Topic: Will not shift to 3 - really resolved :)

[scottly]

So the neutral switch is not fully seated?

[atm cycles]

I'd be careful if I were you. If light is on all the time then switch isn't in all the way with double o rings. As you probably know the switch is a key holding the shift drum from moving laterally. If I were to guess I'd say your switch wasn't in all the way to begin with. That's the same thing that happened to a k6 I had. Spit those cases twice before noticing !!!!!

[flybox1]

Glad you got it working.   I bet the double ring is preventing.the ball from being depressed in all gears as it's not touching the shift drum.

[Bailgang]

So the neutral switch is not fully seated?

This all does sound kind of strange because if the neutral light was operating correctly at first but not shifting into 3rd but doubling up the 0-rings and it does shift into 3rd now but neutral light stays on all the time that just tells me that if the switch wasn't seated properly the first time with one o-ring then it definitely isn't seated properly with 2 o-rings now either.

[PeWe]

The root cause was the neutral switch?

[70CB750]

The neutral switch is actually seated all the way, there is no crack left between the switch and the case.

I never sealed the side cover, with all the on and off, there was no reason.  Next thing is to open it up again and check the drum for play.

I will also find a different switch and try it with it.

Don't get me wrong, it is a breakthrough in diagnosis, not a solution.

[flybox1]

If you go back to just ONE N switch o-ring, does the shifting issue come back?
Way strange if it does, as I dont see how the switch itself could prevent shifting/drum rotation.
oh well....its working 

[70CB750]

If you go back to just ONE N switch o-ring, does the shifting issue come back?
Way strange if it does, as I dont see how the switch itself could prevent shifting/drum rotation.
oh well....its working 

Just the guy

Would you know how far the switch reaches in the drum? I never had it apart. My guess is the narrow part of the switch rides in the groove???

[flybox1]

Yes, in the groove, and atm cycles is correct.  The N switch holds the drum in place.
Based on wear patterns on the two drums i have, there is minimal contact of the end of the switch against the drum.  Just the ball rides on the drum, and falls into place @ neutral.

Shift it into neutral and then stick your little finger up in there to feel the detente.  Dont worry, she wont bite 

[70CB750]

Thanks!

There could be some gunk floating too, pulling the engine is always an option, but the last one 

[scottly]

The switch when fully seated engages the drum about .125" deep. Notice the witness marks below the ball in the attached pic.
When fully seated, there is about .008" lateral play in the drum, but with the switch removed the drum has about .125" lateral play, with outward movement limited by the shifter mechanism; perhaps this is how the thin plate on the end of the drum got bent?
The groove for the o-ring is only .140" deep, and a stock o-ring is about .130" thick, so I doubt the switch is fully seated, especially if the light is always on.
Remove the o-ring(s) and see how the switch fits into place; you should be able to press the switch in with your fingers with the drum aligned laterally. If the drum isn't in the neutral position, you can feel the ball depress the spring before the switch bottoms out solidly against the case.

[atm cycles]

Somewhere on here there's a thread about installing the neutral switch. I can't remember what what was best in regard to the o ring. Had to do with putting the o ring on the switch first then installing vs putting o ring in case then install switch

[70CB750]

Thank you, Scottly, that helps.

CMSNL lists the o-ring as 18x3 [mm].

The o-ring I used since the original one was old, is actually 3.3mm.

[70CB750]

My switch had almost zero witness marks, I took it to the lathe and polished it up, but nothing showed when I pulled it out again.

[scottly]

Prokop, the witness marks only show up after use...
ATM, the o-ring must go into the case first.

[70CB750]

I pulled the neutral switch, installed only on o-ring, the first 3.3mm and she shifts perfectly.

Engineer's nightmare - it works, but you don't know why.

Anyway, happy, happy. She has a nice sound and feels very solid, I am learning to use turn signals and second gear - Dorothy has no signals and the 2nd is worn out for quite few years now.

[atm cycles]

Happy to hear it. Little doubt in my mind that switch initially wasn't seated properly. Glad you got it before you bent a shaft and broke gears

[flybox1]

Nice.   Notice any drips without the oring there?

[70CB750]

Nice.   Notice any drips without the oring there?

I never run her without o-ring, just tried different sizes and two o-rings together.

She actually sealed well with the cover just bolted on, yesterday I closed her for good with some permatex.

[70CB750]

The shifting issue kept coming back like bad penny.  Sometimes it would shift all the way to 5 and would not let me get down again.

Sometimes it would let me ride between 2 and 3 or 3 and 4.

I took the complete linkage out of the K0 and the neutral switch and swaped it out - it made no difference.

But the K0 shift drum is much easier moving, much looser, you touch it and it spins, unlike the F3 engine.

Yesterday I took the engine out, flipped it over and opened it up.  There does not seem to be anything out of ordinary, forks look almost new, the drum is solid with no burrs, no chipped gears, nothing.

I was able to reproduce the issue with the case open - at least it feels the same.  It is when the dogs are not lined up and you slide a gear over and dogs do not end up in a hole.  Does it make sense? Like the gears had a problem turning against each other to log dogs together.

I used 15W40 diesel oil to brake her in, I am sure that different oil would not fix it, but what do I know?

Anybody cares to comment?

[flybox1]

strange it would not let you down out of 5th either.
yes, i can picture what you are describing....the dogs of the gears are hitting each other instead of falling in between and meshing.
The only thing i can suggest is taking them off the shaft one by one, checking bushings and circlips and thrust washers for proper orientation.
I have a really good trans supplement another forum member sent me.  You might already have it.  PM me your email, and ill send it.
Here is the first page...

[NobleHops]

Straying out of my depth perhaps, but check the condition of the bearings on the gear shafts. In my 400 one was cracked and sitting up on the pin that locates it, and the binding it intruduced made shifting hard. An extreme case that was obvious to see and repair in my case, but perhaps a worn trans bearing is causing something to bind sometimes in your trans.

P.S. How much side to side play do you find on the shift drum?

[MoMo]

Do you know if the motor was ever apart?

[70CB750]

NH:  I will check the side to side play for sure

MoMo:  It does not seem to, no wrench marks on bolts and such.

[MoMo]

NH:  I will check the side to side play for sure

MoMo:  It does not seem to, no wrench marks on bolts and such.

reason I asked is that I thought someone may have put either a circlip or thrust washer on backwards.