Starter question

[Dave Bjornson]

I have a strange starting issue with my 8N. It's been converted to 12 volts, and has started fine until the cold weather hit. Here's the deal.
When I turn it over the starter spins fine until the motor starts to fire. At that point the (bendix/pinion?) retracts to the resting position and spins. In warm weather that was enough to start it. I don't have a VOM at home tonight to check the voltage at the starter under load. Is it possible that the voltage is dropping enough to prevent the bendix from extending during startup? Is this normal? It seems that if I could turn the motor over a couple more revs, It would start right up.

 

[Anonymous-0]

you need a new starter drive

 

[Dell (WA)]

Dave......Ron is correct, you need a new starter drive. Recommend the improved "clutch" type starter as it don't kick-out quite so fast ......Dell

 

[Dave Bjornson]

Thanks guys. One more dumb question. My carb has a 3/16" round hole in the side of the body on the opposite side from the main jet screw. (the side towards the seat).
It sucks some serious air during startup. Giant vaccum leak. Seems like it would suck a bunch of dirt in too in a dusty environment. Is it supposed to be plugged?

 

[Dunk]

(quoted from post at 01:07:16 01/08/10) Thanks guys. One more dumb question. My carb has a 3/16" round hole in the side of the body on the opposite side from the main jet screw. (the side towards the seat).
It sucks some serious air during startup. Giant vaccum leak. Seems like it would suck a bunch of dirt in too in a dusty environment. Is it supposed to be plugged?

Huh?!?!

 

[Dell (WA)]

Dave......thats supposed to be the "sinstered bronze" filter drain hole at the mouth of yer carb throat. They drop-out or dissolve in carb cleaner. Ford p/n: 8N-9694 or John Deere p/n: 95-78. And YES, you need one to prevent sucking dirt into yer carb. Surprizingly enuff, it missing don't screw-up yer air fuel ratio. But it can't supply enuff air to run yer engine like yer oilbath airfilter can. ......Dell

 

[DollarBill]

[color=darkred:4d9858ae2d]My carb has a 3/16" round hole in the side of the body on the opposite side from the main jet screw. (the side towards the seat).[/color:4d9858ae2d]

Is this the hole you're speaking of?

If so, the photo shows the bronze filter Dell was telling you about.

 

[Dean]

You have found your starting problem, Dave.

Allowing "serious air" into the air horn while cranking is the same as trying to crank without first closing the choke fully.

Dean

 

[Ramon]

As provided before, the new heavy duty drive is the answer. However, if it is not now so equipped he may need to grind out the transmission housing opening into the oval in order for it to be installed. I always used an air die grinder to perform the job.

FWIW, Ford actually sent the dealers a printed template for this as a guide when they first started selling the larger diameter drive....

 

[Dave Bjornson]

Nope, This is a 3/16" (approx) hole in the upper body Where the red arrow points.
Huge vacuum leak! Thanks in advance for all the help on this forum you guys are great!

 

[DollarBill]

That is an access hole the manufacturer drilled to access passages in the throat of the carburetor.

As you probably know it should be capped - I think it was originally sealed off with a brass expansion plug. Might be hard to find the exact replacement - I'd likely try some type of epoxy making sure not to plug up anything except the access hole.

 

[Dell (WA)]

Dave.......us guessers are only as good as what the guessee can describe. I flunked mind reading, just ask my ex-wife of 32yrs. That little hole definitely needs sealing or it will upset yer carb mixture (lean).

You might find a plumbers stopper sink ball-chain (they come in different round-ball sizes) that you can snap a hollow ball off'n that you can then "set" (expand) in the carb hole. Failing that, J&B epoxy weld could work for you as long as it don't go too deep into the carb and plug the wrong holes. .......Dell

 

[Dave Bjornson]

Thanks guys! I'll plug er up.
While I've got your attention, Can someone explain the physics of what causes the pinion gear to retract when operating normally?
Is it the increase in engine speed caused by cylinders firing?, or could a dummy keep holding the switch down and actually ruin it from over-revving?

 

[Dell (WA)]

Dave.......starter drive, sometimes called "Bendix" drive, has this spiral wrap that screws up the starter shaft when the starter motor starts turning. As it screws, the starter gear engages the flywheel ring gear and turns the engine over. When the engine starts (or coughs) the faster turning engine UNSCREWS the Bendix back down the shaft and the starter gear goes with it. The starter motor is now "free-wheeling" and whines away. And the driver then "disengages" what ever started the starter. (key or button) Simple, eh?

And NO, holding down the starter switch won't "ruin" the starter motor, altho you might gitt itt HOT and throw some solder, but this takes time to do. .......Dell

 

[Dave Bjornson]

Thanks. So how would a new starter differ in performance than what I have now? in other words, why would a new starter stay engaged longer?
Just want to understand b4 I plunk down the cheese....

 

[Dell (WA)]

Dave.......you don't, you replace JUST the starter BENDIX, not the entire starter motor. Understand??? We recommend the improved "CLUTCH" style starter drive $50 (cheap) .......Dell

 

[Dave Bjornson]

Gotcha! Thanks a million