Problems with PSS shaft seal Type A

[All_at_Sea]

Has anyone else had this problem that when going above 1800 revs the shaft seal leaks like a sieve! It appears that at higher revs the shaft must be being pushed forwards slightly, enough to allow more water in than l would like!

I spoke to the guys and they said it needs more adjustment but shouldn't this have been done at the beginning or is this a sign of wear, its only three years old? and it means an out of the water adjustment as the screws holding the the metal rotor collapse on installation, so l need new ones for the adjustment.

This isn't a job l was ever expecting to do!

 

[MoodySabre]

Never had that problem in 8 years. Your engine mounts must be soft or loose as there is no other way it could move forward.
If you need to compress the gaiter more then get some spare screws from Silette. Put a jubilee clip on the shaft to stop the rotor moving. Then you can take the old screws out whilst in the water and compress the gaiter.

 

[BabaYaga]

Has anyone else had this problem that when going above 1800 revs the shaft seal leaks like a sieve! It appears that at higher revs the shaft must be being pushed forwards slightly, enough to allow more water in than l would like!

I spoke to the guys and they said it needs more adjustment but shouldn't this have been done at the beginning or is this a sign of wear, its only three years old? and it means an out of the water adjustment as the screws holding the the metal rotor collapse on installation, so l need new ones for the adjustment.

This isn't a job l was ever expecting to do!

Sounds to me as something has given way and slipped since the installation. Either the rotor on the shaft or possibly the rubber bellows on the stern tube.
I recently replaced the bellows after 16 years without any issues. I found that when the new bellows was compressed by moving the rotor the distance stated in the manual, it was very well compressed.

 

[superheat6k]

Not a problem to adjust the tension in the water.

Position a jubilee clip just behind the rotor so it can't slip backwards. Loosen the two pairs of grub screws (NB PSS recommend renewing the inner grub screw after one use).

I use a piece of stud bar and a small 90o bracket clipped to the shaft with another jubilee clip. Position the stud bar so it sits snugly between the bracket and the rotor with a nut loading it against the bracket, then using a pair of nuts locked together, simply wind the stud bar to load the seal into a tighter position.

I would suggest trying 10mm and see if this relieves the problem.

 

[Stemar]

The first question for me would be, was the compression done properly in the first place? My plan A would be to try again according to the fitting instructions.

As a little aside, I had a stuffing box that I could not stop leaking. There was always water in the bilge under the engine. I finally gave up and fitted a PSS seal at great expense. No signs of leakage from it, but still water in the bilges. That was when I finally noticed a drop of water running down from one of the cooling water inlet mounting bolts...

 

[smithy]

There is an overall compressed length given on their website which might be easier to use. This will give you a give you rough check, especially with the boat in the water. I made up this tool to help with compression.

 

[All_at_Sea]

The first question for me would be, was the compression done properly in the first place? My plan A would be to try again according to the fitting instructions.

I assume so, it was done professionally at Portland marina. But l am beginning to think it wasn't compressed quite enough originally....

 

[PWLS08]

I also never had a problem with such a leak, though we did have a drip in lockdown which it was suggested was due to crystallization or some other foreign matter separating the faces, it disappeared after the first run out post lockdown.

 

[peteK]

I had recent stern gland leak and It was due to a small piece of fishing net wrapped around the propeller boss.