Hi all What is a "cone"

[redbreast]

Hi all What is a \"cone\"

Having trouble engaging gear , just reving then engaging with a klunk . Our engineer tells me could be the cone to look at next. and that the boat might need to come out the water again "thought after adjusting the linkage on land and testing" should have solved the problem . Any thoughts please ?

 

[Lakesailor]

Re: Hi all What is a \"cone\"

A Google search brought this pretty good explanation.
[ QUOTE ]
A cone clutch consists of a male and female cone. One cone (often the male) is fitted with some form of "friction" material. This can be similar to car brake linings, but suitable for use in oil, or bronze or cast iron. These are usually of sintered construction (powder is put into a mould and subject heat and pressure to partialy "reform" it). If your gearbox is more than 30 years old I would suspect it to have "brake" lining, and newer boxes are likely to use sintered material - but this is a very general comment.

You will have one half of the clutch splined to the gearbox shaft and the other half fitted to the gear. When the clutch is engaged it locks the gear to the shaft.

[/ QUOTE ]

So in short it's a clutch with a very "on-off" action.

 

[billskip]

Re: Hi all What is a \"cone\"

Quote

just reving then engaging with a klunk

___________

Is it a single lever control? if so the engine should remain at the same revs as on "tickover" when the clutch engages. ok maybe a slight increase in revs but not "Revving"

Maybe I am misunderstanding

 

[Richard10002]

Re: Hi all What is a \"cone\"

My revs reduce slightly when the cone engages, (I've been told I've got a cone on a VP MD22L??). Seems to make sense as the engine now has to turn the shaft and prop.

 

[mont]

Re: Hi all What is a \"cone\"

FWIW ....
After much needless expense etc .....
I'd still be looking for poor adjustment, slack in the cables or lever unit sloppy etc. Its a fine line if your still poorly adjusted or the cables / levers are shot.
Without wishing to say your engineer is wrong your scenario can easily be caused by this still - mine were - new clutch (engineer recommended) didnt change anything !
First push on lever (quarter) only moves the gear cable - or should, but with poor adjustment it may not go full travel. After that its throttle only.
You may think that the clutch only gets engaged when the revs come on but it can be that last bit of adjustment / slack when you push beyond the 'quarter' stop which gives full movement down to the gearbox.
I'd dis engage the throttle cable at the lever or pump and check for full movement of the gear cable at quarter and then beyond. Start the engine, now only running at tickover and see if it engages when lever is beyond the quarter stop. If this works ok, then as you will only have tickover, then it aint the clutch its adjustment.
This will at least isolate the problem to the 'cone clutch'.

 

[Tim777]

Re: Hi all What is a \"cone\"

If it helps this is a sliding sleeve (290 duoprop) which travels up or down to engage the cone for forwards or backwards.

As a rough rule I believe that if you have good gear engagement in one direction but poor in the other then a cone / sleeve wear problem is indicated. If the gears engage equally poorly in both directions then a fluid or cable problem is likely.

 

[Risingstar]

Re: Hi all What is a \"cone\"

Just had exactly the same problem. As others have said, check all the adjustments first. Then we renewed the cables. Next stage was taking the drive apart. Hope you have more luck, we've had to order a new drive.

 

[Col]

Re: Hi all What is a \"cone\"

Assuming Volvo, they can & do wear the clutch cone. Before you start ripping the drive off, Check the oil level (and type) in the drive 1st.
If you have too much oil (or water in the oil which raises the level) it can give you the same symptoms. Check the adjustment of gear cable / linkage(best done out of the water so you can see what's going on)
Take the rear rectangular(ish) cover off, you will see a "rocker" that sits horizontally in neutrel and rocks left or right with gears in fwd / rev. Make sure it's horizontal in neutrel.
The props should Lock in one direction when in gear and turn freely both ways in N. You could pull the split pin and turn the rocker by hand to see if that makes a difference. After that, It's stripdown time

 

[rlw]

Re: Hi all What is a \"cone\"

Hi

Personal experience has shown the cone needs to be replaced at around 1000 hours on a duoprop drive. Slipping before engaging sounds familiar. Costs about 1000 GBP for a drive.

rlw

 

[volvopaul]

Re: Hi all What is a \"cone\"

One more cause to add and this has happened before.

The cone is pushed up or down by a sliding shoe, now this is in contact with the cone all the time, it wears out obviously in the forward direction more than in reverse because the cone is spinning and the shoe is stationary, they come as a pair when you order a new cone, get your engineer to remove it and check before ordering the lot, it can be changed without removing the whole of the leg, just remove the top housing from the bellows, you have to remove the top housing anyway even if the whole leg has been removed.

 

[tcm]

Re: Hi all What is a \"cone\"

hm. It clearly sounds as tho some berk has put an ice cream cornet in your gearbox. Technically, the cone is the wafer bit.