VCCA Home Forums TECHNICAL - GENERAL Mechanical - Engine, Trans, etc Shifting Issues in 31 Coach

Well I am moving on to the clutch/gear area fellas -----Ever since I got the car there has been an issue with shifting.
Lots of grinding if you are not really careful.Forget downshifting unless you double clutch,wait,try to match up engine speed with gear speed,etc. And I am aware it is non syncro so no chance of downshifting into 1st gear until fully stopped. It gets much worse if you fill the gearbox to proper level. It seems the less gear lube in gearbox the smoother it shifts both up and downshifting. Would this be a throwout bearing issue or clutch plate issue ?? I am again in virgin territory here guys !! Thanks to all.Jay

I was not shifting soon enough and experienced the same thing. I get it rolling in 1st then quickly to second, and soon thereafter into third. I do double clutch up and down but may not need to going up.

What gear oil do you have in the transmission?

Dave

Hi Dave,there is 600W in trans and the rear. So,if I understand you,you were shifting to slowly and it was better if you shifted quicker?? Interesting,maybe if I would shift faster,everything is kinda spinning at same speed and would mesh better?

I plan on draining both trans and rear today as they have both been sitting for 3+ years so oil is probably all gummy sludge by now.Should I thoroughly flush these areas with a cleaning solvent,like Seafoam or similar crud dissolver before I refill them?? After seeing the 1 1/4" of thick filthy sludge in oil pan I can only imagine they would be in similar condition?

You should check your owner’s manual. I expect that it recommends you drain and flush the transmission every 2000 miles or something like that.

Normally a “light” oil is used to flush the gearbox. My suggestion is to drain it and fill it with regular 10w-30 or 10w-40.
Drive the car for a few miles under light loading conditions to circulate the oil and get it warm so it flows everywhere.

Drain it and refill with 600w.

I have seen posts where people flush with kerosene. I agree that is a good solvent but I doubt if I would drive the car with that in it. I also expect that any automatic transmission fluid would work as a good flush oil.

I am sorry I wasn't clear. I get the car just moving , maybe 5mph and shift to 2nd, and then at about 10 go to third. Each car is probably different but with the rear end gearing don't have a problem except the tall hills.

I was trying to shift it by letting it wind up like a modern car.

Dave

No Dave,you were clear,I just read your post wrong!! After I got to garage and thought about what you had said,that little light came on in my old brain and I said "Oh,I know what he means now !!" Thank you ! I was also doing as you described,kind of driving like it was a 1960 instead of 1931 and going a bit to fast in 1st and 2nd !! You are correct in the "shift sooner" approach.

The gear oil is not the problem....
You have to learn how to shift a non-syncronized transmission.
Shifts need to be mad slowly with a constant slight pressure on the lever so when all gears get spinning at the same speed the change can be made with a little more pressure on the lever. You have to aquire a feel.
600 gear oil when cold will place drag on the gears and when it thins out after several miles it will change the shift process.
Double clutching is necessary for faster shifting usually.

Thank you Chev Nut. I do have quite a bit of experience driving vehicles with non-sync trannies and I normally do not have any real problems. That being said,this beast seems to act somewhat differently than others I have driven.
It still baffles me as to why,when I fill the gear box to spec level with 600W oil as called for it is much more difficult to shift than if the gear box only has about 1/2 of oil called for in owners manual. My mind tells me if I fill to specs,that is where shifting would be the smoothest and easiest---but that is not the case in the 13 years I have been driving this little buggy. I can't help but feeling it is wrong to run with it half empty,but,that is where it works best.Confused so I am ....

If it fills the same way my 1929 & 1930 does ? and my friends 1931. You remove the fill port on the side, then then fill just up to the threads ?

I know if you over fill the fluid can seep in the u-joint then to the torque tube, rear, end, shaft ends, brakes :(

also remember they are are STRAIGHT CUT gears , making it more fun to shift, acquired feel and skill. that is why they call them a crash box, because you end up crashing the gears into each other.

I just a complete rebuild on my 1929 transmission, so tons of picts coming apart and going back together.

first photo shows hte fill port, bottom square head plug.
second shows transmission filled to threads of fill port, top of transmission off this is 600WT oil, you can see the fill port bottom right area

Hey BearsFan315,It has been a few years but,yes,I do believe thats me too!! I only had time today to remove the inspection cover on the differential and clean that out. It was amazingly clean,no debris,barely any sludge and oil was clear,not cloudy or any signs of moisture in it ! All gears looked in great shape as well. Happy me ! Ordered new gasket from FS already so it should be here Friday. It is cork and some kind of plastic as I read ----should I use Permatex or not?Last person to do this smeared that stuff on everything !! Not a fan if not necessary....Thanks again. Jay

My 31’ with the 600w will grind a little at first when cold but once it warms up, it shifts just fine. One thing I found that helped with the shifting and double clutching was too adjust my clutch pedal. It was grabbing too high with just a little free play and my double clutching the pedal wasn’t getting the proper results . After I adjusted the free play and have the clutch grab with the pedal lower, I shift as smooth as Mario Andretti in a square box Ferrari.

Thanks Chistech,I will see just where it grabs after I get all fluids changed. Also,I have no idea what condition the clutch plates are in or the throw out bearing either. What indicators should I be looking for to know if bearing needs replacement? Is there a way to inspect the clutch plates and throwout ?? I have never noticed any clutch slippage.
Thanks again for everyones help. Jay