safety switch killing batteries

[Fr Anthony]

My six month old Ariens 46 inch has killed two batteries, one brand new. As a friend had a similar problem i think his solution is mine also. Somehow the seat safety switch is killing these batteries. He had to take two new batteries back for replacement before he solved the problem: he disconnected the seat safety switch. On my Ariens the motor was running, the parking brake was set, I stepped off the tractor and the motor died. When I tried to start it up no sound at all...the battery was dead. Anyone else with the same problem?

 

[ILENGINE]

I have never seen a seat switch that was even wired through the battery. They are wired on the kill side of the ignition module, with no battery voltage what so ever even coming close to the seat switch.

I think you need and your neighbor need to look else where for the battery problem. Not charging, faulty batteries, Had a customer that went through 4 one spring due to faulty batteries. Could even be a short some place in the wiring. But I doubt it is the seat switch.

 

[JD is best]

Can you turn on headlights or pto when battery is dead? Seat switch may just be causing you not to be able to crank engine.

 

[Boobala]

I would check the ENTIRE length of the battery cable from the battery to the start solenoid , may have rubbed through the insulation along the frame at some point, ALSO , I had a friend with a similar problem, turned out to be an INTERNAL short, INSIDE his ignition switch, drove him crazy for weeks, could be a pinched wire somewhere too. All the best to ya , keep us informed ........ Boobala ............ :confused3:

 

[motoman]

A battery hydrometer should be purchased ($4). Check the electrolyte. This is a better check than a volt meter. Any auto store. Make sure the rubber beak will enter the battery cells. (Oh yeah, you gotta have an unsealed battery). Do the current drain check if you have a DVM (volt meter). Ignition off. Read DVM owner's manual on how to set up for "CURRENT CHECK." Disconnect ground cable of bat. "Insert" the DVM into the tractor circuit by hooking up one DVM lead to the disconnected bat terminal and the other lead to the disconnected cable. With DVM set on "current" read any value that appears on the DVM . With key off little (milliamps) or no (zero) current should be detected (pros please edit here). Current flow with tractor turned off suggests something is consuming current like a switch stuck on , glove box lite (car) etc. Finding the consumer is the hard part.:smile:

 

[ILENGINE]

amp draw should be 100 milliamps or less. If doing the amp draw test like instructed above make sure your meter can handle up to 20 amps DC, or it may go boom. You will almost always get a 12 v reading if you disconnect one of the battery cables and put a meter between it and the battery post, so you will need an amp test.

 

[Mad Mackie]

On the vast majority of machines, all battery power passes thru the key switch. The key switch also isolates battery power from the charging system when in the off position. The reason being is that the type of charging systems on small engines will draw power from the battery when the engine is not running, therefore the need to open the circuit from the charging system is necessary when the engine is shut off.
What stays hot, is the positive from the battery to the key switch which usually has a fuse of some sort.

 

[ILENGINE]

On most mowers you will have battery voltage to the voltage regulator even with the key off. Most people think you have to isolate the charging system to prevent battery discharge, but if everything is working correctly that isn't true.

 

[motoman]

Thank you gentlemen...So...do the current test. (For readers, expand your capabilities by owning and using a DVM. They can be expensive, but you may get by with a relatively cheap one such as -here I go again- H Frt $25) A word on the current function on these DMVs. The owners manual will show you how to move the test lead(s) to a different socket on the unit from that used for continuity (beep) and voltage. Once set up you can then hook in SERIES with the line to be tested. There is a cautionary note mentioned. Inside the DMV (they come apart) there is a small fuse which will blow in the current function if the fuse capacity is exceeded. The fuse is replaceable. On the outside of the DVM and in the handbook the current capacity in CURRENT mode is stated. The little DVMs only have 2 amp capacity, and the bigger ones typically 10 amps. Don't let this scare you off. These hand held devices will pay for themselves many times over. So in the case of the clutch normally @ 2-4 amps a bigger DVM will read this out when testing. A smaller one may blow the fuse. If the 10 amp version blows a fuse you may surmise the clutch is drawing more than 10 amps , therefore bad. (pros edit please).

 

[Mad Mackie]

On most mowers you will have battery voltage to the voltage regulator even with the key off. Most people think you have to isolate the charging system to prevent battery discharge, but if everything is working correctly that isn't true.

I haven't seen battery excited voltage regulators since Onan and Kohler stopped using them in possibly the mid 70s. Starter/generators have battery voltage at the regulator, but they went away back then also.
AC comes out of the stator in two wires that connect to the regulator/rectifier, the R/R blocks the part of the AC that is the wrong polarity, regulates the part of the AC that is the correct polarity and sends it out a single wire, usually fused and connected to the charging terminal on the key switch. When the key switch in in the on position, it connects the charging output to the battery power in the system.
On higher amp output charging systems, there are differently designed systems, but the majority of the systems 15-20 amps and smaller are the basic type as described above. If battery power is left connected to these systems, power will backfeed thru the R/R and into the stator and attempt to rotate the flywheel and will discharge a fully charged battery fairly quickly and may damage the R/R.