4 May 2021

CAUTIONERY  TALE No.1 – By Mike Lucas
Stern glands – Pre-launch preperation

Article from Sadler Owner’s Magazine, January 2001

1) STERN GLANDS – PRE-LAUNCH PREPARATION
There are a number of different types of shaft glands fitted to Sadlers and Starlights and some of
the later types do give cause for concern, if the right preparatory action is not taken prior to
launching.
First of all, let me say that the traditional style shaft gland with packing and provision for injection
of grease does not pose a problem and this is the way all the early Sadlers were done until about
1982. From about that time, Sadlers were fitted with a “no maintenance” type of shaft gland using
an oil reservoir and neither do these pose a threat at launching.
The problem arises with the Deep Sea Seal which holds back the water as a result of finely
machined and adjusted contact faces and also with the Volvo seal which uses a rubber boot with
integral neoprene rings. A fundamental requirement with both the last two types of seal described,
is to allow the water to dribble through the gland when first launching. If you look at the instruction
leaflet, you will find that with a Deep Sea Seal, you should ease the two surfaces apart until the
water dribbles through and then allow them to go back again through natural pressure of the
rubber boot. Once lubricated, the seal is satisfactory for the rest of the time the boat is afloat and
requires no maintenance at all. The same procedure should be applied to the Volvo seal, except this
is achieved by squeezing firmly the rubber boot, thus distorting slightly the neoprene ring seals and
allowing the water to dribble through. Once this job has been done, the seal is entirely maintenance
free.
These maintenance-free seals were fitted to all Sadlers from about 1989 and most of the Starlight
35s. The Starlight 39 was fitted with a traditional stuffing box type of shaft gland, which requires
normal maintenance, but no necessity to allow the water to flow before launch.
We are bringing this to your notice because we have become aware of two local Sadlers with Deep
Sea Seals, which were launched by owners who were unaware of the correct procedure. The result
in both cases was for the rubber boot to disintegrate, thus allowing water to flow in, which if
undetected would have swamped the boat. Most owners are aware of the launch procedure, but do
check which seal you have and refer to the maintenance instructions.
Cutlass bearing useful tip
It is worth mentioning that the prop shaft should be drawn out periodically and cleaned up in the
area of the cutlass bearing. This section of the prop shaft contained within the cutlass bearing will
invariably have built up a “crust”, which accelerates wear in the cutlass bearing and also on the
shaft itself. Once the shaft is drawn out from the cutlass bearing, this can be thoroughly cleaned
and then re-assembled. This also gives the opportunity to check the coupling with its fastening
bolts, to clean off surplus rust and ideally paint over with a rust preventative paint, such as
Hammerite. We plan to write a technical article about cutlass bearings and ‘P’ brackets in due
course.