bent crankshaft on mower

[mstng86]

I'm starting to wonder if I have bad gas. I had trouble with my weedeater yesterday too. All gas is from the same source can.

I have tried with breather off and on.. switched plugs. Primed the shit. It hasn't ran in two years, but runs smooth with the carb cleaner.

[ram57ta]

Shocks me that nobody has suggested the flywheel shear pin?
I've replaced tons of them on mowers that had hit various things while mowing. I've even seen a flywheel nut come loose which caused it to shear off from vibration. At the very least a slightly damaged shear pin can cause the timing to to be slightly off and make it run like crap, if its completely sheared off...essentially the flywheel/magneto arent attached to the crankshaft and it won't run at all.

[ram57ta]

I'm starting to wonder if I have bad gas. I had trouble with my weedeater yesterday too. All gas is from the same source can.

I have tried with breather off and on.. switched plugs. Primed the shit. It hasn't ran in two years, but runs smooth with the carb cleaner.

Try some new gas.

[HarrisonTX]

I bet the crank is fine, and the blades are fucked. I'm curious about this little motor now. Try some clean fuel. Siphon that shit from your car and let us know.

[Quadforce]

my grand father made a tool to straighten cranks they get bent regualy. basiclly it is a plate that bolts to teh bottom of the engine and has a piece a square tubing / angle iron welded to it with a bolt that goes thru and you use the bolt to press the shaft back straight. works like a champ

[mstng86]

I give up figuring out why it won't start. Ran new gas, cleaned carb, ran with and without breather, I know it fires since it runs with carb cleaner.

Maybe I need to just get a carb kit and see how that goes. I mean, nothing in life is for free. I had a feeling I would pay for something. Either that, for I take it to a shop.


The funny thing is, I found out the old lawn mower I have is still good. I was just about to look into swapping the carbs and tried it one more time since I never tried it after it cooled off. Put some more oil in it and it fired right up.

[jyro]

did you just totally ignore the stripped flywheel key suggestion

I give up figuring out why it won't start. Ran new gas, cleaned carb, ran with and without breather, I know it fires since it runs with carb cleaner.

Maybe I need to just get a carb kit and see how that goes. I mean, nothing in life is for free. I had a feeling I would pay for something. Either that, for I take it to a shop.


The funny thing is, I found out the old lawn mower I have is still good. I was just about to look into swapping the carbs and tried it one more time since I never tried it after it cooled off. Put some more oil in it and it fired right up.

pull the flywheel off and check the woodruf key. If it's stripped from hitting something or the nut is loose, it will never start.

[shumpertdavid]

pull the flywheel off and check the woodruf key. If it's stripped from hitting something or the nut is loose, it will never start.

Did you totally miss the part about it running on carb cleaner.

OP, I'd dare say you still have something with the carb not right. Remove the air cleaner, use your hand as a choke and try to start it, at the very least you should get your section of hand over the carb inlet wet and hopefully allow it to run. I'd pull the carb off, remove the bowl (make sure that the bowl has gas actually going into it, common sense but just putting down for reference), use carb cleaner with the straw on it to force the cleaner through every ports, hole, orifice, etc. Also go back through all the holes with and air blower.

[ram57ta]

Did you totally miss the part about it running on carb cleaner.

OP, I'd dare say you still have something with the carb not right. Remove the air cleaner, use your hand as a choke and try to start it, at the very least you should get your section of hand over the carb inlet wet and hopefully allow it to run. I'd pull the carb off, remove the bowl (make sure that the bowl has gas actually going into it, common sense but just putting down for reference), use carb cleaner with the straw on it to force the cleaner through every ports, hole, orifice, etc. Also go back through all the holes with and air blower.

runs without the air cleaner on.........this is starting to sound dangerously like my moms old Toro frt. drive rear bagger that had a piece of shit Tecumseh 6.0hp GTS (guaranteed to suck) motor on it. Didn't matter what I did to that piece of shit...the EPA carb had NO jet adjustments available other than idle and no amount of rebuilding could make it run right. I finally found a Troy-Bilt with a broken deck and yanked the 6hp Briggs & Stratton off it and bolted it onto her Toro. It runs perfect to this day and hasn't given me one ounce of trouble.

[mstng86]

Did you totally miss the part about it running on carb cleaner.

OP, I'd dare say you still have something with the carb not right. Remove the air cleaner, use your hand as a choke and try to start it, at the very least you should get your section of hand over the carb inlet wet and hopefully allow it to run. I'd pull the carb off, remove the bowl (make sure that the bowl has gas actually going into it, common sense but just putting down for reference), use carb cleaner with the straw on it to force the cleaner through every ports, hole, orifice, etc. Also go back through all the holes with and air blower.

I did ALL of that. Sprayed every single port, hole, orifice. I don't have a compressor for the air.

I did get some help and my uncle did cover it with his hand with the same results. I am leaning towards the carb just taking a shit. It sat for 2 years so no telling.

[mstng86]

runs without the air cleaner on.........this is starting to sound dangerously like my moms old Toro frt. drive rear bagger that had a piece of shit Tecumseh 6.0hp GTS (guaranteed to suck) motor on it. Didn't matter what I did to that piece of shit...the EPA carb had NO jet adjustments available other than idle and no amount of rebuilding could make it run right. I finally found a Troy-Bilt with a broken deck and yanked the 6hp Briggs & Stratton off it and bolted it onto her Toro. It runs perfect to this day and hasn't given me one ounce of trouble.

This Is the 6.5 GTS Briggs and stratton. I don't see qny adjustments on the carb either. Which is why I am thinking I need a rebuild kit. Putting 25 bucks into this thing won't kill me if it works.

[ram57ta]

This Is the 6.5 GTS Briggs and stratton. I don't see qny adjustments on the carb either. Which is why I am thinking I need a rebuild kit. Putting 25 bucks into this thing won't kill me if it works.

Have you verified consistent spark? Some of those B&S motors have had some issues with the electronic coils going bad. Generally speaking...those B&S motors are pretty damn reliable (far more than the Tecumseh CRAP of a few years ago).

[mstng86]

Have you verified consistent spark? Some of those B&S motors have had some issues with the electronic coils going bad. Generally speaking...those B&S motors are pretty damn reliable (far more than the Tecumseh CRAP of a few years ago).

Not really, but I kind of ruled It out when it consistently fires with the carb cleaner. I did consider that after everything else, but that was pretty late in troubleshooting and I wasnt feeling like digging that deep at that point. I guess it is a possibility if there is no spark after a few cycles.

[jyro]

yes I did

Did you totally miss the part about it running on carb cleaner.

.

I quit reading on this sentence, "I give up figuring out why it won't start".

[crapstang]

If you have the time to swap em more power to ya. Trying the straighten one isn't worth the risk imo. If it breaks and does damage, especially to a human or pet I would feel bad if it were mine. Northern tool has whole engines on the cheap.

It's illegal for shops to straighten them out...some still do anyways.
I know a couple people that have nearly had a limb or two taken off by a mower with a straightened crank failing