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jlaird

jlaird

Great Pumpkin
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Very intresting, started right up of course.

And after two runs of a mile or so each I still have no oil leak at all, none.

However, second gear acts like I have no synchoniser. Shifts fine when engine is off but with engine on it is awful.

I know what the problem is now, about time, he replaced the 2ed gear synchoniser springs (3) with weeker springs. That was not a good move. Obvously I have to replace the old ones, I think the other changes worked fine and would have solved the prob.

Mike Miller says: "FWIW, The 1/2/R slide gear assembly has 3 ball/spring sets and 1 detent "Pill". There should not be 4 ball/spring sets. If you look at the inside of the 1/2/R slider, there is a "ramped" part of the gear that will line up with a through hole in the center gear hub, that goes on the mainshaft, when the outer ring is located to match the baulk ring "ears". That is where the "pill" goes. Put a little bearing grease in the hole and push the pill in."

Don't know about that pill never saw it maybe Alan did. Will ask in morning. Nor do I see it listed in the shop manual.

Mike also said: "Actually, for racing purposes, racers will stretch those springs to create a little extra grab when the outer ring moves forward to engage 2nd gear." So think that should have told us to leave em alone. Of course I have em but one more, #7, engine pull next week.

Mike, what does that mean??

Comment Mike please
 
Jack, take the car to the shop first with the engine in - then the mechanic can see hear and feel what you are talking about. will make his job much easier - then pull it again (wish I was there to help)
 
After thinking about this for some time and reading Mikes comments, I may, just may, understand.

If the springs in the second gear balls are too week they do not stop or engage the syncro if they are too tight they make it hard to shift. So they must be just right.

Oh Mike, the pill was not removed, the one you referenced in your comments.

I have learned to shift into second, let the engine go to idle and shift slowly.
 
Sorry guys. At the track the last weekend of April and then off to St. Louis mid-week for a electrical controls engineering conference. Then "Career Day" at the elementary school. 3rd graders just love the race car driving presentation. Or, maybe it is the stickers and patches they get for correctly answering the "Race-Car" math questions and being able to sit in an old race seat with belts, helmet and gloves on. Anyway.....

The detent springs/balls actually work with the shift rail detents to hold everything in place. The shifting into 2nd smoothly is a function of the amount of friction material left on the 2nd gear cone, the teeth condition (arrow-headed look)on both gears and the condition of the synchro. The synchro ring in the slide gear moves foward with the gear, and by the gear design, towards 2nd gear and engages the cone on the gear which has the friction material. The synchro ring actually grabs the gear to help syncrhonize the transmission internal "speed" with true "road speed" of the mainshaft. When the clutch is engaged (assuming upshifts), rpms drop and the gas pedal is needed to accelerate. The 1/2/R slide gear, which has moved forward to it's engaged position is held in place by the detents in the gear and on the shift rail. The shift rail detents are at the front of the trany case under the front of the side cover. 1/2nd gear is the upper shift rail closest to the side cover and the upper detent and spring

The "Pause" in the shift is helping to match the internal component speeds to negate the "crunching" sound/feel when the two gears mesh. Remember that 2nd and 3rd spin freely on the mainshaft, driven by the input/laygear. With the clutch depressed, the transmission internal speed is governed by the driveshaft speed from the rear axle and hence road speed. 4th is 1/1 via engagement directly to the back of the input gear. With the clutch depressed, it works similarly to the other gears. Engaging the clutch and depressing the accelerator speeds everything back up to whatever velocity is desired of the vehicle within the limits of the engine.

Note: The Brits called them "Baulk Rings". An appropriate name, since that is what they are doing. Baulking the rotating component speeds just enough to create a smooth shift.

Again, stretching or shortening the springs does affect the shift difficulty, but not the synchronizing regardless of gear. Racers also do what they can to shorten the shift throw. This also affects leverage and hence effort to make the shift.

HTH,
Mike Miller
 
Ok Mike, think I got it maybe. Miss Agatha is up on stands again ready for the 7th engine pull to put the orginial springs back in. Lighter weight springs I did not need.

My only adversion to all this is there does not seem to be a way to test the tranny before it is installed. If I don't get it right this time it will be the 8th pull. However, I will get it right.
 
Mike, here's what I want to know, did you ask those school kids the "coal" question :smile: :smile:

Jack, you're in good hands with my buddy Mike on tranny advice.
 
Hap: Nope, left all the "Power Generation" type questions to the two guys I recruited to present to the 4th and 5th graders. One did "Electricity" and the other did "First Robotics" and talked about the role engineering played in each. The kids were too interested in the race seat, helmets and other racing related things.

Jack: There are some inspections and bench checks you can do to determine condition of some of the components. Make sure the 2nd gear syncro ring can "grab" the friction cone of 2nd gear and basically stop it from turning when you have the mainshaft out. Hold the mainshaft by the tail in a vise. Do this before you change the springs. Also inspect the small "Dog" teeth on 2nd gear and the internal channels on 1/2/R slide gear. Both should be "pointy" like arrows and not worn back too much or flattened. There is too much to put into a single posting about all the nuances, but this guidance is general and applies to 2/3/4 since they are synchronized. 3/4 slide gear has syncros and engagement teeth on both ends. 3rd takes more of a beating than 4th.

HTH,
Mike
 
Thanks Mike. I am pleased to report that there is no wear on gears, syncros or anything else in this tranny. It had been in storage for many many years since comming from the factory. Needed cleaned well, and a few things corrected after the auto shop class opened it and put it back together mostly. Anyway, it is a fine unit as best we can tell. Oh yea first gear does not wine either.

Mike if I had known I would have seen that you got it to work on. Sorry bud. A friend of Haps and all that.
 
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