Electrical diagnostic process for Exmark LZ31BV604

[CyrusSmith]

Hi all!
I purchased a new wiring harness (part # 103-6568) & starter (forget the part #) to go ahead a rule out those problems. I also have purchased a new parking safety switch (part 1-513051) as well as a key switch (part # 103-0206) and a seat delay module (part # 103-5218) one part I have not replaced is the "tilt switch elimination kit" or tilt switch (part #112-8349, or 1-633782 or 109-4577 depending where you look). I also replaced all the relays.
I hooked up all the new parts and just bypassed (using a piece of wire to sort of "jump" the safety harness if you know what I mean) the safety's for the L and R drive handles and the seat switch, having not replaced these switches I figured bypassing them would help me make sure they weren't a problem. And now I am still just getting a click every time I turn the key switch (which is the same response I was getting with the old harness and parts :/).
1.I might have a bad Tilt switch. I know its part of the safety system somehow and therefore could be causing the engine not to want to turn over. Im probably going to replace this part.
2.(don't even know if this is a thing you can do wrong) I am not sure which was the relays are supposed to be inserted into the harness (there are 3 relays) I put them all in the same way and they fit, but I think they could fit multiple ways---so im not 100% sure they are in there correctly, that could be an issue?
3.Anything else you can think of?

In addition to getting advice based on the info I have provided above on what is the problem and how to fix it I am interested in finding a (relatively) easily understandable break down of how I might do a full diagnostic test on the electric system to determine why im not starting (IE check for X volts at a certain point on the key switch, then Y volts at the next point, etc. etc.) FWIW I am not an electric expert, I do have a decent multimeter but if you have to do anything other than DC/AC volts setting I would really need some detailed instructions on what setting etc. to use to check any of the points I should be checking for power)


Finally, to explain where I am at right now: I get a good "click" at the starter when I turn the key switch, the battery is decently charged but I get nothing else.
Engine won't turn over at all I feel like its some kind of a safety problem (the only thing I haven't bypassed or replaced I think is the tilt switch so maybe that is the issue) but I don't know. Any thoughts?? Thanks all!

 

[bertsmobile1]

Can you manually rotate the engine ?
Lots of things can lock the engine solid from simple bits of magnetic gravel stuck in the magnets to wear in the starter pinion to a dropped push rod jambing the cam shaft to a simple hydro lock .

 

[CyrusSmith]

Can you manually rotate the engine ?
Lots of things can lock the engine solid from simple bits of magnetic gravel stuck in the magnets to wear in the starter pinion to a dropped push rod jambing the cam shaft to a simple hydro lock .

Yes the engine can be manually turned over but that's a good question.

 

[bertsmobile1]

because I am not familiar with your mower . What engine are we playing with and what type of starter does it have ?
Is there a remote starter solenoid or is it a shift start mounted on the starter itself ?
You replaced the starter, does the new one have the same number of teeth on the pinon as the old one ?

 

[CyrusSmith]

because I am not familiar with your mower . What engine are we playing with and what type of starter does it have ?
Is there a remote starter solenoid or is it a shift start mounted on the starter itself ?
You replaced the starter, does the new one have the same number of teeth on the pinon as the old one ?

Hey there! the engine is a Briggs Vanguard V-twin horizontal 896CC Model # 543477-3065-J1
The starter is exactly the same OEM as the one the engine originally had mounted and it does have a remote solenoid. Im not sure of the model # of the starter though.

 

[bertsmobile1]

So arm yourself with a set of jumpers and a known good battery

1) jump from your mowers battery + to the power terminal on the starter motor
Starter cranks the engine = ground connection is good & starter is good

2) if not run a second jumper from the battery - to a good ground on the engine ( oil drain plug works for me )
engine now cranks = bad ground connection
Neither works, the do the same from a know good battery .
Works with the alternative battery = mower battery is duff .

3) If 1 worked, then move the jumper to the starter cable terminal on the solenoid
No crank = bad cable

4) if 3 worked , move the jumper to the battery side & turn the key or jump to the trigger terminal at the base of the solenoid
Engine cranks = bad battery cable
If the solenoid has 2 small terminal at the base , one is + and the other is - so one will need a direct wire to the battery -
If the solenoid had only 1 wire at the base also run a wire from the battery - to the case of the solenoid .
If none of these causes the engine to crank the solenoid is bad

5) check the trigger wire (s)
If you do not have battery voltage on one and ground on the other for a 2 wire solenoid then you have a cranking circuit failure.
What every one seems to have trouble with is understanding that you can switch a ground connection and a almost all mowers use ground switching somewhere in the system.