L23 Diesel Engine Removal and Refurbishment

Leisure 23SL

Removing a Volvo Penta MD2001

For Refurbishment or Saildrive 

Diaphragm Replacement

Part 1

I must start by saying that my forty four year old MD2001 

has never let me down or missed a single beat in my ownership - apart from when she sucked a plastic bag up 

the water intake halfway across the Thames estuary - 

but that’s a story for another day!

She has reliably plodded away continuously for 10 hours 

against a Force 5 gusting 6 on the nose, all the way from 

Aldeburgh in Suffolk down to Bradwell in the Blackwater 

and didn’t complain once. So, what I am trying to say is: 

these are reliable engines - if properly looked after.

Last season, as Sirius and I approached our fifth anniversary together (during which time we have covered a fair few sea miles, cross-crossing the Thames estuary between Lowestoft, Ramsgate and the Medway), I began to notice a few drips of oil in the bilge under the engine - 

nothing serious but something to keep an eye on.

By the end of the 2025 season I decided that it was time to act, having reasoned (wrongly as it later turned out) that the rear crankshaft oil seal was wearing hence the 

drops of oil.

So I needed to bite the bullet, remove the engine over the winter and give it a thorough inspection, replacing and rebuilding as necessary.

As I said previously, the engine had already given forty four years of steady, uncomplaining service so a bit of preventative maintenance and TLC before anything went seriously wrong, was due.

The usual internet searches and even our trusty LOA website failed to come up with any definitive information on the job, so I decided to get stuck in and literally ‘do it myself’!

Thoughts before Engine Removal

What follows is what I did. It may not be the best way but it worked for me. Nobody got injured. Nothing got damaged. However, if you do decide to have a go yourself, please remember that moving a hefty 126 Kg (277lb ) lump of metal is involved.

The potential for injury and disaster is very real. Think hard and be sure to protect yourself, your boat and any colleagues (should any turn up to help! They were noticeable by their absence in my case!).

1.The companionway will be about 16 inches at its widest

2.The engine will be about 17.3 inches from side to side.

3. The engine will be about 14.5 inches front to back (measured to where it joins the gearbox/saildrive).

This means:- the engine must be rotated through 90 degrees for it to pass through the companionway opening. It is a lot like delivering a baby, a lot of hot, heaving and pushing with a gentle turn at the end!

Preparation 

(Using the layout I have on Sirius)

Have the boat craned out and placed securely on the hardstanding in the boatyard.

Run the engine up to temperature (with a hose supplying cooling water) for 10 mins. Then shut down.

Remove the companionway steps.

Pump out the warmed engine oil into a suitable (2ltr) container. Be careful the oil is not too hot and dispose of it responsibly at the local council tip.

Disconnect and remove the starter and domestic batteries.

Removed the battery isolator switches from the Starboard side of the companionway (along with the Nasa battery monitor shunt).

Disconnect the raw water intake hose, the raw water filter and the engine water feed hose from the port hand side of the companionway.

Switch off the diesel fuel feed and disconnect from the Primary Fuel Filter/Water Separator. Disconnect the diesel hose which goes to the lift pump.

Unbolt, drain and remove the primary filter assembly from the port hand side of the engine space.

Carefully disconnect the diesel pipe from the injector pump to the injector (wrap the ends to keep them clean).

Remove the fine fuel filter together with its mounting bracket and various diesel feed and drain pipes. (Keep all ends sealed to keep dirt out of the fuel lines.

Carefully disconnect the throttle and engine shut-off cables from the port side of the engine (retaining all the brackets and nuts and bolts).

Reach behind the engine and remove the air filter

Move around to the starboard side of the engine (accessed via the very snug cockpit sail locker) and remove the negative cable and the positive cables that supply the starter, starter relay and alternator.

Unplug and disconnect the wiring loom from the rear of the starter relay mounting bracket.

Now disconnect and remove the exhaust hose from the end of the exhaust elbow casting.

Unbolt the four bolts holding the exhaust elbow to the engine casting.

You will not be able to withdraw the bolts fully because they will hit the underside of the cockpit sole just undo them.

Next with a blunt chisel and soft hammer persuade the exhaust elbow gasket to let go and release the elbow.

If you do not do this now you will not be able to lift the engine high enough for the flywheel housing to clear the engine beds when you attempt to rotate and withdraw the engine! (the 50mm extra height gained under the cockpit sole will make all the difference - ask yourself how I know this!)

You will also probably end up hacksawing the exhaust hose off. Mine was seized solid.

At this point most of the preparation work is done. Just a few more things to do.

Ensure that the saildrive is securely supported with blocks of wood so that it cannot drop out of line when the engine and gearbox are separated.

Fabricate a temporary floor

I also fabricated an 18mm ply ‘floor’ which sat just under the sump and out into the companionway.

It was supported on stout blocks to raise it clear of the sea water intake cock in order to protect it.

You do not want to accidentally dump the whole weight of your engine on top of the sea cock. It will simply drive the cock straight through the bottom of the hull!

In the event, although the ‘floor’ did protect the sea cock it was not of much use in actually manoeuvring the engine.

Now locate and remove the three bolts on each side of the gearbox which hold the gearbox/saildrive and the engine together.

Remove the two bolts from each of the engine mount legs which hold the mount bases to the engine beds.

Remove the instrument panel above the top companionway step (Oil gauge, voltmeter etc) and disconnect any sensors and wires, then remove the top companionway step.

You are now finally ready for the engine lift -out and removal.

Engine lift out and removal.

Ignore some internet information!

On the internet I came across several accounts of people claiming to have used their main sheet tackle and the boom (suitably supported?) to haul the engine up and out into the companionway and eventually to the cockpit.

My advice is to totally disregard these accounts!  It may be possible IN EXTREMIS, but in my opinion it is far too dangerous to attempt so please don’t do it!

The proper and safe way to proceed is:- Buy, beg or borrow a proper chain hoist with a safe working capacity of at lease 500Kg, then attach it to a length of 3”x 3”(minimum) hardwood supported on blocks positioned either side of the main hatch so the chain hoist dangles down into the companionway.

Construct a rope strop with several passes of good 10 or 12mm rope by passing it through the two lifting eyes on the engine and securing it firmly.

One lifting eye is a metal bridge between the thermostat housing and the fine fuel filter bracket on the front left hand side of the engine as you look at it.

The other is a plate with a circular hole that is bolted to the engine block behind the air intake at the rear right hand side of the engine as you look at it.

The strop will run diagonally across the top of the engine.

Attach the chain hoist hook to the strop. Gently take up the slack on the chain and strop.

Now it is time to disengage the engine and gearbox by pulling the engine carefully forward about 40mm along the engine beds so it slides off of the splined gearbox drive shaft. This is brutal work!

Be careful not to let the engine slip left or right off the engine beds or to skid forward off the ends. I enlisted the ‘grunt’ of my twenty stone powerlifting boatyard owner Adrian for this bit!)

Once the engine and gearbox are separated, gently take up the weight of the engine with the chain hoist.

With luck a little bit of magic happens now! As the engine rises, the bottom of the flywheel housing clears the engine beds (which would not be possible if the exhaust elbow was still attached!).

Because the strop is diagonal the tension of the chain hoist causes the engine to rotate clockwise through 90 degrees. It will swing out into the companionway under the main hatch.

Gently lower the engine onto the cabin sole (suitably protected by plywood or hardboard) and support it while freeing the chain hoist from the cross hatchway timber

Re-attach the chain hoist to the strop or lifting hook from the yard crane.

Carefully guide the engine out through the hatch as the crane lifts - but take care not to find yourself directly underneath it at anytime, just in case!

And that my Leisurely friends is how I removed my Volvo Penta MD2001!

Still to come:  In Part two 

I will detail moving the engine into the workshop and giving it a careful once over to assess and prioritise the necessary work before stripping it down and starting work.