Engine sounds like a toy machine gun, starter will not engage

pgtips

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  • / sounds like a toy machine gun, starter will not engage
perfect. I bench test wired it up and it made sense.

The round is a small ground and the other wire a +12v to the key.

I have just got it all in bench test situ. Short video of it bench tested and operating correctly.... but not under load > https://photos.app.goo.gl/1DpTBkLqdWpwa4gb9

I think I can concentrate on the wiring, the solenoid and starter appear to be operating correctly ... or am I jumping ahead of myself as its not under load. I guess the next step is to connect it the same as the bench test in the mower to establish if it still works the same or is the load/effort to rise going to be too much.

Can a faulty solenoid lose power to engage the starter?. Im sort of thinking its a go / no-go scenario or do they have an inbetween because I was sure I had 12v measured but I doubt myself now (it was late).
 

dougand3

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  • / sounds like a toy machine gun, starter will not engage
The bench test video looks good. Turns CCW = good. Pinion gear moves outward ~1" = good. It should grab the flywheel teeth. Now, in the first video - I don't see the pinion gear moving outward. Maybe it does and I can't tell. If it does, starter is too low on engine. This isn't a weak starter that can't handle a load issue - at least YET. Starter doesn't have a load until pinion teeth meet flywheel teeth.
 

pgtips

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  • / sounds like a toy machine gun, starter will not engage
I've had success.

I reattached the starter and solenoid, also double checked the solenoid against a heavy duty relay I had, (I don't think these ones have a coil they just switch like a normal relay (1/10th of the price).
Everything was good but when fitted to the mower again it was not working right. I didn't have enough jump leads to add a known good direct to battery lead to ensure a good earth so bought a new battery as mine needed replacing anyway (then this way I didn't need to use my leads to jump the not so good mower battery and freed up my leads).

Cleaned up all terminals and removed/reaffixed the earth cable.

All back together and vroom, started like a champ. Grass cut (2.5 months !).

The annoyance is I really don't know exactly what the problem was but as a suggestion if anyone else has this. I jumped using known good batteries but it was def better using a direct new one.
1. So. Get a new battery if yours is over a year old, not a lot of money and gives you a good start.
2. Take it apart and clean up all the earths and connections. Get some brake cleaner and wash out/clean up your starter.
3. Bench test the starter and solenoid, there's plenty of excellent videos on you Tube (like this one for example) https://www.youtube.com/watch?v=DFPNXq69y6A
* these solenoids are not solenoids in the true sense, they are actually heavy duty relays and a generic one like this https://images.app.goo.gl/uoXWcCHozK8M6ngQ8 will do the job just fine (I tested it) and for a fraction of the price. Obviously you need to refit it differently as its not designed for the starter attachment but its not that difficult. Mine didn't need replacing in the end.
4. If it bench tests out ok, all connections are cleaned and you've put in a new battery then you should be good to go.

My engine was def ok and I had fuel

Thanks for everyones input, it really helped to talk it through.

Kev :smile::tractor:
 
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