Flywheel bolts

[Old Koreelah]

sounds like starter windup should be ramped instead of whacked. easily done.

I'm very interested in that fix. As posted elsewhere, my Lithium battery is very gently on the flywheel bolts when starting from cold: cranks very slowly (as if battery is dead) and then increases speed until it fires.

Starting when hot is almost violent, so it needs a "ramp-up" fix.

[RFguy]

There are a few techniques for controlling series/parallel motors. Ramp up over 3 of seconds would do it. Could be super simple. When I get my Jab , I'll look at this.

[facthunter]

The usual mechanism requires a quick "hit" to wind the pinion into engagement on a helix.. IF you wind it up slowly it will probably stay where it is or not fully engage and chew out the ring gear. I prefer the manual cable pull or a solenoid where the pinion meshes and then power is applied. The "inertial" type is not really suited for ANYTHING let alone a Jab flywheel. Nev

[RFguy]

that's right - depending on how the pinion is engaged. as you described, the pinion solenoid needs to be powered separately from the driving winding. On one starter motor I saw, (motor vehicle) the pinion was engaged by a wound up shaft when the starter began to move. (no pinion push solenoid) .

 

I have a Cirrus (Lycoming 360 ) starter motor here (dead one) . I will take a look how they are built.

[facthunter]

They appear to be quite different. If the battery goes flat while cranking they stay engaged with the gear even of you turn the prop and are ruddy heavy. As soon as I installed a new fully charged battery all was fine. Nev

[RFguy]

They appear to be quite different. If the battery goes flat while cranking they stay engaged with the gear even of you turn the prop and are ruddy heavy. As soon as I installed a new fully charged battery all was fine. Nev

do you think it stayed engaged just because it was engaged and friction with the ring gear held it there against some pressure/resistance ?

[facthunter]

No, I rang my Lame and he said they said they do that and it's normal. I was a bit sceptical but he knows his stuff. There's also back lash with the ring gear. Easy to check. The starter is quite bulky on the drive end so I think there's something fancy in there . Might be to do with what we are talking about, Nev

[RFguy]

OK thanks. well, might have to muck around with it to understand it.

[facthunter]

Driving accessories from a case of gears on the rear of an engine is nuts. Any damage and something drops into the engine and damages it. You can't beat a V belt for driving a gene or alternator. They live longer than with a harsh gear drive. Nev

[Thruster88]

that's right - depending on how the pinion is engaged. as you described, the pinion solenoid needs to be powered separately from the driving winding. On one starter motor I saw, (motor vehicle) the pinion was engaged by a wound up shaft when the starter began to move. (no pinion push solenoid) .

 

I have a Cirrus (Lycoming 360 ) starter motor here (dead one) . I will take a look how they are built.

That would be a little six cyl Continental IO-360 in the cirrus sr20, the starter drives into the rear case.

[RFguy]

via a slotted shaft extending from the starter motor case.

[facthunter]

I'm only speaking of the ones that have a "very obvious" starter drive behind the Pro. Nev

[RFguy]

yeah that is - the drive gear sprocket protruding for direct mate on the ring gear.

 

the lycoming starter I see has a slotted drive into the rear of the engine I guess the engagement stuff is inside the engine housing,

[facthunter]

Where if anything becomes dislodged it goes into the works and a shock loading into a train of small gears. Nev