Bendix & Flywheel

[hgmatt]

So, I was out on the ole lake this weekend, driving back to the gas docks to get some more fuel for the weekend, when the engine just died (another issue that I'm not quite ready to diagnose). Upon it dying, I started it back up with no problems and it ran again for about 5 minutes before dying again. So, I check the usual suspects and can't find anything wrong (think the battery got too low), tried to start it up again & nothing. Heard the starter crank, but the engine would never start up. Got a tow back to the marina and spent the rest of the weekend pouting and drinking. When I went back out to figure out what went wrong, I noticed that the Bendix on the starter was jammed against the flywheel and would never disengage. The only way that I got it disengage was to completely remove the starter from the block, and then the bendix retracted. Any ideas why this would happen?


I have an 89 Bayliner 1700 w/ 85 hp Force that runs great (max RPM is 4900 @ roughly 30 MPH), with a brand new starter (as plastic piece that holds the brushes was broken).

 

[jerryjerry05]

Re: Bendix & Flywheel

If might have stayed up because when the motor fires it's supposed to kick it back out.Motor didn't fire so no kick out.
Why no start???? Check compression(even if it just ran).Then do a spark test.Then check fuel pump. If you have all three and still no start then possible fly wheel key moved.
If you didn't move any adjusting links and all is ok then it should have ran. If you are only running 4900rpm then you need to go down in pitch.Say from a 19 to a 17. Jerry

 

[eurolarva]

Re: Bendix & Flywheel

If starter was stuck in the up "start" position that might be why it died on you . If I am reading your post correctly it sounds like both times you restarted your motor the starter could have stayed engaged to the flywheel. If this is the case chances are your starter is fried.

 

[Frank Acampora]

Re: Bendix & Flywheel

Check for wear marks on top of the round collar right below the bendix gear. If it shows wear, it is contacting the underside of the flywheel at start and jamming.

If it does show wear, then check the top nut on the bendix shaft. That nut holds a collar under which there is a return spring. This collar also stops the upward travel of the bendix. If the nut and collar are not tightened all the way down they will allow the bendix to ride too high on the spiral. This also can jam it in the up position. The collar should be able to slide down the shaft (against spring pressure) with the bendix retracted and you will see the top nut should be contacting a land on the shaft. If you can see the land or you can see the bottom of the threads, the nut is too high. It is a self locking nut so you will need to hold the starter from spinning when you tighten it. If the nut is too high on the threads, the self locking feature is probably worn and you would really want to consider getting a new nut.

BTW: If the bendix is rubbing forcefully under the flywheel this can slow the starter motor. The engine may then turn over too slowly for reliable starting.

 

[hgmatt]

Re: Bendix & Flywheel

Thanks for the replies. From what I experienced out on the water, I think eurolava and Frank have about the right ideas. I was thinking that the bendix got jammed up there after the first start up and stayed, until it caused the motor to crap out. I haven't had a chance to look at it since this weekend, but over the weekend, I had to completely remove the starter from the motor, when I did, the bendix spun right out.

I'll check out those recommendations, but from what I remember, there was no wear on the bendix or starter, I bought this starter about 2 months ago, and have only run the motor for about 5 days total.

As for Jerry, I do agree that the motor should've kicked the Bendix right back out (if it started) and that could be a cause. I think its very unlikely, because, even when I would spin the flywheel by hand, the bendix wouldn't pop down. The force of the spring, in addition to the spinning of the flywheel, should've popped that bendix down. At least that's what I've experienced in the past.

 

[hgmatt]

Re: Bendix & Flywheel

Like a real jerk, I finally discovered the cause to my misfortune with the bendix. As it turns out, Jerry was right on. I finally got a chance to play with it last night, and got the bendix stuck in the flywheel again. My battery wasn't fully charged, so the flywheel was never turned fast enough to start the motor. Charged it right up, and the starter never stuck again. Oh well!

As for the reason behind the motor dying, the jury is still out on that one. I haven't run a decarboning since I laid the motor to rest over the winter, so I decarbed it last night. I'll start a new post for that.

Thanks,

Matt