20 min trani gear change

[mwizard]

Can't find the thread where I think Barry mentioned someone who could do 20 min gear changes. Well, I changed mine today, 3rd up 3 mph to 73 and 4 up 8 to 88 after getting soundly beaten last wkend at AAS at Crows Landing, and I am pretty sure that 1 hr would be a very fast time. It took us 2 hr
Mark

[chrisw52]

I can see someone doing a gear change inside of 20 minutes. It's not too hard if your careful about assembly and disassembly. I put up an article on my blog about changing gear sets on a LD200 transmissions.

gearset change on a LD200

[mwizard]

Yes, without a dummy shaft you will be in trouble. Even with one, it was not easy.
Mark

[Brian]

The reason it takes me a long time to do a gear change is how long it takes to clean the old goo off the flanges, mostly. Plus having to root around for a new tube of goo when the old one is all dried up. Finding the baggie with the new cotter pins usually takes 20 minutes all by itself. Plus going to the parts store to buy a can of gear fluid when you discover you used the last one and forgot to buy more. Not to mention at least 10 minutes trying to get the last half inch to close up (Mk9 anyway). Has anyone ever figured out exactly what is hanging up to make that last half inch so hard (and sometimes so easy, I've actually had the gearbox just slip right on first try).

Brian

[rickb99]

20 minutes is somebody who has done a LOT of gear changes and does it at least twice a week to keep the skill level up.

Keith Averill taught me to never use sticky GOO on the flange seals. Stay with the good old Hylomar and life will be easier.

Never had a dummy shaft but it would have been nice. Just need a soft left hand and nimble fingers

A 'normal' time for MK9 gear change should be about 50 minutes to an hour.

[EACIII]

Get an LD200 and forgot all about goo. (O-rings) That alone will save you 10 minutes on your gear changes. I figure 45 minutes for an average change, not rushing.


Ed

[kea]

I bet Tim Gaffney I could change the gears on his Reynard FC in 20 min. I got side tracked showing his kids what I was doing and lost by a few minutes.
But then again, I did my first Hewland ( no wings) Mk series gear change in 1971. I know without looking every tool and step. I think 30 minutes is a reasonable time if you don't have long diffusers and wings to deal with. Better so on an LD that doesn't need sealant.

[rickb99]

..... I think 30 minutes is a reasonable time if you don't have long diffusers and wings to deal with......

Hey Keith, Which FC's don't have wings??


KIDDING

Okay, I'll give you 30 minutes as long as the person is doing it a least 2 or 3 time a month and everything goes smoothly. But, one hiccup and you can add 15 to 20 minutes.

Have to admit in our case the biggest 'problem' was the last 1/2 inch... LOL I never did ask you what the trick was to avoid that problem. Jeff got so frustrated at that during one change he almost threw the entire gear assembly across the garage. Luckily, my screaming stopped him. I think on that day we alternated trying it and finally on the 7th or 8th try, it went.

[Hawke]

20 minutes is certainly possible. Couple of tricks I use:

1. 3/8" butterfly cheap rattle gun,
2. Get all the other tools laid out in order, along with new split pins,
3. Put the gears you are changing on the bench,
4. Only use Hylomar on the sealing surfaces. You can reuse that stuff many times.
5. Use an old plastic freezer ice block tray to hold all the nuts and washers in groups,
6. Use a stand to hold the bearing carrier upright,
7. Disassemble and layout the gear stack in order, keeping upper and lower shafts in order,
8. Put the drained oil on top of your tool box to remind you to put oil back into the box. (may not be applicable to young people - who can remember everything. More mature gents will understand)
9. Install using a dummy shaft, and the big time saver:
10. Just when you get to the last 1/2" and no huffing and puffing will do it, rotate the lower shaft while just pushing gently on the bearing carrier. It will always just drop in, much to the amusement of those watching on. Some will look like you have just discovered fire.
11. Unlock the 4th and reverse forks, as soon as you tighten the big nuts. Nothing is more annoying than having to remove the rear cover after assembly and find you have forgotten to.

[stonebridge20]

I did a hot off the track MK9 about 15 years ago in about 17 minutes. Clean and apply new sealer,.......Um,..... no!

[Tom Sabo]

alternative last half inch tricks:
1: if car is jacked up, turn a rear wheel while pushing gently on rear cover
2: if car is on ground, push starter button while pushing gently on cover -- i use this method in conjunction with a bungee cord to apply pressure.

[kea]

Have to admit in our case the biggest 'problem' was the last 1/2 inch... LOL I never did ask you what the trick was to avoid that problem. Jeff got so frustrated at that during one change he almost threw the entire gear assembly across the garage. Luckily, my screaming stopped him. I think on that day we alternated trying it and finally on the 7th or 8th try, it went.

The "trick" is, I do it while the car is on the ground so I can roll it forward and backward. I leave the forks in the same position I did to loosen the pinion and layshaft nuts. The movement of the pinion shaft makes it easier for the gear hubs to line up with it's splines.

[Frank C]

There is another way to save a little time. Wendell Miller was watching me do a change in the paddock one time and noted that on the MK 9, pro mechanics just don't use the two "buried" nuts which require a wrench rather than a socket.
- Frank C

[marshall9]

The "trick" is, I do it while the car is on the ground so I can roll it forward and backward. I leave the forks in the same position I did to loosen the pinion and layshaft nuts. The movement of the pinion shaft makes it easier for the gear hubs to line up with it's splines.

Sandbagger ! Keith is holding back secrets. He can talk you through it in less than 20 minutes

[R. Pare]

Was at Brier in the early 80's when a fellow FF competitor's 13 year old son changed a ratio while on the false grid in less than 10 minutes ( Bernstein, I think - drove a Crossle).

[Jim Garry]

Mark don 't feel bad. The first few times I did it, it took about the time you just needed. After awhile I got it down to under 45 minutes consistently. At an event we once did it in about 1/2 hour but we didn't clean the flange.

Do you have a stand to put the gears into so they stand up? This helps immensely. You can easily make your own. And have a box of all the stuff you'll need.

BTW, did you use a good cotter pin or a hardware store version? I once used a cheapo pin and it broke during use.

[Fred Michael]

If your cotter pin broke you did something wrong.

[Jim Garry]

Thanks Fred. Does that mean it's ok to use crappy cotter pins?

[Fred Michael]

There should be no pressure on the cotter pin. If there is then the quality of the pin is not going to matter.

[mwizard]

[QUOTE=Jim Garry;439639]Mark don 't feel bad. The first few times I did it, it took about the time you just needed. After awhile I got it down to under 45 minutes consistently. At an event we once did it in about 1/2 hour but we didn't clean the flange.

Do you have a stand to put the gears into so they stand up? This helps immensely. You can easily make your own. And have a box of all the stuff you'll need.

I hope this new set up is my last gear change. We will see tomorrow. Ok, maybe I will get to road racing someday
Mark

[WRD]

10-15 is where it's at, hats off to the dummy grid kid, I once did a Ralt Atlantic in 10 minutes jiggling the right rear tyre with my foot to move the pinion shaft a little.

My big nail biter was the Imola GP in 2000, we had a major gearbox issue that reared it's head in morning practice, the box was destroyed and 40 minutes before the race the gearbox was on the bench in the back of the garage. With about 25 minutes left before pit lane closed for the lap to grid we had no idea what to do, we grabbed a 5 gallon bucket of Barrierta grease and literally dipped every hub set, ratios, forks, everything into it before we loaded them. We popped on the front cover with around 20 minutes to spare and wheeled the fully assembled rear end into the front of the garage. Everyone got onboard, box went on, floor tray went on, quick drop onto the scale pads, engine cover on and Villeneuve went to grid with about 30 seconds to spare. We finished 5th and many beers were consumed that night in the airport!!!!