I have a so called dripless seal on my prop shaft on a 30ft Halvorsen Island
Gypsy. Ford 120 hp. All good until 1800 RPM and the thing dribbles like a
tap. Under 1800 RPM dry again. Had a hell of a time finding the leak. Not
much fun down the the bilge beside a 7 litre diesel at 1800 RPM ;-)
Interestingly the seal has a small water inlet line from the exhaust into
the seal for lubrication - this is a standard feature apparently. The whole
thing looks a bit fragile and fussy to me with only a single hose clamp
holding the rotating rubber seal to the shaft and up against the stationery
"female" part of the seal - I think I'll put an old time stuffing box back
on. Any advice?

thanks Shawn
"Scallywag"

Shawn,
I'm shooting in the dark here and am sure I'll hear about it, but could your
engine mounts be "giving" enough under higher RPMs and higher thrust?
MMC
"Shawn" wrote in message
...
I have a so called dripless seal on my prop shaft on a 30ft Halvorsen
Island
Gypsy. Ford 120 hp. All good until 1800 RPM and the thing dribbles like a
tap. Under 1800 RPM dry again. Had a hell of a time finding the leak. Not
much fun down the the bilge beside a 7 litre diesel at 1800 RPM ;-)
Interestingly the seal has a small water inlet line from the exhaust into
the seal for lubrication - this is a standard feature apparently. The
whole
thing looks a bit fragile and fussy to me with only a single hose clamp
holding the rotating rubber seal to the shaft and up against the
stationery
"female" part of the seal - I think I'll put an old time stuffing box back
on. Any advice?

thanks Shawn
"Scallywag"

If it is a PYI driplessI can invision two or three potential places to
look. First, as MMC said, if there is no thrust bearing between the
shaft and the engine it is possible that the thrust is pushing the
engine forward on its mounts. You can get harder mounts and live with
the extra vibration or loosen the set screws that hold the stainless
collar to the shaft. Push it a half inch towards the graphite seal to
compress the hose some more. Second, the graphite wear surface could be
scratched but that would usually leak at idle or low RPM. And third,
check how much vibration you are getting on the shaft. If the cutlass
bearing is worn and the prop fouled it could cahse the seal to wabble at
higher RPM.

The cooling water fitting is standard on faster power boat seals but not
on sailboat or slower displacement power boats.

Shawn wrote:
I have a so called dripless seal on my prop shaft on a 30ft Halvorsen Island
Gypsy. Ford 120 hp. All good until 1800 RPM and the thing dribbles like a
tap. Under 1800 RPM dry again. Had a hell of a time finding the leak. Not
much fun down the the bilge beside a 7 litre diesel at 1800 RPM ;-)
Interestingly the seal has a small water inlet line from the exhaust into
the seal for lubrication - this is a standard feature apparently. The whole
thing looks a bit fragile and fussy to me with only a single hose clamp
holding the rotating rubber seal to the shaft and up against the stationery
"female" part of the seal - I think I'll put an old time stuffing box back
on. Any advice?

thanks Shawn
"Scallywag"



--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

thanks guys
Will check engine mounts but my observation is that all is pretty stable at
cruising speed - shaft steady and very little vibration. I have compressed
the seal already a bit but will squish it up a bit more and see what
happens. Thanks for all your assistance.
regards Shawn

"Glenn Ashmore" wrote in message
news:AIUSc.27850$Jo1.18308@lakeread01...
If it is a PYI driplessI can invision two or three potential places to
look. First, as MMC said, if there is no thrust bearing between the
shaft and the engine it is possible that the thrust is pushing the
engine forward on its mounts. You can get harder mounts and live with
the extra vibration or loosen the set screws that hold the stainless
collar to the shaft. Push it a half inch towards the graphite seal to
compress the hose some more. Second, the graphite wear surface could be
scratched but that would usually leak at idle or low RPM. And third,
check how much vibration you are getting on the shaft. If the cutlass
bearing is worn and the prop fouled it could cahse the seal to wabble at
higher RPM.

The cooling water fitting is standard on faster power boat seals but not
on sailboat or slower displacement power boats.

Shawn wrote:
I have a so called dripless seal on my prop shaft on a 30ft Halvorsen
Island
Gypsy. Ford 120 hp. All good until 1800 RPM and the thing dribbles like
a
tap. Under 1800 RPM dry again. Had a hell of a time finding the leak.
Not
much fun down the the bilge beside a 7 litre diesel at 1800 RPM ;-)
Interestingly the seal has a small water inlet line from the exhaust
into
the seal for lubrication - this is a standard feature apparently. The
whole
thing looks a bit fragile and fussy to me with only a single hose clamp
holding the rotating rubber seal to the shaft and up against the
stationery
"female" part of the seal - I think I'll put an old time stuffing box
back
on. Any advice?

thanks Shawn
"Scallywag"



--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

I have a new cutlass bearing and a tested, dead straight shaft and a clean
prop
Shawn
"Scallywag'

"Glenn Ashmore" wrote in message
news:AIUSc.27850$Jo1.18308@lakeread01...
If it is a PYI driplessI can invision two or three potential places to
look. First, as MMC said, if there is no thrust bearing between the
shaft and the engine it is possible that the thrust is pushing the
engine forward on its mounts. You can get harder mounts and live with
the extra vibration or loosen the set screws that hold the stainless
collar to the shaft. Push it a half inch towards the graphite seal to
compress the hose some more. Second, the graphite wear surface could be
scratched but that would usually leak at idle or low RPM. And third,
check how much vibration you are getting on the shaft. If the cutlass
bearing is worn and the prop fouled it could cahse the seal to wabble at
higher RPM.

The cooling water fitting is standard on faster power boat seals but not
on sailboat or slower displacement power boats.

Shawn wrote:
I have a so called dripless seal on my prop shaft on a 30ft Halvorsen
Island
Gypsy. Ford 120 hp. All good until 1800 RPM and the thing dribbles like
a
tap. Under 1800 RPM dry again. Had a hell of a time finding the leak.
Not
much fun down the the bilge beside a 7 litre diesel at 1800 RPM ;-)
Interestingly the seal has a small water inlet line from the exhaust
into
the seal for lubrication - this is a standard feature apparently. The
whole
thing looks a bit fragile and fussy to me with only a single hose clamp
holding the rotating rubber seal to the shaft and up against the
stationery
"female" part of the seal - I think I'll put an old time stuffing box
back
on. Any advice?

thanks Shawn
"Scallywag"



--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

had the same problem on mine. No leak at slow speed but at 2400 had to pump
bilge every 2 hours. Changed the rear engine mounts and no more water.
Before doing that thought it might be engine allignment but it was less than
1000 out of line. Have a Yanmar and they do say to change mounts on a
regular basis


"Shawn" wrote in message
...
thanks guys
Will check engine mounts but my observation is that all is pretty stable
at
cruising speed - shaft steady and very little vibration. I have compressed
the seal already a bit but will squish it up a bit more and see what
happens. Thanks for all your assistance.
regards Shawn

"Glenn Ashmore" wrote in message
news:AIUSc.27850$Jo1.18308@lakeread01...
If it is a PYI driplessI can invision two or three potential places to
look. First, as MMC said, if there is no thrust bearing between the
shaft and the engine it is possible that the thrust is pushing the
engine forward on its mounts. You can get harder mounts and live with
the extra vibration or loosen the set screws that hold the stainless
collar to the shaft. Push it a half inch towards the graphite seal to
compress the hose some more. Second, the graphite wear surface could be
scratched but that would usually leak at idle or low RPM. And third,
check how much vibration you are getting on the shaft. If the cutlass
bearing is worn and the prop fouled it could cahse the seal to wabble at
higher RPM.

The cooling water fitting is standard on faster power boat seals but not
on sailboat or slower displacement power boats.

Shawn wrote:
I have a so called dripless seal on my prop shaft on a 30ft Halvorsen
Island
Gypsy. Ford 120 hp. All good until 1800 RPM and the thing dribbles
like
a
tap. Under 1800 RPM dry again. Had a hell of a time finding the leak.
Not
much fun down the the bilge beside a 7 litre diesel at 1800 RPM ;-)
Interestingly the seal has a small water inlet line from the exhaust
into
the seal for lubrication - this is a standard feature apparently. The
whole
thing looks a bit fragile and fussy to me with only a single hose
clamp
holding the rotating rubber seal to the shaft and up against the
stationery
"female" part of the seal - I think I'll put an old time stuffing box
back
on. Any advice?

thanks Shawn
"Scallywag"



--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com