I'm trying to fire up a '76 Case 350 which hasn't been run in a few years (and the last time it wasn't by me, so I can't speak for its history or health).
When I hit the starter, the engine turns over for anywhere between half a second and 2 seconds, then the starter disengages from the flywheel and whirs up to high speed: if I hold the start button down it'll keep whirring away till released. Stop and try again and the behavior repeats. Starter sounds reasonably healthy with no odd thunks or grinds.
I've pulled the starter solenoid and it seems OK - there's resistance across the terminals where there should be and the core and high-current switch move freely.
I initially thought it was battery voltage drop, but driving the solenoid directly with a second battery doesn't help. And in any case, if the solenoid wasn't holding, the starter motor would stop when it dropped out.
It also doesn't make sense to be chipped teeth on the flywheel - I'd expect that to lead to nasty noises if it'd stopped in the wrong place last time, and clunking but riding through if the starter encountered it while already rotating. Ditto any other major mechanical fault with the rotating bits - I'd have expected to hear it.
I guess the next step is pull the starter and see if anything else becomes obvious, but the bottom bolt looks like a pig to get to and I don't want to waste hours swearing at it if I'm missing something simple. I know my way round cars but I'm a newbie with heavy equipment, so I may well be.
Any suggestions, anyone?
When I hit the starter, the engine turns over for anywhere between half a second and 2 seconds, then the starter disengages from the flywheel and whirs up to high speed: if I hold the start button down it'll keep whirring away till released. Stop and try again and the behavior repeats. Starter sounds reasonably healthy with no odd thunks or grinds.
I've pulled the starter solenoid and it seems OK - there's resistance across the terminals where there should be and the core and high-current switch move freely.
I initially thought it was battery voltage drop, but driving the solenoid directly with a second battery doesn't help. And in any case, if the solenoid wasn't holding, the starter motor would stop when it dropped out.
It also doesn't make sense to be chipped teeth on the flywheel - I'd expect that to lead to nasty noises if it'd stopped in the wrong place last time, and clunking but riding through if the starter encountered it while already rotating. Ditto any other major mechanical fault with the rotating bits - I'd have expected to hear it.
I guess the next step is pull the starter and see if anything else becomes obvious, but the bottom bolt looks like a pig to get to and I don't want to waste hours swearing at it if I'm missing something simple. I know my way round cars but I'm a newbie with heavy equipment, so I may well be.
Any suggestions, anyone?