I just brought home a used, but in very good shape, MTD yardman mower. It has the 16.5 hp Briggs mower with the 7-speed shift on the go tranny. It also is the industrial/commercial model. For some reason, the thing will not crank. The engine will spin and gas will go to the carb, but it acts like it is not getting spark. The mower has sat for a few months, but it worked perfectly before the last owner parked it. Where can I start looking to get this machine running? Thanks in advance! Chris

I/c engine right... should be a briggs. Well first off, sat for a few months? I'd clean the carb out, and give it fresh gas... then if that doesn't help, remove the kill wire, it goes to the coil under the shroud, but is easily removed. Is it a ohv, or side valve engine? If removing the kill wire though, gets it going, a switch is bad somewhere. Did you ask why he parked it?

It is the I/c motor... it sat because he was transferred to Ft. Sam Houston for a federal LE job... it has a spark plug on each side of the motor, not sure if it ohv or not... I'll try the kill wire and clean the carb out as soon as this hurricane moves on out... thanks!

This is a pic of the mower...

Ahh, side valve apposed twin, very good engine... well if it sat, for months at a time with untreated gas ( stabil, or any other fuel stabilizer ) its most likely gummed the carb, tank and fuel lines. Since gas by itself with no stabilizer, will sour after a month or so, so if it ran when he parked it, and nothing was wrong, go right to that problem first, the carb ( get a rebuild kit ) soak her good, in cleaner and blow it out with cleaner, you just may get by, with blowing the carb out with cleaner... but that means taking it off, and blowing all the holes out, make sure your getting flow through the lines, ( there is a mesh screen in the bottom of the fuel tank ) that can get clogged. If it has a in-line fuel filter, that can as well... ohh, one thing before you try the kill wire... if dribbling gas, or using starting fluid ( ether) starts it, dead giveaway for a fuel problem. When you get it going, the engine most very well will outlive the mower if taken care of... oh and also check the tank cap holes, to make sure they are venting, gravity feed like these, need that little bit of venting so fuel flow will be right.

What is the safest way to check to see if I have spark to the engine? I have some ideas, some of which are not on the safe side. Thanks again!

Also, where can I find a new hood for my mower? It appears that the previous owner let his german shepherd chew on it a little too much. I have already checked eBay, with no luck... thanks again!
Here is a pic of it...

One way to check, is to take the plug out, put it in the plug boot, and ground the plug to the block, and check for spark, another better way would be to buy a spark tester, one that lets you change the gap on them, ones that light up aren't good. Another way would to let it jolt you :D not fun but works and may tell you... though if it ran before he parked it, just go for the gas problem now... you can always pull the kill wire off the coil, and check later... like I said, a little gas down the carb, if it starts, its all right, keep in mind if the safety switches are still on, you must follow directions, clutch, sit in seat and leave blades off, etc... as for the hood, it's a mtd, if you have a small engine shop around, they may have a couple out there in their junk pile that are still in good shape, that or other places etc, just look around.. though I don't think the hood is at all very important. Just to cover the engine slightly maybe...

All right, I changed the gas filter, installed new lines, cleaned the carb, drained the old fuel out of the tank and cleaned it... now I know for sure that I am getting no spark... I tested the plug with the boot on it, grounded against the block and it was just dead... I pulled the magneto (coil pack) off and there are no numbers on it... I cannot find anything on the web about replacement costs... I am pretty sure the local ACE store will have it, but this is a one-horse town and I'm afraid of the price... where can I get a new coil? I am pretty sure this is the problem because the mower sat out in the weather with the last owner... I could tell the coil had never been changed because it was a pain getting the wire boots to pull through the little hole, like it had not been touched since the factory installed it... any help is appreciated... thanks again

OK, did you try it without the kill wire hooked to it? The coils are pretty simple, ace wouldn't have it I don't think, any small engine shops around? Just simply ask about a apposed twin coil... or magneto. Also before you do so, I believe they are around 20 bucks, could be wrong since it's a twin, but try it without the kill wire, clean up the flywheel and mag, set the coil gap with a dollar bill, till it comes out with some drag but doesn't tear... then spin the flywheel to check for catching... then try... even new plugs... since champions are crap anyway and foul easy.. see if you can find ngk's or autolite in the same heat range... also one thing I've been seeing often in other places... people install the coil upside down... it should say( THIS SIDE OUT ) which means out not towards the engine. And cleaning that rust up will help out with spark... but then again the coil can be just totally dead and won't give up crap, but its good to go through it all before spending some money. Oh and gap those plugs at .30, gappers are pretty cheap to get... I do know ace has those... I also believe their website has a free shipping to the local store near you deal...

I gave up and hauled it off to a repair man, who is a family friend. He is going to get it going sometime this week. After getting it ready to fire, the starter went out. New ones are about $120, which sucks. I do have one question... the mower will not roll freely. The back tires lock up no matter what you do with the tranny and the clutch. Is this normal or is something wrong with the drivetrain?

Well a good thing on the starter, they can be repaired, or replaced with a used since most from other briggs fit right up to it, on that one, it uses a shift on the go? What I'd do is ask him to check the belts, the clutch pulley, basically lets tension off the belt can stick, the pulley itself on the trans can get stuck, or if it gets water in them, stick them that way... that or the trans needs adjusting, and won't go into neutral (n)... if water... well it can be drained ( to get out though ) and unlocked and filled with fresh 80w-90 gear lube. A transaxle is a pretty tuff piece of the drivetrain. Though it sounds out of adjustment? That or the pedal is not hooked up.

It is a shift on the fly 7 speed... how expensive is it once I get into replacing tranny parts? I figure by the time I get this thing running, it will be winter time and I'll have to park it for a few months...

Well for transaxles... you may just find a used one... otherwise you'd have to ask your repair man if he orders parts... what it may be, not certain for a shift on the go, sometimes its just frozen up. Oh and winter time... :D ahh you can get out and use it... just use a multi wieght like a 5 or 10w-30... along those lines... mono grade 30 and you'll end up with damage, since it thickens up, so a 10w-30 for instance, 10 winter- 30, turns into a 10 in the cold, 30 when its hot.

I have an MTD Yardman rider that won't crank. I have changed out the ignition switch because it looked fouled. What else could cause that? The battery is good. The owners manual says it has a fuse, but I can't find it. I also know there are some kill switches on various parts of the machine for safety. Are those easily bypassed?

The engine is a 14.5 hp ohv briggs and stratton. It is the 600 series Yard Machine, if that helps.

Any ideas would be appreciated. I'm at a loss, but I don't know that much about small engines anyway.

Scott

Has it just started doing this? Or was it maybe brought out of storage? Or was a givaway from someone else. Keep the old key switch, they don't look fouled, but they can get worn out or corroded maybe? Anyway, does it make any kind of clicking noise? Make sure the battery holds a charge. There is a in line fuse, should be a 15 blue fuse inline behind the engine around the solenoid, make sure that everything is hooked up as well. You'll see a big module there, with two posts coming out, with one wire from the positive side of the battery, to the starter on the engine, jump that with a screwdriver ( be careful it will spark, so don't have gas open or spilt anywhere ) if it turns over, ( also make sure the key switch is in the on position ) it may be a safety switch, but if the solenoid clicks and clicks while turning the key to start, that sounds bad. And also before hand, make sure the battery connections are clean and tight.

I am helping my neighbor with his Sears 42" mower and we have the same problem. "Clicking" solenoid, it doesn't start. Battery is fully charged, (we put a voltmeter on the input side of the solenoid from the battery, 11.5 volts) we jumped the solenoid from the "hot" post to the post going to the starter and still just clicks. The 30amp fuse is good. According to the wiring diagram, there are also 2 relays in this circuit. Is there a bench test for the starter? I've tested Chevy starters by grounding and putting power to the battery terminal... At this point we're ready to do the R&R of the solenoid for $15.00 at Sears, I hate to get into the old "remove and replace artist" mode like a typical backyard mechanic. I like to know for sure before bolting off to Sears. The starter is $135.00 so we definitely aren't going there yet... Please help oh guru of small engine repair...

Make sure the battery connections are good, tight and clean, and all wires are good, also when you jump the solenoid. Turn the key to the on position and then try, it should at least turn the engine over to start when you jump the two posts. Sometimes it'll spin up and the starter gear will just sit there and click... the starters on these are pretty simple, one wire hookup, its negatively grounded. As for the solenoid if it is fried, ( usually will do nothing or click, even seen them sit there and smoke and pop and sizzle) sears isn't the only place to get them, the mowers are ayp so any small engine shop can get one maybe cheaper.

Thanks for your reply. We replaced the solenoid, it click a hell of lot louder and firmer but still, no starter action. We put a meter on both positive terminals across the solenoid, it transfers 11 volts when the ignition switch is turned to start. Can we assume that the starter is dead?
Thanks, :confused:

Dz

Hmmm, well you can take the starter off to have it tested, take the shroud off and it should be two bolts. You can maybe try to take some jumpers straight from positive to the starter?