Saw fires & yanks starter handle out of my hand. Why?

[67L36Driver]

Plug fires when the points open. Therefore widening the gap advances the timing.

Most points are set at .015". I have an 032 on the bench that runs a touch better set at a tight .020".

I have several nasty 'biters'. Mostly the problem of a lean fuel mix when cold. I leave the ignition off, set the choke and pull it over two or three times. Set the choke at 1/2, flip the switch and pull like you mean it.

Less danger of hyper extended fingers.

 

[strtspdlx]

Plug fires when the points open. Therefore widening the gap advances the timing.

Most points are set at .015". I have an 032 on the bench that runs a touch better set at a tight .020".

I have several nasty 'biters'. Mostly the problem of a lean fuel mix when cold. I leave the ignition off, set the choke and pull it over two or three times. Set the choke at 1/2, flip the switch and pull like you mean it.

Less danger of hyper extended fingers.

Not to argue but if you open the gap wouldn't it take longer for it to shut and recharge the system before opening and allowing the primary circuit in the coil to discharge? Wouldn't that retard timing. As in takes longer for spark to occur.


Regards-Carlo

 

[fossil]

Not to argue but if you open the gap wouldn't it take longer for it to shut and recharge the system before opening and allowing the primary circuit in the coil to discharge? Wouldn't that retard timing. As in takes longer for spark to occur.


Regards-Carlo

Nope

 

[president]

An old 041 would load up with bar oil from a leaky 0 ring straight into the
cylinder .It puked oil
through the plug I know this is a red hearring to whats really going
on
but my irrelavent 2 cents should at least get some dislikes!

 

[buzz sawyer]

I think we're missing the point. The starter is designed to release once the engine is running forward faster than you can turn it with the starter. However, when it fires before TDC and tries to run backwards as you are pulling the rope, the starter is still engaged and pulls back on the rope. It can't over run the pawls because it's trying to run backwards.

You see this almost every time you shut the engine off with over running pawl type starters. The engine tries to run backwards for a second and snaps any slack out of the rope. There have been several threads questioning the practice of pulling the starter rope out a few inches before shutting the saw off to prevent the brief reverse pull on the starter. Some manufacturers actually encourage this. I don't believe you would see this with fairbanks/morse type starters because the rope must be pulled for the starter fingers to be pulled out far enough to engage the cup.

 

[67L36Driver]

Nope

Up to a point. You can't go crazy wide because of the magnetic field thing but it works. That is, silly wide will have a weak spark.

 

[Mastermind]

I have had the tendons in my wrist torn. Some saws will bite.

 

[GPX433Todd]

My YAMAHA Grizzly 660 has a pull start back-up option on it. Feels like the Titanic is attached to the other end of the rope. When it decides to pull back on you, get ready to lose some fingers. Plain dumb engineering on their part.

 

[fossil]

Nice to have when the battery goes dead. I have one on the 500 Cat. Suzuki engine. At least you can sit on the sucker and it doesn't flip over when it hangs up.

 

[strtspdlx]

Yeah my Suzuki quad runner 250 sucks to pull start. It has a decompression lever but I couldn't never get it started trying to pull it.


Regards-Carlo

 

[Thomas Venditto]

Yep, I get that. There is a lot more surface area to accumulate that 150 pounds per square inch on with a saw of this size.

It's completely beyond me what would causes this specific situation though. My simple mind can't wrap around how the starter cord could be forcefully retracted back onto the spool. Given how starters work it seems like the only way for the flywheel (not the recoil spring) to pull the cord back it would have to be turning backwards.

To be clear, it's not that I'm hitting the high compression and the handle is just pulling out of my hand and coiling back up from the forces of the spring. It is literally snapping - with great force and speed - the handle back in. Absolutely not by means of the recoil spring. It was yanking the thing back with such force that I was genuinely worried it was going to break off a fan cover fin.

The saw is firing early and running backwards.