Safety Switch on control arm and starting

diverjer

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I have a Z248F that has always had some starting problems. Seems to be that switch below the left control arm? If i get mad enough I just use screwdriver across starter solenoid. Sometimes I just lift seat up pull in the left control arm and push in the safety switch button back flat against the base of switch while I turn key and crank engine to start. Most of the time that works. Last summer I replaced the switch and things seem to go fine for months, actually until last week. I can always get it started, but have to do work arounds. Yesterday it just hardly worked at all, I didn't short across starter, but many times of manually pushing in safety switch on lower end of left control arm back to base of switch. And that didn't work every time, but finely did. Yesterday it was very hot, temperature, was 107 and that was real-not feel like temperature. Maybe it was related to temp? Still I got it started and mowed 5 acres.

Today I went to shed for other reasons, and said will let see if it's wants to crank over. Did fine 3 - 4 times in a row- no problems. Drives me crazy!

Tonight I tried something different. I pulled left arm all the way in so I knew it wouldn't crank. Had right arm all the way out like it should be for starting. Then I turned key over so it should be cranking, but I knew it wouldn't as I had left arm pulled in. Then I slowly moved the left arm out until it started cranking over. Was surprised to find I didn't have to go out that far for it to start cranking. I felt where the safety switch button was at and it was not all the way back against the base of safety switch! There was maybe 3/8 inch left that button could have been pushed back further. Plenty of room for me to feel that it wasn't back to the flat base of switch. Now that drove me a bit more crazy, as I mention earlier sometimes I had button all the way back and it didn't crank.

The switch is easy to replace and doesn't cost that much. But my question is has anyone else had this kind of problem? I once had it figured out how to unhook the plug to switch and bypass, but lost where I wrote it down. There are 4 - 5 wires, but only takes a cross between 2, I think one was orange. Anyway, I rather fix it. Thought I come here and see if anyone has had sililar issues and what they did. It has always been on the left side.

Sorry this is sooooo long.
 

Bertrrr

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There should be a relay that reacts to the safety switches, My machine has about 4 I think and they are all the same - if yours has relays like this , swap them around and see if the problem goes away or switches to another area.
 

diverjer

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Will see if I can find any relays tomorrow, can't find them in parts manual (paper version). Found online parts manual for mower and did search, showed it had one 40A part (532 10 97-48), but said not shown in the diagram. Doesn't look like they cost much, if I find it will try a new one.
 

Bertrrr

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mine are under the seat but it's a different machine
 

Tiger Small Engine

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mine are under the seat but it's a different machine
Sometimes the steering arm making contact with the safety switch gets off, and causes the intermittent start problems. Take bad switch and a good switch and test with a multimeter. Make sure that safety switch is held firmly in where it mounts. You may have to find the “sweet spot” to start mower until issue is hopefully resolved. Can be a frustrating process until you get it fixed.
 

StarTech

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Safety switches do become intermittently working due to wear and contact burning.

ANd boy that really looks like a 40A when it is actually a 30/20 amp relay.
 

diverjer

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Took the meter out and tested the switch to see if I remembered how to bypass switch and also to test things. The switch itself has 4 prongs. The plug with wires that attaches to switch has 4 prongs, but 5 wires. Two blue wires on top front go to one prong and one black wire across from the two blue wires on the other. On bottom are two orange wires, one for each prong. The orange wire toward front is hot with key on. Short across the two orange and it cranks fine with handle in any position. No voltage on any of the other 3 prongs.

The two top prongs (the one with 2 blues and the other with one black) will close circuit when the handles are pushed back, open connection when handles pulled in. I don't know what they do, there is not any voltage to them- unless maybe it has to be running. But no voltage with just key on. But they do close the connection when handles pushed back out.

The bottom two, both orange will close circuit when handle are back and the orange one toward front has voltage with key on (regardless of handle position). When handles pulled in the circuit is opened. If I were to clamped these orange wires with a connectors that bites into the wire and hook them together my starting problem would go away. But I will hold off on that for now.

Haven't a clue what those top 2 prongs are for? Might be shutoff if clutch engaged for blades? Still haven't found anything that looks like a relay.

My Gravely (we use two mowers to mow this 5 acres) was smarter. Hand brake on or won't crank and seat switch to cut off blades, controls arms not involved.
 

diverjer

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I should have added all those tests show nothing wrong, that is the way it should work. Also, that is my new switch from last year. Yet there are times it just doesn't work, even when I manually push in safety switch. Then I jump across the solenoid. Another option other than jumping across orange wires would make me a starter button jumping across the solenoid.
 

StarTech

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You have a defective switch or broken wire.

Now this will not make sense to layman.
1] The orange with 12v should drop to zero with the arms out.
2] The 12v is coming from the ground side of the relay. The two lap bars when in the outboard position grounds this relay via the orange. Whenever the relay is not grounded 12v will appear on its ground side leg.
3] The blue wire is also a ground circuit for the starter solenoid when the relay is active.
4] now if either one these ground paths is open the engine will not start.
 
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diverjer

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1] The orange with 12v should drop to zero with the arms out. I tested that out and it does as you said.

When I pull plug out of safety switch my jump across the two orange wires will start engine and even engage clutch and allow blades to run. I turn off clutch as don't want feet to go under deck, just a quick test to see what would run. What seems strange is I pull my jumper off between to orange and engine dies. That seems strange as me pulling my jumper off, is no different than pulling handle back in as that opens circuits( 2 orange wires) and the 2 blues and 1 black were opened when it started as plug was pulled out of safety switch while doing this test and they are all opened anyway when arms pulled in, have tested that with Ohms meter. Now the right arm was out maybe that had something to do with it. Still haven't found any relay.

I am differently a layman on wiring mowers- do much better in household wiring. Them charts are small and hard for my 76 year old eyes to see. But I can always go to jumping solenoid, that hasn't failed. Now however, nobody would think anything was wrong with mower, all working well. If I took it in to the shop Joel would think I was nuts. I should just get another switch, they don't cost much and easy to put on. It may be flaky and like me didn't like the 107 degree heat.
 
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