We have a Volvo
2003, it had the big 6 rubber volvo
flexable coupling and a standard packing gland
when we brought the boat. The engine
received new volvo rubber mounts when we brought the boat.
Noticed some of the rubbers in the coupling where showing damage and after checking out the price
suggested a R&D coupling. We tried that but noticed a lot more vibration in the boat so switched back to the volvo coupling which it would seam is more flexible.
Though all this time the packing gland
was a ass to adjust, either getting hot or letting in excessive water
so we thought it would be a good idea to replace it with a PSS face seal.
Fitted the PSS seal and found that the shaft was bouncing on the stern tube at certain rev's, the old packing gland was obliviously acting as a forward bearing for the shaft.
Tried using a rubber cutlass bearing as a forward bearing in the system but that only lasted a hundred hours before the rubber was destroyed.
Changed back to the R&D coupling to eliminate some movement but still a problem. It seems the 2003 volvo is very softly mounted and even revving in neutral the shaft hits the stern tube at certain revs. The alignment has been done several times.
Thought about replacing the mounts with something harder but new brackets would have to be made for the front of the engine
as the front ones are not compatible with aftermarket mounts.
Does anyone know what the clearance should be between the shaft and stern tube? Can anyone offer any ideas for a possible solution?