Unit #1 Model 31A607 Type 0741-E1 Code 070326ZE I/C 15.5HP
Unit #2 Model 287707 Type 1224-E1 Code 971009ZO I/C 14.5HP
I do not believe either of these units have an ignition safety interlock issue since both solenoids always activate. Both units have had their batteries swapped out with a known good battery from a working mower, so the batteries are not the issue. I DO NOT know if these two engines have the compression release cams, but I do not suspect this is their issues since the no crank issue is intermittent.
Unit #1 will easily crank and start one day and the next day, try to crank but cannot get past the compression stroke. Multiple days/weeks, same thing then one day it easily cranks and starts right up. Nothing changed, same battery etc. A week later back to not starting because it cannot get past the compression stroke.
Unit #2 is a little different. I have no history. It came to me as a salvage unit to get running and donate to our swim club. It only required a fix to the blade engage interlock switch to activate the starting circuit and get the engine running. Over two weeks of addressing other non-engine issues it started every time. Now all repairs are done, and it is ready to deliver and all I get is the click of the solenoid. (It did sit out in the rain last night.) Swapping out the battery with a known good one produced the same solenoid click only, no attempt to turn the engine over.
I have two questions, first the solenoid. If it clicks and the engine turns to the compression stroke then it is ok, right? If it clicks and the engine does not turn over can the solenoid be bad? Second question is the starter. When they go bad, can they do so on an intermittent basis? Can they work a couple days then not provide the power to get past the compression stroke and then work as usual the next day or week?
