YT4000 Start Issue

[Covy]

One more test. With a 4 terminal solenoid remove the small wire from the small ground terminal on the solenoid and if possible run a ground wire from this terminal to battery negative terminal. If you can’t do this, run this jumper to a good chassis ground. Now repeat the third and fourth tests I posted. If you still have 0 voltage at the large solenoid terminal going to the starter, bod solenoid. I know I shouldn’t do this, but I’m assuming you have also tested the starter by running a heavy wire jumper from battery + terminal to starter terminal and this will turn the engine over?? Am I right??

Sorry for the delay, had my son's baseball to watch last night.

Ran the same test with the solenoid grounded to the negative post of the battery.

First note: Overnight the battery power jumped up such that it was nearly 15VDC (I had the chassis ground pulled from the negative post). I put the chassis ground back on and it went down slowly to about 12.5.

3rd and 4th tests both produced 0V

I also tested with a jumper (not a heavy wire, though):

1. Kept the voltmeter across the battery terminals
2. Pulled the Solenoid wire off which leads to the starter
3. Used jumper (probably 24 AWG) from battery positive post to wire leading to starter - Nothing happened
4. Used jumper from battery positive post to starter post - Nothing happened

Interesting to note that on both tests 3&4 with the starter - the voltmeter would read 0V across the battery terminals as soon as power was put to the starter.

 

[Rivets]

If the voltage across the battery drops to 0V when the key is turned to the start position, then this would indicate a bad cell in the battery. You need to have the battery load tested, a good auto repair shop should be able to do this for you, as I don’t trust the auto parts stores.

 

[Covy]

ok. Since this is a brand new battery - maybe I take it back. Still I wonder about a couple of things:

1. When I move around on the mower (just shift my weight side to side) - I can easily change the voltage almost 2V
2. When the battery has both posts connected (after having the negative-to-chassis pulled) - the voltage drops slowly from 14-15V to 11.x. This suggests some sort of low-level short, right?

 

[Rivets]

Remember we not standing there to see the problem. Personally I think you are over thinking the problem, which is getting in the way of posting a good picture for us to look at. Every time you post a testing result, but doing something a little different when preforming the test, gets very confusing for us. Electrical troubleshooting is difficult enough when we are physically doing the tests, it gets even tougher when we must rely on someone else’s eyes, ears and ability to get to the bottom of the problem. When you keep adding a different result to a test, we must reread the entire thread and then try to see if there is now a different cause than the direction we were going. This almost always results in a misdiagnosis. Each step in the procedure I posted tells us where the possible cause might be. From what you originally posted, my opinion lad me to believe you have a solenoid problem, but now because you back tracked and tested somethings differently, I would look at a battery problem. This now has me very confused, because I don’t know which set of results is the most accurate. I know other techs, with background in electrical troubleshooting, have been watching this post, but don’t want to jump in and make things more confusing, but I’m now asking them to reread this thread and tell me if I am missing something.

 

[Covy]

Sorry about that. I do have an electrical background - so I'm not trying to do things willy-nilly. Admittedly I should have done a better job at testing, my apologies.

Regardless, I performed 3 more tests (don't worry, these will be more insightful):

1. I pushed the mower out, pulled up the Explorer, and used Jumper Cables. I attached the negative to the chassis (and to the Explorer negative post) and the positive I then put on the starter post. The starter works.

2. After this, I reattached all cables and put the jumper cables in typical fashion (negative-negative, positive-positive). No start.

3. Final test, I removed the white wire on the solenoid coil (this is the wire that would go through the clutch and start switch to provide power). Then I ran a jumper from the positive post of the mower battery to the solenoid coil in that position to mimic having the clutch pushed and key turned to start. Starter started. (Tested with and without jumper cables - starter works both ways)


So - since I had previously tested the starter switch (key) and the S&B terminals definitely have continuity when the key is turned, I took a guess that it was the clutch cable in some capacity that was the problem. What I found was that the clutch ground was not secured very tightly, so I took it off, cleaned it up (along with the chassis), and put it back on. **EDIT** That may be the ground to the solenoid coming back to the chasis, difficult to tell unless I take the cables out of the conduit

The mower wouldn't start, but turned over. I used my Explorer to jumpstart and now I will let the alternator charge the battery back up while the motor is running. Hopefully there isn't an electrical short in there of some sort which is draining the battery, but should know soon enough!

 

[Rivets]

You did it again, repeated the same test, but in a different way WITH different results. In your last post, final test, you say you put a jumper between battery + and small terminal on the solenoid. This is the same test you did in step 3 only a different way. Both times you got the same results, battery voltage at the same terminal. Only difference is that now the starter turns over. This is a prime example of why it keeps getting more confusing. At this point I really can’t say what is wrong or whether you may have a bad component. Personally I would say you are back at square one, could be a bad connection, bad component, incorrect testing procedure or a combination of each. I wouldn’t replace any parts until you can verify 100% the cause of the problem.

 

[bertsmobile1]

Been sitting on the edge of this for the exact reason Rivets just mentioned.
And of course I do things a little different which just gets more confusing.
Get some thing with a load like a stop / tail globe .
Hook one side to the white wire to the solenoid the other to a good ground.
Do 100 , not 50 not 99 but 100 start switches and hold the key in start for a minute or so
While you are doing this bounce around in the seat .
If the globe does not light up 100 times or flashes when you are bouncing around then you have a problem in the cranking circuit.
Usually this will be wear in the switches, or the mountings, particularly if they are just a barb pushed though a hole .
If the circuit passed the globe switch, repeat with the globe hooked up between the two trigger wires from the solenoid.
If it fails the test this time your solenoid ground wire is suspect .
If the solenoid ground wire is suspect replace it then try the jump from the battery + cable to the white trigger wire terminal on the solenoid.
If it works then the ground wire was the problem but again you need to do 50 or so cranks to rule out burned contacts on the solenoid