no syncro 2nd advice

[daver80]

66 MGB- I've been driving her a long time and have never been able to downshift 3rd into second without grinding. Kinda takes some of the sports out of sports car. Not ready to tear everything open, (time and money) any advice on double clutching- is that what it's called? I suspect that the 2nd gear syncro is shot. I just use my brakes a lot going into turns. Dave

 

[Mickey Richaud]

Hi, Dave -

If double-clutching is your only option, you'll need some practice. When shifting, put it in neutral, let out the clutch, blip the throttle to bring rpm up to match where it was before shifting, then engage the clutch and go to the next gear. A little trickier when downshifting; you may have to do some experimenting with rpm.

With practice, you'll be able to amaze your friends, and it does sound kinda cool! :cooler:

Mickey

 

[WA1KWA]

Mikey's right, you have to match the revs to the gear you are going into, that's the trick. Again, like Mickey says, it takes practice. Get good at it, like my father, and you don't need the clutch to shift.

My father was amazing, he only used a clutch to get the car started, just matched the revs & never needed the clutch after that.

Colin

 

[Mickey Richaud]

And you can pretend you're Steve McQueen in "Bullitt"! That Mustang sure sounded pretty running through the gears!

 

[Deleted member 3577]

Now is a good time to master the art...

Before the rebuild.

BTW...
Buy another tranny from the yard and have a go at rebuilding it yourself.
Don't take a functioning transmission out or your down time will be much longer.

You should be able to pick one up for < $100
(Then you'll eventually have a spare when you do the swap :thumbsup: )

 

[1965_MGB]

I did what was said above. I was driving the car around without a first or reverse. I picked up another crash box at my local yard, had it rebuilt, and that made for a much quicker turn around time.

I know the non-OD transmissions for your car will go cheap. If you don't have any yards around that have MG's (not really a surprise), give Tony (Autoist) a shout.

 

[DrEntropy]

The "art" of double-clutch downshift can take some trial-and-error. Having another gearbox on stand-by is a good plan. The '66 has the "crashbox" first/reverse arrangement.

Mastering heel-and-toe double-clutch downshift technique can forestall the transmission replacement but if it has lost the second gear balk ring the layshaft (and bearings) will be the next thing to go.

My suggestion would be to acquire another box, rebuild it and swap units. I keep a spare on-hand ready for the task. The second-gear balk ring should be a "sintered iron" one, less susceptible to wear. They'll go 80K miles without problems if treated with respect.

 

[Deleted member 3577]

The second-gear balk ring should be a "sintered iron" one,

I think they 'sneck' quicker also...
(That could well be me justifying the enormous cost disparity)

I don't know how the B pedal box is set up...
Double declutching is made a lot easier by the addition of a throttle pedal extension on the A...

If necessary, I would highly recommend the 'Patty Hopkirk' modification on your car.
(Otherwise it's like playing twister

)

 

[daver80]

Thanks for all of the advice. As I stated earlier- I dont have the time or money right now to do a rebuild, or to pick one up for 100$. I dont have $100. What is the correct double clutching tecnique? I suppose that is the question. Dave

 

[DrEntropy]

As WTN suggests, a Paddy pedal extension is a really good thing.

To learn this ballet I'd suggest an instructor. Especially since the box in question is already compromised.

The order of business is (some folks may use different parts of their footsies):

1) ball of right foot on the brake pedal.
2) roll the heel of that foot to the gas pedal.
3) depress clutch, put box in neutral.
4) release clutch, while you modulate brake and rev engine to an RPM matching where it will be spinning if second were engaged at the speed you're traveling.
5) depress clutch, engage second.
6) release clutch while maintaining braking and engine RPM.

It takes an eyeblink to do it correctly.


You DO know NOT to engage first or reverse with that box unless the car is ABSOLUTELY dead-stopped as well? Failure to abide by this "rule" will strip the layshaft and/or cogs in short order.

Paddy extension in this shot is all I have on-hand:

 

[daver80]

Doctor- thats the process I needed. Guess it just takes practice learn that magic engine speed tranny speed match. Hey, by the way- maybe I mentioned it months ago, I had an 84 300D also, sold for a minivan about 6 years ago. 229k on her... Dave

 

[DrEntropy]

meh... Diesela has well over "a quarter" on her now. Still strong as an ox. :laugh:

 

[Deleted member 3577]

I found a bunch of U-Tube videos on the subject...

Here is one...

https://www.youtube.com/watch?v=W7bb2OKFKgc&NR=1

 

[glemon]

I had a TR4 with very bad 2nd gear synchros, I never learned to double cluth, but learned that if I shifted out of 1st at about 3000 and let it drop to 2K as I shifted to 2nd all was good, downshifting is trickeier as you may have to give it a little gas ot match.

I agree a rebuild is needed at some time, but it is kind of fun to learn to match the revs, also to have a very light touch on the gearshift, when revs match it will slide in easy.

My 3rd gear on my B is worn, I hardly notice anymore unless I am driving really hard.