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Howdy. First post, so I hope it's in the right place. I don't know if I should post in the repair section, or the brand section.

I'm trying to get my mothers mower going...Craftsman DYT4000, 18.5hp Intek plus. Last year she had a starting problem, and I traced it to a bad starter solenoid. I replaced it with a used one off a parts mower to get through the last month of the season.

So now it's spring, and time to get the mower going, but the solenoid just clicks. I also notice the starter is smoking. I bought a new solenoid, and had the starter tested at the place I get my parts. They say it's fried, so I take the starter off the same parts mower I've got laying around.

I put on the used starter, and the new solenoid, and it still just clicks. Ok, so probably another bad starter. In the process of checking though, I notice I'm only getting 6v (+/-) to the starter when I turn the key to crank it. I've got 12v going to the solenoid, but not coming from it. I switch back to the old solenoid, still the same reading.

I've now very quickly exceeded my level of knowlege with regard to mowers. Any thoughts appreciated.

Either you have a bad connection between the solenoid and starter, or the ground wire from the battery and where it hooks to the mower has a bad connection

ILEingine is correct. I would jump start directly to the starter to confirm, with the parking brake engaged.

I checked earlier, and just now to verify, and this is what I've got...

12.48v at the battery, + to -
12.48v between the battery + and multiple places on the frame
12.48v at the battery side of the solenoid
5.47v at the starter side of the solenoid
5.47v at the starter

I also have continuity between both ends of the cable that goes from the solenoid to the starter. All those numbers fluctuate a little, but I think my battery is getting drained as I keep turning the key more and more to check stuff. I checked a couple hours ago and got readings very close to those.

I tried to jump the starter directly, since I'm only assuming it's bad. Using jumper cables from the battery, I clamped the negative to the frame, and the positive to the post on the starter. It didn't engage, and sparked as if I'd clamped a positive and negative together.

That tells me that the starter is shorted directly to ground. Bad starter? If, the starter didn't spin up and engage. It will give you a good spark when doing this test.

When I had the first one tested and found it was bad, I ordered a replacement. I put this used one on just to see if maybe I'd get lucky temporarily. Obviously it's dead too.

I'll see what happens with the new starter, hopefully tomorrow.

It occurred to me that there was one more check I didn't do....

I'm getting less then 6v at the starter, but when I disconnect the cable from the starter, I get 12v at the end of the cable. When I reconnect it, I only get 6v again.

Obviously something with the starter, right?

You are correct.

I haven't got my new starter yet, but I had a thought....

I've got an 11hp industrial B & S on a water pump, and it's got what appears to be the same starter. I'm guessing there's not much variation. That motor cranks fine, so I pulled the starter and put it on the mower.

Now that it's on the mower, the mower cranks, but very slowly, and not more than a couple revolutions. It seems that compression is overpowering the starters ability to crank. If I let it sit a minute, it cranks again, presumably after compression has bled off. However, it still only cranks a couple revolutions again.

I'm lost. Again. Any thoughts appreciated.

For what it's worth, this mower ran fine last year, but it has now been sitting for 7 months. Also, the battery is new.

Try removing the spark plug and seeing if it will spin easily. Also, make sure that you have a good 12V at the starter.

wow, not to hijack your thread, but this same problem has been bothering me the past few days. I'm getting roughly the same voltages as you at the same locations. After getting roughly less than 5v on the starter side of the solenoid and same at the starter i was assuming it is the solenoid that was bad, and my motor spins freely once the spark plug is pulled and i checked my valve clearances and they were in spec, so idk either....:confused3:

MJ, with the spark plug out rotate the engine by hand and watch carefully to see if one of the valves jumps slightly just before TDC. We need to check to see if the compression release is working.

I'm pretty sure I've got it figured out. There were multiple problems.

First, the starter solenoid was definately bad. Also the starter. I put in a new solenoid and a good (though used) starter. It cranked, but slowly, which I couldn't figure out because the battery was new.

As it turns out though, the new battery my brother had bought was only a 200 amp, which didn't have enough juice to crank the 18hp motor.

I put a 285 amp battery in it and it cranks fine, but still wouldn't start. I pulled the fuel line and found no fuel flow when cranking, so I'm assuming a new fuel pump will finally make it run. Haven't got their yet though.

Before you buy a new pump test it by removing the fuel line to the carb and turn the engine over. If no fuel comes out the line, either the pump is bad or the pulse line. Is bad. Pulse line should be checked for cracks and/or air leaks.

I'll check the line. My mower shop guy is pretty good though...he's not out to just sell me parts. He also suggested checking for fuel flow. When I pulled the line off, there was no flow at all.

If the pulse line looks good, you'll probably looking at a new pump.

Well, I spoke too soon. It cranks great now, but still won't start.

I replaced the fuel pump....no start.
I bypassed the fuel filter....no start.

In the process of replacing the pump, fuel began flowing from the tank when I pulled the line off, so it's obviously getting fuel to the pump.

The line from the pump to the carburetor is new....came with the pump. The line from the pump to the oil fill tube seems good. I blew through it to check for blockage, and blew into it with my thumb on the other end to check for leaks. Nothing. Just in case, I swapped it with the old hose that went from the pump to the carb, and the mower still didn't run.

I'm so close that it's become even more frustrating. The electrical issues are worked out, and it starts right up and runs fine for a few seconds when I pour a little gas into the carb.

Any thoughts on why it's not drawing fuel on it's own would be much appreciated. I'm totally out of my element with mowers.
:mur:

Thanks

Two things. Have you checked to see if you spark, I'm assuming yes. You said that the pulse line comes off the fill tube. Is the fill tube cracked? Also, does the dip stick fit tightly? Both of these could cause low crankcase pressure. I can't remember, have you sprayed some carb cleaner into the carb air horn to see if it will start that way? Some things to check.

It's got spark, and does run with gas poured in the carb. I'm assuming, based on your suggestions that the fuel pump works off vacuum pressure from the oil fill tube. It is loose currently. I got tired of putting everything back together, then taking it apart again when it wouldn't start, so I've got the top shroud off while I'm working on it. The shroud is what holds the oil fill tube tight in place.

Could be as simple as just putting it all back together completely I suppose. I may end up feeling really dumb, but hey, if it runs, I can live with that.
:biggrin:

Thanks for the suggestions.

Yes, you need that tube to be snug and tight, no air leaks. Sorry I didn't think of this before. Old age is setting in I guess.

I'm ready to just shoot it.

Can somebody tell me how the fuel pump is supposed to work? If I pour gas in the carb, it runs for a few seconds, so obviously I've got spark. If I disconnect the line from the fuel tank to the pump, I get fuel flowing, so it's obviously got fuel to the pump. And the pump is new.

If I pull the hose off the oil filler tube, I've got suction there when it cranks, but there is no fuel at the carb when I pull that supply hose off.

So I'm confused as to how this fuel pump is supposed to work. I've got fuel to it, and suction to it, but no fuel coming out of it.

What am I missing?

Do you have both suction and pressure in the pulse line? Can you hook up some sort of gravity feed system to the pump, so that it doesnot have to work to hard to get fuel to the carb? I use a small funnel and a piece of fuel line held right above the pump. You may have gotten a bad pump????

The starter for the 11hp likely does not have the same amount of windings as the mower had. Not enough 'azz'. Just put the new starter on and be done with it.

If the starter bolts on it has the same number of windings. B&S only changes the winding when they change external design. Don't change starter again. I've just reread your posting and something came to mind. Are you sure that you have the fuel lines connected right? There is an inlet and outlet. I know it's a dumb question. Would you try this test. Take a piece of fuel line, attach it to a small funnel and to the fuel inlet on the carb. (Plug the line from the pump). Put some fuel in the funnel and try to start the engine. What we are doing is building a gravity feed system to test the carb. If the engine starts and runs we know that the pump is the problem. If it does not run we have to get the carb right before looking at the pump. You may need a third and fourth hand to do this test.

OK, it's been a while. Other things got in the way of progress.

Just to update, for those who may be searching in the future, the mower is running. I had been hoping to get this running for my mother (her mower), but just couldn't figure it out. So, it went to the shop. It had a new starter, new fuel pump, and I had removed every ground connection and cleaned them.

As it turns out, the shop tells me the carb was all gummed up. It also needed both blades, a new belt, and they're saying it still needs new drive pulleys due to rust. I was discussing this with my brother and he tells me about how she left the mower sitting outside, uncovered, for about 7 months this past winter. Here in Washington, it's known to rain a little, and the past couple years we've had ridiculous (for us) amounts of snow.

So, moral of the story....

If you let your mower sit outside in the weather for half a year, you might have problems. In this case, it cost my mother $257 at the shop to get her mower going, plus $25 for a fuel pump, and $120 for the starter we put on it (which it needed anyway, but probably wouldn't have if it was stored properly).

Thanks for everybodys help. I appreciate it.
:thumbsup:

mudpie said:

I haven't got my new starter yet, but I had a thought....

I've got an 11hp industrial B & S on a water pump, and it's got what appears to be the same starter. I'm guessing there's not much variation. That motor cranks fine, so I pulled the starter and put it on the mower.

Now that it's on the mower, the mower cranks, but very slowly, and not more than a couple revolutions. It seems that compression is overpowering the starters ability to crank. If I let it sit a minute, it cranks again, presumably after compression has bled off. However, it still only cranks a couple revolutions again.

I'm lost. Again. Any thoughts appreciated.

For what it's worth, this mower ran fine last year, but it has now been sitting for 7 months. Also, the battery is new.

Click to expand...

I have been battling the same problem with one of mine -a Yardman. It seemed that the crank couldn't overcome the compression. I put new brushes in the starter ($20 as opposed to $140 for new starter). The ground for the starter was missing so added that ($3). This helped but still hard crank. I then changed the cable from the solenoid to the starter to a larger cable than the original. This seemed to resolve the issue and the mower starts every time now. Just a thought if anyone else runs into this oddball behavior with their mower.