Lister 2G Gearbox

[Chris Pink]

 

The 2 threaded adjusters with locknuts in the picture, two used in forward (toggle lever screw) , one used in reverse (brake band lever adjusting screw)

 

What is the procedure for adjusting these?

 

I played with the reverse one and it seemed to make it easier to get the internal lever into the right position (which seems to push the brake band tight)

Edited September 8, 2010 by Chris Pink

[mykaskin]

 

The 2 threaded adjusters with locknuts in the picture, two used in forward (toggle lever screw) , one used in reverse (brake band lever adjusting screw)

 

What is the procedure for adjusting these?

 

I played with the reverse one and it seemed to make it easier to get the internal lever into the right position (which seems to push the brake band tight)

 

They need to be set such that it doesn't slip in use, and don't pop back out of gear. It shouldn't be too tight though. I don't think it matters which order you do them in as they are seperate adjustments. To turn the forward screws around to a suitable location for adjustment I found it easier to enguage ahead and turn the engine by hand - but then it's a hand start engine.

 

From the manual for my JP (blindly typed, so may have mistakes):

 

Ahead.

With the Reverse Control Gear Lever in neutral, remove the inspection cover, and turn the sliding sleeve, carrying the toggle lever round, until one toggle lever is at the top. Slack off the adjusting screw locknut slightly and screw in the adjusting screw one quarter turn. Without losing this setting, set up the locknut hard. Turn the sliding sleeve until the other toggle lever comes on top, and repeat the adjustment, being careful to obtain equal adjustment on both toggle lever screws. Engage Ahead Clutch. There should be an appreciable effort required to get it in (60-80 lbs. on the end of the reverse lever) but once in, there must be no tendency to jump out. It is important that there should be as little movement possible between the operating due and control sleeve with the geaqr fully engaged. With the Ferodo plates, "bedding in" of these takes place during the first few hours of operation and it is most important that the ajdustment be followed up until the clutch is fully "bedded in".

 

Astern.

Should there be any wear on the Brake Band the Gear will slip when engaged in astern. On the port side of the gear, under the Ispection Cover, an adjusting screw will be found on the Brake Band Lever over the tongue of the Brake Band. Put Hand Lever into neutral position, slacken the brake band lever adjusting screw locknut and adjust screw one 1/4 turn in a clockwise direction and secure locknet. Put Hand Lever into the astern position. When gear is now engaged astern the same effect should be required to engage the gear as felt after adjusting the ahead clutch. Should the lever tend to jump out of engagement, ease the Breake Band adjustment when the gear is in the neutral position. Should the gear still slip in astern, tighten the Brake Band Lever Screw to suit.

 

Cheers,

 

Mike

[MoominPapa]

Checking the manuals I have, the only thing I can add to what Mike provided is the stipulation that "there should be a well-defined neutral position".

 

MP.

[Chris Pink]

 

Ahead.

With the Reverse Control Gear Lever in neutral, remove the inspection cover, and turn the sliding sleeve, carrying the toggle lever round, until one toggle lever is at the top. Slack off the adjusting screw locknut slightly and screw in the adjusting screw one quarter turn. Without losing this setting, set up the locknut hard.

Astern.

Should there be any wear on the Brake Band the Gear will slip when engaged in astern. On the port side of the gear, under the Ispection Cover, an adjusting screw will be found on the Brake Band Lever over the tongue of the Brake Band. Put Hand Lever into neutral position, slacken the brake band lever adjusting screw locknut and adjust screw one 1/4 turn in a clockwise direction and secure locknut.

 

Thanks for that Mike, do you think these quarter turn instructions are from the position of having the adjuster finger tight?

 

Neutral is fairly obvious with the cover off but isn't where the notch in the locating plate is (and the locating plate won't adjust far enough to this position). The reverse position comes more or less at the end of the travel on this plate but the forward goes nowhere near the end of its travel. It sounds from this that the actual neutral would be astern of the notch but it's not, it's ahead of it.

Edited September 8, 2010 by Chris Pink

[mykaskin]

What is it you are trying to do Chris? If the brake band is slipping just put a little on the brake band screw to make it tighter. Is ahead OK, or does that adjusting as well?

 

Note that it's rare to get an exact neutral on these boxes as often the ahead cone can stick a little so a touch astern just to pull a little on the reverse brake band can break the sticktion, then put it in the middle again.

 

Is the 2G the one on the SR range - the JP has a 3R, which is what the instructions were from.

 

If in doubt just get the relevent manual for the box for a better understanding - they usually give a full operational description as well.

 

Mike

Edited September 9, 2010 by mykaskin

[Chris Pink]

What is it you are trying to do Chris?

 

When i took the inspection cover off - for an unrelated problem - I noticed that the difficulty in engaging reverse was aided by slackening off the brake band screw 1 turn. So I was wondering about the proper setting, which I guess will have to wait until the engine is fired up. Then I'll find out the balance between ease and reliability of selection. It did seem that the difficulty in engaging was due to the brake band hitting its stop.

 

Selecting forward seems easy enough although i am a bit worried about the complete non correlation between the position plate and what is happening inside the box.

 

The 2G is attached to an HA2.

 

It would be nice to get a manual, i must learn to put such meanness aside, rather than try and work it all out from first principles.

 

Which part is the cone? I have a parts list but that's not a term on there, do you mean the central clutch body, underneath the brake band?

Edited September 9, 2010 by Chris Pink

[MoominPapa]

Which part is the cone? I have a parts list but that's not a term on there, do you mean the central clutch body, underneath the brake band?

The 2G and 3G boxes don't have a cone, they have multiple clutch plates for the ahead clutch.

 

I've noticed that neutral is very difficult to find on a cold engine. The gear lever gets left in the exact position that ensured the prop wasn't moving when the engine last ran, but on starting from cold, the prop runs in reverse. As the gearbox warms up the balance of drag between reverse and forward seems to change, so the prop slows and then runs slowly forward. Eventually when it's all warm, there's a distinct neutral again.

 

MP.

 

Is the 2G the one on the SR range - the JP has a 3R, which is what the instructions were from.

The 2G on my FR looks identical inside to Chris's picture, and the instructions in my manual are word-for-word identical to the ones you posted.

 

MP.

[Chris Pink]

 

I've noticed that neutral is very difficult to find on a cold engine. The gear lever gets left in the exact position that ensured the prop wasn't moving when the engine last ran, but on starting from cold, the prop runs in reverse. As the gearbox warms up the balance of drag between reverse and forward seems to change, so the prop slows and then runs slowly forward. Eventually when it's all warm, there's a distinct neutral again.

 

I assume that the oil between the brake band and the clutch drum, which engages reverse, is causing sufficient friction when cold to bind them together slightly.