murray mower won't start

[lking65]

murray model 42544x8a ~ 12 yrs old, b&s mod 310707 type 0113e1 engine

very new to troubleshooting small engines --

mower won't start, only a slight click when the key is switched on, symptoms came on suddenly at the end of last year -- thought battery -- it's been charged and tested ok at autozone -- can trace 12v to base of starter -- can a starter just go bad ? actually it's only 8.83v at the solenoid and the starter -- is that acceptable ? can it be in the switch ? interlocks ??

many thanks -- appreciate your thoughts and suggestions --

larry thomson

 

[SeniorCitizen]

murray model 42544x8a ~ 12 yrs old, b&s mod 310707 type 0113e1 engine

very new to troubleshooting small engines --

mower won't start, only a slight click when the key is switched on, symptoms came on suddenly at the end of last year -- thought battery -- it's been charged and tested ok at autozone -- can trace 12v to base of starter -- can a starter just go bad ? actually it's only 8.83v at the solenoid and the starter -- is that acceptable ? can it be in the switch ? interlocks ??

many thanks -- appreciate your thoughts and suggestions --

larry thomson

I'd like to see the volts just a little higher when the switch is turned to crank/start position but for something to try at no cost remove the spark plug/plugs and see if the starter will crank the engine. If it won't, the pinion gear could be stuck/hanging in the flywheel. If it won't crank with the plug/plugs removed you might consider having the starter tested.

 

[ILENGINE]

8.83 is too low at the starter, should be closer to 10.5 or more. need at least 9 volts to actuate solenoid. Most likely is a bad connection between the battery, solenoid, starter, and ground connections.

First thing to do is connect the black probe from meter to negative post of starter for all test. While attempting to start check voltage from postive post to negative post of battery, should be 12.5v and no less than 10.5 volts. If lower replace battery, Next test is while still holding key to start position touch red lead to battery side of solenoid and check voltage, if below 10.5 then you either have a bad battery wire or bad connection between battery and solenoid. Then put lead on starter side of solenoid is voltage is below 10.5 replace solenoid.

 

[lking65]

many thanks for the replies --

ILENGINE -- where is the negative post of the starter ??

i have replaced the battery -- if i connect the positive battery directly to the starter -- it reacts -- i have > 12v on the battery side of the solenoid and > 12v at the positive side of the starter -- but i am using the negative post on the solenoid as reference -- i believe i get the same readings if i use the battery ground on the frame as reference --

still have the same symptoms -- nothing happens when you turn the key to start --

regarding the seat interlock -- if i disconnect the yellow wire that runs to the switch -- at the in line connector under the dash -- does that remove that interlock from the system ?? or does that cause the interlock to be enforced ??

many thanks

 

[twinfords]

try jumping the soleniod with a screwdriver or plyers, could be bad switch, soleniod, starter etc. you can spin the mower by hand?? also all safety switched contacting?

 

[lking65]

many thanks to all for your help -- problem was the starter solenoid -- the key for me was the resistance across the 2 terminals did not change when the switch was turned to start -- if it is working as a switch -- i'd expect the resistance to drop as the 2 terminals are connected --

disconnecting the yellow wire under the dash did indeed remove the seat interlock -- mower starts whether you are sitting in the seat or not -- i think the problem is in the black connector where the wire comes in from the chassis ground and goes out to the switch -- there is a small microswitch that i think should open the 2 wires when plugged into the grey push switch that responds to the seat -- but it is not -- they are connected all the time -- which is the interlock state -- normally, the grey push switch opens the 2 wires when you sit on the seat -- which is the OK to start state --

learned a lot -- thanks again --

larry thomson