Practical Boat Owner — January 2018

YANMAR ENGINE REBUILD

had our research on the internet shown
that this product had been used
successfully in the automotive industry for
long-term repairs, but we were also
drawing on Alan’s lengthy and first-hand
experience of using a similar product.
Repairs to Volvo six-cylinder engines
which had suffered corrosion between the
two cylinder heads had proved successful
in the long term, as had his repair to a
large torque converter casing where a
loose bolt had indirectly caused the main
oil gallery to burst.

So the burned pit in our head was

thoroughly degreased, the filler was

applied and, once cured, was flatted off to

make an effective repair.

Back together again

The engine was then re-assembled with

new filters, hoses and copper washers,

and although having complete faith in the

work done, we decided to run it up on a

test bed at home before reinstalling it on

the boat.

The whole unit was cleaned up and

Barri Hopkins sailed the

shallow waters of the East

Coast creeks and rivers for

the past 27 years, mostly

single-handed. He learned

to sail in his first boat, a twin-keel

Seawych, but advancing years

demanded standing headroom and an

inboard engine, so he graduated to the

Leisure 23SL which he still has today.

Aged 14, Alan Cowper

helped build, and then

sailed, a Mirror dinghy at

school. In 1975, he installed

a Petter Mini 12 in a friend’s

wooden boat and sailed this in the

waters around Mersea Island. More

recently, he has again cruised the

Mersea waters – this time in Barri’s

Leisure 23SL, Funadama.

ABOUT THE AUTHORS

Finished engine is craned back aboard

Northern Light at the boatyard

Temporary sloping platform allowed the

engine to simply slide back into place

Steel-reinforced epoxy was considered
strong enough for the block repair

given a few coats of spray paint – a vast

difference from the sick, rusty heap we

hauled out of the boat.

The engine started first time and ran

smoothly. The only slight hiccup was a

weep from the water pump shaft, so the

seals were subsequently replaced.

The lift back into the boat was done by

the yard’s crane. To facilitate this task, and

to make easier the job of placing the

engine on its beds, a sloping platform was

fabricated on which the lowered engine

sat on its sump. Careful measurement had

ensured that the engine could then simply

be slid aft onto its beds. Job done!

The rebuilt engine

is plumbed up for a

test run before being

reinstalled in the boat