L170 no start - starter solenoid works

[cdretc]

08 L170. 4000 hrs. On some occasions, the skid will not start. I can hear the starter solenoid kick in, but there is no turning over. I removed the starter and it turns over each time on the bench. Battery shows as OK with a tester.

For some reason I'm thinking whether the seat pressure seat could be at fault, but I don't think the solenoid would pull in if it was faulty. Ignition switch? but again why does the solenoid pull in?

Sometimes the skid starts right up. Sometimes, you need to go through 5 or more cycles with the key and buckle. I believe that every time I jumpered it. it always started on the first shot, but it could be a total coincidence and bad memory. And again the battery shows healthy and charged. It is about 5 years old.

Any thoughts? thanks

 

[mrbb]

there should be a starter relay, too, and they can go bad, or just connection to them, and other things get corroded and cause poor power flow, which can be enough to not allow starter to spin
over time, corrosion can build up and casue all sorts of issue
I know My one machine is famous for it happening to it, about every 2-3 yrs, it seems relay and start connections get corroded and doesn't want to start, clean things and back to good, I even coat things with dielectric grease hoping to prevent, but, so far, hasn't seemed to help as it should, ??
as machines just age the wiring seems to just fail on some more than others!

 

[cdretc]

You know that's exactly what I was thinking, that there is a voltage drop in the system somewhere. That's why the starter works fine on the bench but not in the skid. I'll check that relay; it would make sense. Do you know, if it is in the fuse area or whereabouts?

 

[mrbb]

I am NOT 100% but I think it should be in the fuse box

also check your ground wire and positive from battery to starter
it too can have issues with corrosion and cause voltage flow issues that in return mess with starter working properly

Heck, on my one machine, I had issues with a battery disconnect that wasn't allowing full current to pass thru, was only 2 yrs old too, and second one on machine since I got it, seems they don't last long on this machine
as I said, funny some times how some wires and electrical parts fail more on one machine than others, even when used and kept in same location

 

[cdretc]

Thanks for that, but I already checked the main wires and cleaned them up. That relay idea is really good, so I'll try to find that. From the pics it looks quite large (not what I expected). Thanks again for your input. I'll let you know.

 

[haymaker]

Corrosion inside the wires insulation can also cause the starter to not get enough amps to turn over. I have had to trim cables back 3 or 4 inches or replace them before, even though everything looked good.

 

[cdretc]

Oh OK. Good to know. Thanks.

 

[Topper1]

06-2010 models. The starter solenoid contacts burn back just enough to cause the click, click, no turn issue.
If the starter / flywheel gears dont mes (tooth on tooth), the solenoid contacts do not make contact. Starter gets no power & ca not turn.
Add a thin spacer washer to each starter mount bolt.
Spacing the starter away from the flywheel allows the starter contacts to contact & power the starter AS the gears are meshing rather then AFTER they have fully meshed.
Old school vehicle starters came with face shims for this very reason although they were almost never needed.