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Barry's Blog #140 - The big test

With the propeller shaft back in place and coupled to the back of the gearbox, it was now time to reattach the air intake/turbo/exhaust system components back onto the engine. In theory it all sounds so simple. Place the unit in position, tighten up four nuts, clip on the air filter, bolt on the exhaust mixing elbow and reconnect the various hoses. In practice the job took 5 hours.

A diesel engine sitting on a bench in a workshop is easy to work on. You can walk all around it, you can get your hands in from any position, if you drop a spanner or a nut you can just bend down and pick them up off the floor and the workshop will generally be well lit and airy. None of those things apply when you're working on an engine that's attached to a boat in a Greek boat yard in summer.

The lighting is very poor, the heat is ridiculous and getting those first four nuts onto the bolts requires skills that Houdini would be proud of.

At first the unit did not line up with the four bolts so it would not slip into position. This was resolved by taking the unit back out into the cockpit, loosening four other bolts to allow slight rotation of a part and then attaching it to the engine block.

With the rotating part now rotatable we lined up the four bolts and screwed the only easy to get to nut onto the bolt to take the weight of the unit. Next the rotating part was lined up so that it was able to connect to the hose near the sump of the engine. With that connection done we could now re-tighten the four bolts of the rotating part. Of course now we didn't have the luxury of easy access for the spanner and more Houdini moves were in order.

I won't bore you to death with a complete blow by blow account of the refitting process but from what I've described so far you can probably understand why it took 5 long, hot, sweaty, hours.

The impeller

There are some things you don't know until they're pointed out to you and it was only after 8 months of A B Sea being out of the water that one of our subscribers commented that we should have removed the impeller on day 1 of being on the hard and kept it in a jar of fresh water to prevent the rubber going hard and brittle.

The impeller housing is not a perfect cylinder and with the little rubber arms sitting in a distorted position for 8 months they had bent out of shape and rendered the impeller useless. Time to fit a new one before the big engine test.

Following a suggestion from another subscriber I reduced the length of the centre bolt of the impeller puller and managed to get the tool in position behind the starter motor. After a bit of a struggle I got the impeller out of the housing and saw the bent out of shape arms and understood why it's best removed at the beginning of any down time and stored in a jar of water. It was so badly misshapen that it wasn't even worth keeping as a backup spare. Lesson learned.

The big test

This moment had been running through the back of my mind every day for 8 months. Would the heart of A B Sea fire up once we'd put it all back together? There was only one way to find out.

On yachts the diesel engine is cooled by sucking in raw seawater, passing it through a heat exchanger where narrow pipes containing seawater pass by another set of narrow pipes containing freshwater. The two exchange the heat from the engine and the now hot saltwater is pumped into the exhaust mixing elbow where it mixes with the diesel exhaust gasses before both are spat out of the back of the boat.

As A B Sea was still on the hard, in the boat yard, we were missing the vital component of seawater. We prepped as best we could with a hosepipe, a header tank and a couple of buckets full of fresh water. With everything ready and fingers crossed I instructed Aannsha to "Fire her up."

I heard the usual beep and then nothing. Literally nothing. Not even the sound of a starter motor solenoid clicking indicating a flat battery. Bugger.

I knew that the starter battery was fully charged because we were attached to shore power and I'd been monitoring it for several days. The first place to look was the starter motor. Just like when a computer tech asks you if you've tried switching it off and turning it back on again, that's the approach I took. I disconnected the electrical cables, cleaned the connections and reattached the cables.

Engine start attempt number two. As I stood by with water at the ready, Aannsha turned the key. The usual beep was instantly followed by the familiar roar of the engine bursting into life. The plan was to keep the engine running for as long as possible to make sure there was no air in the fuel line.

The engine ticked over, I dumped freshwater into the intake as the engine sucked it dry. Aannsha confirmed that water was indeed pumping regularly out of the exhaust. I didn't want to let the engine get too hot. After only a couple of minutes I called to Aannsha "OK. Shut her down."

I cried

It was a truly emotional moment as 8 months of stress and worry lifted off my shoulders. I had tears of relief in my eyes.

The work we'd done had been done correctly and the jigsaw puzzle was finally completed. There were still a few things to do before we splashed, but A B Sea had a working heart.

As you'll see in the YouTube video that accompanies this blog, there's a bit of a debrief over a couple of cold beers with my hands still filthy from working on the engine and blood still seeping from my latest boat bite. But we did it, we had success and we're wiser for it.

Leave a comment or question on the video and make sure you click the subscribe button and bell icon so that you get notified when we release our next video where A B Sea gets put back where she belongs.

To watch the video that accompanies this blog click here.

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