Need Help With Belcrank Linkage For Cal 30 Shift Lever

[captainmurph]

At the end of last year, I adjusted my forward gear due to slippage. Apparently I went one too many notches and it wouldn't come out of gear. After getting it into the slings, I made a mental note to adjust this spring before launching.

I spent the best part of the afternoon chasing that adjustment and the actual mechanical linkage that controls shifting: I definitely need some help!

Here's the questions:

1. The shift lever attaches on the left side of the transmission and there are multiple possibilities.
2. One is for the set screw to be forward and use the forward position of the lever.
3. Another is set screw forward and lever nearly vertical.
4. It can also be installed with the set screw aft and lever near vertical.
5. Or, the lever can be clocked backward as well with the set screw aft.
6. In addition, there are two holes that the clevis can attach to.
7. Which lever position and hole position is used on your boat with the belcrank (long curved rod with clevis at each end) type of linkage.

As you might know, this type of linkage is like the bellcrank linkage on an older airplane that controls (mechanically) positioning of a control. There is a bolted attachment on the port side of the forward cockpit with a lever which is (based on the way it was installed) lifted to engage forward, clicked down to neutral and held down with your toe to use reverse.

Anyone with similar linkage help me on this? I'd sure like to splash on Tuesday, but have to get this rigged right first. I'm thinking that I will really loosen the forward gear adjustment more as well, but really could use info on comparison with how your system is rigged.

Thanks a bunch in advance!

Murph

[Mo]

Hi Greg,
Can you get us a couple of pics...you can use a cell phone or digital camera and upload them. Pics from a cell phone generally don't require resizing.

[Al Schober]

Greg,
Not many A4s have the bellcrank linkage. Personally, I like it as it eliminates the friction in the cable. Just wish I had spots for the bellcranks.
The torque on the transmission shaft to get it into/out of gear is a fixed value - and the longer the lever arm, the less the forces in the linkage. However, at some point you're going to run out of room for linkage.
The position of the arm on the transmission should be such as to give a right angle to the next pivot in your string of bellcranks (not sure how many you have). Also, all the bellcranks and arms should be about the same length. The shaft on the transmission will rotate a certain amount from neutral. Keeping the bellcranks the same length will keep everything rotating the same amount.
FWIW, my last reversing gear job I changed out to a new stainless shaft from our host. A thing of beauty! Should be on the 'must change' list for any job opening the gear!