howard21
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What would cause a Bravo Outdrive to engage into gear slowly? Engages into reverese OK but has a long hesitation when placed into drive position.
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Question about outdrive
- Thread starter howard21
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Schi-502
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Cable adjustment!
LAZY SHIFT
QUESTION: I have a 2005 32-foot Advantage Victory with twin MerCruiser 496 Mag HO engines and Bravo One X drives. The starboard drive is very slow to fully respond to the shifter at the helm. When shifting into gear in reverse and forward, the prop begins to spin immediately, however, it spins with very little power.
It takes 5 to 10 seconds and then the clutch locks up and the boat responds appropriately. The port drive responds immediately as did the starboard drive prior to having it serviced. I recently had the drives serviced, which included removing them, checking the alignment and replacing the drive oil.
The problem with the starboard drive started shortly after servicing with a brief delay that has grown to 5 to 10 seconds. I had this same problem with the port drive a year ago, but was unable, at the time, to link it to drive service due to some other factors, although the drives were serviced within the time frame of the problem. The shop ultimately replaced the cone clutch assembly in the port drive unit.
Is it possible that there is actually air in the starboard drive unit that has accumulated creating an air pocket that is preventing full engagement rather than a problem with the cone clutch assembly?
Do you have any other suggestions as to the cause of the problem, diagnosis and the fix for it before I replace another cone clutch assembly? I always enjoy your section in Powerboat.
ANSWER: There is no way that it?s related to air in the drive. A Bravo drive is a wet-sump drive and is filled to the midpoint of the upper input shaft. When the engine is running, the upper pinion gear and the driven gears are always in motion. When the cone clutch is engaged, one of the driven gears is locked to the upper shaft, which is coupled to the lower vertical shaft. When the lower driven gear is engaged, the propeller spins clockwise, and when the upper driven gear is engaged, the propeller spins counterclockwise.
There are brass rings attached to the two driven gears. When the drive is assembled, the driven (forward and reverse) gears must be timed in order for the cone clutch to shift properly. The brass rings are high on one side and low on the other so there is a ?wobble? when they rotate. The shifting fork that rides in a slot in the cone clutch goes between the two brass rings on the gears. The shifting fork also has some cam ramps on it that contact the brass rings. When the drive is shifted, the uneven motion of the brass rings helps to kick the cone clutch into an engaged position.
I don?t believe your problem is from having the drives serviced unless they put the wrong oil in the drives. I believe that the brass rings on the gears may be worn or there is a problem with the shifting fork or cams. There?s a possibility that the problem is only being caused by the shifting fork or the linkage that connects to the intermediate shift cable. There is a setscrew on the shift shaft that also might have come loose. Remove the back cover from the drive to inspect the linkage, shift fork and the setscrew.
It?s possible that the intermediate shift cable wasn?t properly engaged in the shift linkage when the drive was reinstalled on the boat. It is sometimes tricky to get the linkage to latch on the cable end. To inspect that connection, the drive will have to be removed. The linkage is connected to the drive?s starboard side. It must be unlatched to remove the drive fully.
If all of the shifting mechanism is in good order, it is likely that you will need to replace the cone clutch and shifting fork. If the brass rings on the driven gears are excessively worn, replacement of the upper gear set also will be necessary. If there is any metal on your upper plug magnet, there is a possibility that the thrust bearing is failing. The debris that is generated can cause the cone clutch to act weird.
Credit goes to Bob Teague and a different boating forum.:skull
http://powerboatmag.com/questions-concerning-drives.html
http://www.offshoreonly.com/forums/drives-lower-units/233258-5-second-delay-bravo-xr.html
QUESTION: I have a 2005 32-foot Advantage Victory with twin MerCruiser 496 Mag HO engines and Bravo One X drives. The starboard drive is very slow to fully respond to the shifter at the helm. When shifting into gear in reverse and forward, the prop begins to spin immediately, however, it spins with very little power.
It takes 5 to 10 seconds and then the clutch locks up and the boat responds appropriately. The port drive responds immediately as did the starboard drive prior to having it serviced. I recently had the drives serviced, which included removing them, checking the alignment and replacing the drive oil.
The problem with the starboard drive started shortly after servicing with a brief delay that has grown to 5 to 10 seconds. I had this same problem with the port drive a year ago, but was unable, at the time, to link it to drive service due to some other factors, although the drives were serviced within the time frame of the problem. The shop ultimately replaced the cone clutch assembly in the port drive unit.
Is it possible that there is actually air in the starboard drive unit that has accumulated creating an air pocket that is preventing full engagement rather than a problem with the cone clutch assembly?
Do you have any other suggestions as to the cause of the problem, diagnosis and the fix for it before I replace another cone clutch assembly? I always enjoy your section in Powerboat.
ANSWER: There is no way that it?s related to air in the drive. A Bravo drive is a wet-sump drive and is filled to the midpoint of the upper input shaft. When the engine is running, the upper pinion gear and the driven gears are always in motion. When the cone clutch is engaged, one of the driven gears is locked to the upper shaft, which is coupled to the lower vertical shaft. When the lower driven gear is engaged, the propeller spins clockwise, and when the upper driven gear is engaged, the propeller spins counterclockwise.
There are brass rings attached to the two driven gears. When the drive is assembled, the driven (forward and reverse) gears must be timed in order for the cone clutch to shift properly. The brass rings are high on one side and low on the other so there is a ?wobble? when they rotate. The shifting fork that rides in a slot in the cone clutch goes between the two brass rings on the gears. The shifting fork also has some cam ramps on it that contact the brass rings. When the drive is shifted, the uneven motion of the brass rings helps to kick the cone clutch into an engaged position.
I don?t believe your problem is from having the drives serviced unless they put the wrong oil in the drives. I believe that the brass rings on the gears may be worn or there is a problem with the shifting fork or cams. There?s a possibility that the problem is only being caused by the shifting fork or the linkage that connects to the intermediate shift cable. There is a setscrew on the shift shaft that also might have come loose. Remove the back cover from the drive to inspect the linkage, shift fork and the setscrew.
It?s possible that the intermediate shift cable wasn?t properly engaged in the shift linkage when the drive was reinstalled on the boat. It is sometimes tricky to get the linkage to latch on the cable end. To inspect that connection, the drive will have to be removed. The linkage is connected to the drive?s starboard side. It must be unlatched to remove the drive fully.
If all of the shifting mechanism is in good order, it is likely that you will need to replace the cone clutch and shifting fork. If the brass rings on the driven gears are excessively worn, replacement of the upper gear set also will be necessary. If there is any metal on your upper plug magnet, there is a possibility that the thrust bearing is failing. The debris that is generated can cause the cone clutch to act weird.
Credit goes to Bob Teague and a different boating forum.:skull
http://powerboatmag.com/questions-concerning-drives.html
http://www.offshoreonly.com/forums/drives-lower-units/233258-5-second-delay-bravo-xr.html
