108 V/R? need some help

dieseldan123 · #1 02-17-2012, 11:23 PM

I have a problem with my 108 not getting spark. It cranks and turns easily so nothing to worry about there. I replaced the points and gaped them according to the Kohler manual at .020, turn the key and no white spark from the points. Tested battery and is showing about 12.5v, ran the voltmeter to the solenoid and got same volt reading, went to V/R and still got the same reading. With the key in the ON position the points showed 12.5v, no reading on coil or S/G. When cranking the engine the S/G, coil, and points read about 9-11v, solenoid, and V/R is still 12.5v. So i borrowed the coil and S/G from my 123 and still have a low reading on the points, coil, and S/G, but solenoid continues to have the same 12.5v running through it.

Could it be my V/R not letting enough volts through to have spark at the plug and points? I went through and cleaned the grounds as well, any help is welcomed!

cub1450 · #2 02-18-2012, 12:12 AM

Dan what happens if you run a wire from the battery to the coil.Just to see if it will run and that ought to tell you if its the VR.

dieseldan123 · #3 02-18-2012, 08:49 AM

Thanks Jed Ill give that a try today! hopefully before this crappy weather moves in.

dieseldan123 · #4 02-18-2012, 04:42 PM

Well i tried the jumper method from pos batt terminal to pos side coil and got nothing. Think i have a good V/R that looks exactly like the one that is in there. Ill switch them out and see what happens. My only question is should i polorize or not.

Matt G. · #5 02-18-2012, 05:18 PM

If you bypassed all of the circuitry to the coil by applying 12V to it, and you still don't have any spark, then either the coil, points wire, points, plug wire, or plug are at fault. If the points were new, did you run a piece of paper through them to clean off the oil that is on them from the factory? If not, that may be the problem.

The voltage regulator has nothing to do with this, and if it did, you just eliminated it as being the problem by putting a jumper wire between the battery and coil.

Edit: Would anyone find it helpful if I wrote a "electrical troubleshooting 101" document? It seems like these same type of issues keep coming up time and time again, and having some instructions would probably save myself and others some time typing this stuff up every time someone has a question.

R Bedell · #6 02-18-2012, 05:28 PM

This has been in the Technical Library since March of 2007. PLUS, it is the Kohler Service Manual. A very simple diagram with an average VOM or DVM one could trace down a problem.

Kohler Ignition Circuit

_DX3_ · #7 02-18-2012, 05:31 PM

Quote:

Originally Posted by Matt G.

Edit: Would anyone find it helpful if I wrote a "electrical troubleshooting 101" document? It seems like these same type of issues keep coming up time and time again, and having some instructions would probably save myself and others some time typing this stuff up every time someone has a question.

I think it would be great. Electrical issues for many of us is a painful thing to have to troubleshoot.

Matt G. · #8 02-18-2012, 06:14 PM

Roland-

I'm talking in general, perhaps a decision tree of sorts that someone can follow regardless of whether the problem is the starting system, charging system, ignition, electric PTO, lights, etc. and that would work for both battery and magneto ignition. I just have to be careful not to inadvertently teach everybody how to bypass safety switches.

My goal would be to make it so easy that anybody with no troubleshooting skills and a DVM can go from having nothing happen when the key is turned to having a completely functional tractor after going through the process. I've seen too often where people have been led astray and are checking things that have nothing to do with the problem they are experiencing.

dieseldan123 · #9 02-18-2012, 06:58 PM

Quote:

Originally Posted by _DX3_

I think it would be great. Electrical issues for many of us is a painful thing to have to troubleshoot.

Quote:

Originally Posted by Matt G.

Roland-

I'm talking in general, perhaps a decision tree of sorts that someone can follow regardless of whether the problem is the starting system, charging system, ignition, electric PTO, lights, etc. and that would work for both battery and magneto ignition. I just have to be careful not to inadvertently teach everybody how to bypass safety switches.

My goal would be to make it so easy that anybody with no troubleshooting skills and a DVM can go from having nothing happen when the key is turned to having a completely functional tractor after going through the process. I've seen too often where people have been led astray and are checking things that have nothing to do with the problem they are experiencing.

I completely agree and that would be very helpful to everyone!

Matt that would eliminate many repeat postings for many of our cubs that share electrical systems and those who are not familiar with them. It just sucks that my luck out of the four cubs that i have/owned have had electrial related issues

and appologize for adding to the slew of repeated postings.

BUT! the good news is I did get my 108 running tonight. The problems were: 1. lose wire connection to the F terminal on the V/R. and 2. minior readjustment to the points gaping.

jbrewer · #10 02-18-2012, 07:15 PM

I'm not sure why you didn't have 12V at the + side of the coil (If I read your original post right). So it sounds like you may have 2 problems.

1) Why no 12 v to the coil

and

2) Why no output from the coil when you provide the jumped 12V.

Matt's right, the VR has nothing to do with the problem (certainly not #2)

If it was running before and you changed the points and it's not running, that's where I'd look first...

John