and the only problem he probably has is that his valve clearance is too high preventing his compression release from working. USMCGRUNT was nice enough to post everything he needs to fix this problem in post #10. No parts needed and maybe 1 hours work if he hasn't done this before, and it should be up and running fine.


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## me4ble (Dec 20, 2013)

Alright, I'll give it a shot this week. I've never adjusted valves before, but it seems to be spelled out pretty clearly in the manual.

I still need to fix the connector for the spark plug. Do I need to replace the whole wire or can I just replace the piece that broke off on the top of the plug?

Thanks for your help!


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## Sir Thomas (Dec 7, 2013)

me4ble said:


> Alright, I'll give it a shot this week. I've never adjusted valves before, but it seems to be spelled out pretty clearly in the manual.
> 
> I still need to fix the connector for the spark plug. Do I need to replace the whole wire or can I just replace the piece that broke off on the top of the plug?
> 
> Thanks for your help!


I THINK you can buy kits at places like Napa, Advance Auto etc. Cut the cable right at the broken connector. Strip the wire covering as instructed on the kit, and slip the new connector on. Clamp it with a plier and then slip the new boot on.

At least that's the way we used to do it. I don't know if it can be done on the new units. Anybody?


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## usmcgrunt (Sep 16, 2007)

SIR THOMAS is correct. A new connector with or without a new boot can be purchased at most auto or small engine stores. Home Depot, Lowe's, and Menards also sell them off the rack near their spark plug selection.


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## me4ble (Dec 20, 2013)

Update:

I replaced the coil and adjusted the valve thanks to your guidance. When I went to start it up, sorry to say that nothing changed. Engine turns once (maybe), then a clicking/grinding noise comes from the starter. Could it be the starter or something else?

As an aside, I have noticed that the oil is a little lower than when I changed it this fall. No biggie, but I just noticed some oily dirt under the valve case when I adjusted the valves. I may change that gasket.


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## Sir Thomas (Dec 7, 2013)

me4ble said:


> Update:
> 
> I replaced the coil and adjusted the valve thanks to your guidance. When I went to start it up, sorry to say that nothing changed. Engine turns once (maybe), then a clicking/grinding noise comes from the starter. Could it be the starter or something else?
> 
> As an aside, I have noticed that the oil is a little lower than when I changed it this fall. No biggie, but I just noticed some oily dirt under the valve case when I adjusted the valves. I may change that gasket.


Does this motor have it set up so you can pull start instead of using the starter? If so, pull to start see what happens. If it pulls then suddenly you feel resistance the you have something locking it up. Can you disengage the drive belt or anything that it drives? Free if up so you can isolate it to the motor itself. When you open it to change the gasket, check the condition of the oil.
Trying to interpret what you mean when you say it turns once or twice. Are you talking about while the starter is ingaged or is the motor trying to start on it's own? if you are saying that the starter turns once or twice then stops you may need to look at the starter itself.


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## OptsyEagle (Jul 17, 2007)

As a test, you could remove the spark plug and see if the starter turns it over freely.


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## me4ble (Dec 20, 2013)

Been a while since I had a chance to mess around with the mower. Went outside yesterday to try to start it up. It seemed like it wanted to start; the starter engaged, then just stopped. It really seems like it wants to start but it just can't make it.


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## 30yearTech (Sep 14, 2006)

me4ble said:


> Been a while since I had a chance to mess around with the mower. Went outside yesterday to try to start it up. It seemed like it wanted to start; the starter engaged, then just stopped. It really seems like it wants to start but it just can't make it.


Check for loose connections at the battery, and make sure the battery is good. You can have them load tested at most auto parts stores, or places that sell batteries. It could be the starter, there is a possibility that your compression release is also not working.


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## OptsyEagle (Jul 17, 2007)

When you were doing the valve adjustment, did you take a look to see if the compression release was working.

With the valve cover off, hand turn the flywheel until the piston passes through the intake stroke and pay very close attention to that intake valve. As it moves on to the compression stroke you will see the valve close tightly and then a very small bump, shortly thereafter. Do you see that bump? If you don't you may have a camshaft problem.

If you do and since your symptoms sound so much like having too high of valve lash on the intake valve, I might even look at reducing the clearance to closer to 0.003" and I might even try 0.002", just to be able to move on from this. As you get closer to 0.000" your motor may suffer from an inability for the intake valve to close completely, messing up your motor's compression. I would just want to see if at 0.002", will the motor crank? If it does and it runs well, I would run with it. If it doesn't run well, I would move the lash back to 0.003" at least.

I had a feeler guage once where the 0.005" feeler was actually 0.008". I spent a lot of time on my valves, one day before I discovered that issue.


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## OptsyEagle (Jul 17, 2007)

Another thought that refers back to your observation that your oil level was a little lower this year.

It's possible that you might have a leak on your inlet valve on the carburetor. Either the inlet needle is not sealing or the float is not floating properly. In either case, gas may be slowing leaking past the carb and into combustion chamber. I have seen this condition not only keep a motor from starting, due to the flooded combustion chamber, but also the hydrolocking resistance this fuel can have on the movement of the piston, can make the motor stop cranking again on the compression stroke.

The time I had this problem. Sometimes it cranked and cranked and cranked and eventually started and sometimes it cranked and stopped on the compression stroke. A simple $10 manual fuel shut off valve stopped the problem from recurring again.

To test for this, I would remove the spark plug and crank the motor over 10 to 15 times. You are trying to blow out any liquid gas through the hole or out the exhaust. When done, reinstall the spark plug and quickly try and start it. If it cranks over, starts or if you even get a few papumps out of it, move the choke back and forth and it should go.

Then install a fuel shut off valve between the tank and the fuel filter. You could look at fixing the carb as well, although the shut off valve is easier and would probably fix this problem for quite a long time.

On this same note. The reason your oil level is important is that this fuel that might be leaking into your cylinder will eventually leak into your oil pan. As it mixes with the oil and as the motor heats up, this gas/oil mix will evaporate quickly, taking a little of your oil with it. 

If it turns out that you have a leaking carb, then you should change your oil immediately, as well.


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## 30yearTech (Sep 14, 2006)

OptsyEagle said:


> Another thought that refers back to your observation that your oil level was a little lower this year.
> 
> It's possible that you might have a leak on your inlet valve on the carburetor. Either the inlet needle is not sealing or the float is not floating properly. In either case, gas may be slowing leaking past the carb and into combustion chamber. I have seen this condition not only keep a motor from starting, due to the flooded combustion chamber, but also the hydrolocking resistance this fuel can have on the movement of the piston, can make the motor stop cranking again on the compression stroke.
> 
> ...


If the carburetor is leaking enough to cause a hydro lock and contaminate the oil, then the oil level is not going to be low. When fuel evaporates, it doesn't take the oil with it. If that were the case the oil would evaporate on it's own. 
Air cooled engines use oil, that's normal and consumption of up to 2 oz per hour is not unusual.


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## OptsyEagle (Jul 17, 2007)

Your probably right. In my case, the leak was occasionally causing a "stop on compression" situation, although most times the motor simply cranked and cranked until I assume that the fuel was expelled and then slowly started to catch and then start. At that time, I confirmed my valves lashes were fine and the installation of the fuel shut off valve, resolved the starting issue completely.

I should add that my motor was still consuming oil after the fix, so you are right on that theory. Obviously the carb leak was not creating this oil loss, so thanks for pointing that out. Not sure what I was thinking there.

I do believe that a fuel leak could be causing his starting problem. Doesn't hurt to check it out.


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## melissaa (Mar 17, 2014)

*ds*

I should add that my motor was still consuming oil after the fix, so you are right on that theory. Obviously the carb leak was not creating this oil loss, so thanks for pointing that out. Not sure what I was thinking there.


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