How do I remove and refit the saildrive seal on an Arcona 400?
My 2008 Arcona 400 has a Volvo Penta D2-40 with a 130S saildrive. The hull seal is now 8 years old, so it's time for a replacement before the insurance company complains. What is the proper procedure for getting the drive out and fitting the new diaphragm?
Answer
Replacing the saildrive seal on an Arcona 400 requires sliding the Volvo Penta engine forward on its bed and lifting the saildrive unit into the cabin to swap the rubber diaphragm. Expect to spend a full weekend on the job and around £250 for the genuine Volvo Penta seal kit.
Preparation and Draining
Before starting, the boat must be ashore. Remove the folding propeller, zinc ring anode and the external rubber fairing flap from the underside of the hull. Drain the gear oil by removing the large flat-headed plug at the bottom of the saildrive leg. Inside the cabin, isolate the batteries. Disconnect the raw water intake hose, gear shift cable and any electrical bonding wires attached to the saildrive.
Moving the Engine Forward
On the Arcona 400, the Volvo Penta D2-40 and 130S saildrive combination sits in a well-proportioned engine box. You must move the engine forward to separate it from the drive. Disconnect the exhaust hose and fuel lines if they lack slack. Unbolt the six 17mm bolts securing the engine bell housing to the saildrive. Next, unbolt the front engine mounts from the GRP stringers. Leave the central adjustment nuts untouched so you do not lose your engine alignment.
Support the rear of the engine block securely with timber and a small scissor jack before unbolting the rear mounts. Never work around an unsupported engine. Slide the engine forward by 150mm until the splined shaft is completely free of the saildrive.
Extracting the Saildrive
The rubber diaphragm is clamped to the hull bed by a heavy galvanised steel ring. Unbolt the eight M8 bolts (usually requiring a 13mm socket) and lift the ring away. The saildrive unit can now be hoisted straight up into the cabin. It weighs 30kg. This is manageable for two people, but lay down heavy cardboard to protect the teak and holly cabin sole.
Lay the drive on its side. To remove the old seal, you must split the saildrive leg. Undo the bolts connecting the upper gear housing to the lower leg and pull the two sections apart. Slide the old rubber diaphragm off the upper housing.
Fitting the New Diaphragm
Clean all mating surfaces meticulously. Remove any old salt deposits or corrosion. Do not use wire brushes on the aluminium. Stick to a green Scotch-Brite pad and brake cleaner.