Reverse Gear selector jumps out of gearselector?

[ChristianBF]

Hello all, hello from Haderslev, Denmark, where we run an Atomic engine from 1979. In a sailboat bought and custom build by my great-granddad in 1935.

please see the two pictures in the post or the imgur link, this little “tap” for pulling the reverse gear lever jumps out of the hole again and again. We have tried to move the “gear selector” below, over to the right side, and fix it, but it does not help,
we have also tightened the revers nut but without luck, it continues to jump out. any advice out there?

kind regards Christian Fuglsang from denmark

https://imgur.com/a/oMjen99

PS i have noticed the pictures are being turned 90 deg counter clock wise by the forum. For correct orientation please use the Imgur link

[Al Schober]

The cross shaft for adjusting reverse has been modified. Usual install has a pin (swaged in place) that hold a roller. On yours I see a hex head. I suspect the adjustment was made too tight, the pin sheared, and the roller fell into the sump. Repair was not properly done.
I also suspect if you look at the piece the actuating cam bears against, you'll find it is heavily worn.

[Al Schober]

Here are a few more photos that may help.
First shows an assembled view with labels. With the adjusting nut removed, the adjusting rod can be slid to the right, allowing removal of the actuating bar.
The next photo shows the end of the adjusting rod with the roller in the slot. At this point, you can use your finger to feel if there is a groove worn into the side of the brace.
In the next photo the adjusting rod has been removed and you can see the cross pin in the adjusting rod. This pin is about 6mm diameter. The roller measures 12.4mm.

[ChristianBF]

Thanks, for Measurements.

The cross shaft for adjusting reverse has been modified. Usual install has a pin (swaged in place) that hold a roller. On yours I see a hex head. I suspect the adjustment was made too tight, the pin sheared, and the roller fell into the sump. Repair was not properly done.
I also suspect if you look at the piece the actuating cam bears against, you'll find it is heavily worn.

Your knowledge has led to great ideas, the 12.4mm is an interesting number which we could not find in the instruction manual, the bolt is an M7 (7mm), I will get our factory smith to make a new roller on the Lathe today. This will hopefully help, this is at least a start to a solution.

My dad has also noticed that the "brace" as you call it has a hole in it, is this for fastening the brace? because the brace has also become loose, the whole Clutch mechanism can then move freely up and down on the planetary gear assembly, which is very concerning.

but this is probably a problem connected to the missing roller sins everything is a bit more lose the intended.

I will write again regarding this when the new roller has been fitted.

Thanks again from Denmark.

[Al Schober]

Fitting a roller to the M7 bolt seems like a reasonable way to go.
The brace is meant to hold the planetary brake band in a fixed fore/aft position. The aft end of a brace has a large hole in it and goes around the shifter cross shaft. The fwd end of the brace has a smaller hole that fits over a pin in the brake band.
Removing the brace requires removing the transmission cover. Same for the cross shaft unless the cover is modified to provide a hole - photo shows mine with the hole.
I checked into Haderslev, and find I was quite near there about 20 months ago. We were visiting relatives - spent some time on Bornholm, a couple of days in Copenhagen, stop in Middelfart, up to Ry for two days, a visit to Ribe, and finally a visit to Flensburg (used to be Danish). Had a good time!

[ChristianBF]

Fitting a roller to the M7 bolt seems like a reasonable way to go.
The brace is meant to hold the planetary brake band in a fixed fore/aft position. The aft end of a brace has a large hole in it and goes around the shifter cross shaft. The fwd end of the brace has a smaller hole that fits over a pin in the brake band.
Removing the brace requires removing the transmission cover. Same for the cross shaft unless the cover is modified to provide a hole - photo shows mine with the hole.
I checked into Haderslev, and find I was quite near there about 20 months ago. We were visiting relatives - spent some time on Bornholm, a couple of days in Copenhagen, stop in Middelfart, up to Ry for two days, a visit to Ribe, and finally a visit to Flensburg (used to be Danish). Had a good time!

So we installed the new roller a couple of weeks ago, and until now it seems to have fixed the problem, but we will make a better-fitted roller in the winter as a more longterm fix.

again thanks for the help

[ChristianBF]

The long term repair has been made!

Hello again, after some time.
We have now done the long term repair has been hade. As you can see on the picture a new roller has been made, and a new bolt.

Special thanks to [QUOTE=Al Schober;122101] for helping us to get the right measurement on some of the components.

When covid is over and you are in Denmark feel free to contact us if you want to know anything.
christian@fuglsang.dk

Best regards.
The whole Fuglsang Family.

[Al Schober]

Glad your reversing gear is working again, and glad to have been of assistance. That's what this forum is about - people helping each other.

[sastanley]

Al, I don't know how I missed your detailed and labeled pictures earlier in this thread from 2020, but a couple minutes studying it clears up (for me anyway) some of the mysteries of the reversing gear.

Learn something new every day!

Thanks again!

Also, thanks to Christian for following up. A few years from now, someone will see your fix and have a path to repair!!

[Funky cat]

Reverse adjusting nut.

Hello everyone, this is my first post on this forum. What a great place for info on the a4s. I've learned alot about these great little engines. I do have a problem with the adjusting nut for the reverse bands. Very simple procedure, turn nut clockwise to tighten bands right? Well I've put enough torque to on that nut that I've broken the reverse shifting bar. That said I machined up another one put it back in and tried turn the nut counter clockwise, ended up bending the new bar. Does anyone know why t would take so much force to turn this nut? I've used penetrating oil and have also used a little heat, but no luck turning nut what's up? I really. Don't want to break anything else.

[Al Schober]

Wish you'd contacted us sooner. Also wish you'd started a new thread.
Do you have the Moyer Manual? If not, get a copy.
I suspect you lost the roller from the end of the reverse cross shaft opposite the nut. See the previous photos in this thread. The nut is supposed to turn easily and actually has a spring clip to keep it from turning on its own.
The shifting bar you refer to has a taper to it. When the shift cone in the transmission moves forward, the shifting bar moves aft and the taper rides against the roller and tightens the band. No roller? The reverse band doesn't get tight and you have no reverse.
Look in the slot in the end of the reverse cross shaft. Should be a roller about 12.4mm in diameter. If it's not there, we've found the problem and can address a solution.

[Funky cat]

Reverse shifting nut

Al, thanks for your reply, all the parts ,roller, retaining spring and pins are in place, I just can not get the adjusting nut to turn. It's. As if it's frozen tight. It will not turn in ether clockwise or counter clockwise, that's why I broke the the tapered reverse bar buy putting obviously to much pressure on the shaft. I understand the engineering completely. Just don't understand the tightness of the adjusting nut. Any thoughts would be appreciated . The engine is in a Catalina 30. Little room to move because of gally.