Repowering Anju - Part 1

13th September -  24th October 2007

After four long, hard months overhauling Anju's hull and rebuilding the interior, we decided to put ourselves through the turmoil again and continue our refit by re-powering Anju with a new 54 hp Yanmar engine.    Our trusty, old (true age never determined) 30 hp Yanmar 3 cylinder diesel, named Yanny, had served us well but was somewhat underpowered for our 20 tonne steel boat.    Although Yanny was still running perfectly well, we felt that now was the time to re-power while we were already in the yard and had expert advisors nearby, to avoid the possibility of spending further extended yard time, possibly in more expensive and less convenient locations, if installing a new motor were to become unavoidable later.   Even though our decision had been made, it was still hard to say goodbye to Yanny after all his loyal service.   It was strange how attached we had become to our motor!

So, the local Yanmar mechanic was summoned for a quotation for removal of the old engine and purchase and installation of the new 4JH4AE, 4 cylinder diesel.   The good news was the cost of the engine, the bad news the amount of work (at $75 per hour!) that would be involved in installing the new engine.   Our options were to dismantle "old Yanny" into pieces small enough to remove from the boat and then break down "new Yanny" the same way, to get it into the engine room.   The cost would be considerable, not to mention the unpopular idea of dismantling a brand new engine prior to installation.    

Our beloved Yanny Senior.

We turned to our old buddy Harry ("the welder") for his advice and finally, together, we came up with a new plan.    A "soft patch" would be created in the cockpit floor above the engine room.  This would mean cutting a hole large enough for the the engines to be craned through and, on completion of the installation, replacing the steel with a new, removable steel hatch in the cockpit.    The cost of this method would be considerably less and installation would be much easier.  Now we had a plan, the new motor was ordered, installation to be carried out by "Team Anju", whose rates were considerably less than the mechanics!   After all, how difficult could it be to replace a motor with one of the same make?    Oh those glorious golden days of naivety! 
We needed to get the old motor out of the engine room as well as the generator, which we were also removing, before the new engine was delivered.  This would allow time for preparation and painting of the hull and floor inside the engine room prior to installation.   

Our first step was to remove the hydraulic steering system from the cockpit, to clear the area ready.  Soon, Phil was on his knees in the cockpit, circular saw in hand, nervously beginning to cut out the soft patch.   It wasn't a nice feeling taking a circular saw to your boat.  However, on the plus side, working in the engine room became much easier on the back muscles when the new sunroof was created and you were able to stand up straight in there!

Cutting a hole in the boat!

With the aid of two "come-alongs", we were ready to haul Yanny out into the cockpit, to await the arrival of the crane, whilst we began preparation of the engine room below.    Harry again came along to help and with much effort and a little ingenuity, the three of us lifted the motor onto the remaining steel beside the new hole in the cockpit.

Phil enjoys the sunroof.

Yanny sees daylight for the first time in over 20 years!

Who is that masked woman?

Christine was let loose in the engine room with angle grinder, sander and degreaser for the unpleasant task of preparing the surface for painting.   Harry welded the lip around the hole, on which the new hatch would rest, before we started painting, to ensure the new paint wouldn't get burnt.   Then, over the next few days, all was painted with several coats of epoxy primer and bilge paint, until the hull looked like new again.

The new engine was due early Tuesday morning and we waited aboard excitedly for its arrival.   By lunchtime there was no sign of truck or engine, so we made enquiries.   Apparently the truck driver had been unable to find the marina and had gone on to his next drop off, way south of us in Palatka.    We were told that he'd try to drop off the engine on his way back that afternoon.  By now we were nervous as the crane was already booked for the next day.   So, we sat and waited expectantly all afternoon.  



By six pm, with no sign of the truck, we had to make a trip to the grocery store to buy something for dinner.     Needless to say, as soon as we'd left the yard, the truck appeared and dropped off our special delivery, so we missed the whole thing!

Next morning, on opening the crate, it looked as though the driver may literally have dropped-off our engine, as the crate was damaged and one engine mount bent.    Fortunately the engine itself seemed undamaged and a new mount was quickly despatched from Yanmar. 


Out with the old.......



By the time the crane team arrived, old Yanny was fitted with chains and ready to lift, Genny, the generator was also waiting in the cockpit to be removed from the boat.    We'd decided that we really didn't need a 6 KW generator.   All we normally ran with the generator was the battery charger and carrying the weight of the big generator around the world with us, just didn't seem justified.   Whilst the crane was available, Genny was to be lifted out, for sale and replacement with a small portable 2KW Honda generator.

In with the new.

Harry supervises the generator lift.

The crane crew were very skilled and despite the complications of working around and above our neighbouring boat and within inches of the radar and wind generator mounted on our mizzen mast, nothing was damaged during the heavy lifting.    In just half and hour the crane work was finished and the new engine stood in the engine room.

New Yanny ready for installation.

The first challenge was to decide on the correct spot on which to locate the new engine.    We drew up the prop shaft towards the gear box to determine whether the position fore and aft was correct.   Here we made the first, of many, many, many discoveries which would necessitate extra work.   The coupling on the new engine was an inch smaller in diameter than that on the prop shaft.    We'd need a new coupling for the prop shaft.   One was duly despatched from Yanmar.    

Meanwhile we had to remove the old coupling from the prop shaft, which proved impossible with the tools we had available. It was firmly stuck, possibly rusted, in place.   Harry came to our aid, manufacturing a coupling puller to fit and, with the aid of the puller, the coupling finally came free from the shaft with an incredible bang.

We tried the new coupling on the shaft, only to discover that our shaft was tapered, apparently with a non-standard taper, whilst the coupling had a straight bore.    After much consideration and inspection of the rest of the prop shaft, our ultimate solution was to replace the entire shaft, which we discovered was badly scored by the stuffing box, with a new standard shaft.    More work, more time, more money.    

Now we needed to remove the stuffing box and propeller, in order to pull out the shaft.   The propeller proved just as stubborn to remove as the coupling.   Prior to ordering the new shaft we decided that, now we had the freedom to determine the desired length of the new shaft, we'd like to move the engine forward a few inches, to create more working room around the gearbox at the back.    

Eventually everything was on its way to Jacksonville Prop for machining of the new shaft.   Of course, on arrival we were informed that our prop also had a non-standard taper bore.    Now we faced another dilemma, if we machined the shaft to fit our existing prop and later discovered on sea trials that we were under-propped with the new engine, we'd have to find a new prop with the same non-standard taper.   With our custom built, one-off steel boat, even the experts didn't seem able to give a definitive prop size for the new engine, so some experimentation would surely be required.  Our new prop shaft was finally delivered with standard propeller taper and the existing prop bored out and fitted with a sleeve, to make it fit.    Now we could finally begin to position and align the new engine.

Our Yanmar mechanic called to check and assured us we'd still have room in front of the engine for the required 3" exhaust muffler for the exhaust system he had in mind.   Whilst he was there, we picked his brain about how he would begin the engine alignment.   Our concern was that with a shaft 8 feet long supported only at the end where the cutlass bearing was located, it would be impossible to ensure that the inch and a quarter shaft was accurately centred in the 3 inch diameter stern tube before beginning alignment.    What was our mechanic's advice.    No problem, we were assured, he would just look down the tube and decide by eye when it was in the centre.    "Uhm, huh?" we thought to ourselves, this didn't seem a very accurate way to begin to align an engine to within a thou of an inch.     This would need a little more thought than the mechanic seemed to believe would be justified.

Phil lay awake and pondered the issue overnight.    Finally he had an idea to manufacture a temporary support bearing to fit the stern tube out of plywood, to assist during initial alignment.   On further consultation with our experienced machinist neighbour, John, together they came up with a design for a support machined from a PVC pipe cap on which, with his specialist lathe equipment, John could machine the inch and a quarter hole for the shaft precisely in the centre.   Next day John returned to the yard with his fabulous invention, now we were getting somewhere. 

On installation of the shaft, we drew the new coupling up towards the gearbox and discovered, as we'd suspected, that the engine would need to be raised up by about one inch.   Four 1" hardwood shims were cut and on placement below the engine mountings, they positioned the engine at more-or-less the correct height to meet the coupling.     With the aid of John, our invaluable neighbour, who had lately also become a fibreglass expert, we decided to epoxy the shims in position prior to drilling the holes through the wood and steel for the engine mounts.   First we'd need to carry out engine alignment to ensure we would epoxy the wood in the correct position.    

Our experience of engine alignment was somewhere between limited and non-existent.   However, with an awful lot of patience, some advice from Harry and John and our trusty feeler-gauges in hand, after about two hours we were almost there.    At this point our mechanic called by to check on us and somehow managed to knock the engine back out of alignment.    We were not impressed as we began the alignment process again.    Finally, once again, we had the correct position and marked the location where we would epoxy the wooden shims.     

Now, of course we had to undo all the good work and lift the engine out of the way to apply the epoxy and place the wood back down in the correct position, to cure overnight.    

John helps us drill the holes

Next day we began all over again to align the engine on the now fixed wooden shims.    This time the alignment would allow us to mark the correct locations of the holes for the bolts which would secure the engine mounts through the wooden shims to the steel engine beds.   Once the spots were marked the engine had to be moved again to allow the drill to reach the right spots.   It was no easy task drilling through the half inch steel engine bed and several drills were harmed in the making of the holes!

A day later and we were ready to position the engine and bolt it down for final alignment.    Now we were becoming experts as we'd already aligned the engine three times before!   The engine was bolted in position but before connecting the prop shaft, we decided to replace our old stuffing box with the new drip-less type of shaft seal, to eliminate salt water and the resulting potential for rust in the bilges.    

The "dripless" seal was delivered and about to be installed when Phil discovered that there was a serious moulding fault on the rubber bellows section, leaving at least two indentations several millimetres deep in the rubber.   If installed this would have left only a couple of millimetres of rubber protecting us from the ingress of the sea.   The manufacturers were contacted and another bellows sent by overnight delivery.   We were a little amazed that the original  bellows would have been despatched seemingly without quality inspection, bearing in mind the critical nature of the seal in stopping the boat from sinking!    We also wondered if a different installation mechanic would have spotted the fault, perhaps installing things yourself was a safer option, even if you lacked experience!

Holey Seal Batman!  Our not so dripless seal!

Finally we were able to put it all together, finish the engine alignment and bolt the shaft to the gearbox.   What a relief!

Now our exhaust system required attention.   It would be a completely new installation as the old exhaust had a 2" diameter whereas the new 54 hp engine needed a 3" diameter exhaust system.    The starting point would be the new exhaust muffler, which was of considerable size to accommodate the volume of water from the 3" diameter exhaust pipes.    We decided to get the muffler first, then work on the rest of the design.   The mechanic had advised us to locate it down in front of the engine and checked to make sure there was plenty of room.   Needless to say, it was delivered and wouldn't fit.    Aargh.     

The mechanic was called in again to view the problem.    In addition we had concerns about the exhaust design he had in mind, as the water would need to lift almost ten feet from the bottom of the muffler to the exhaust outlet and we were worried about the resulting back-pressure.   Everything we'd read advised a maximum lift of four feet, so this too was discussed.    Following discussions we agreed to differ with our mechanic and re-design the exhaust system ourselves.     

During this visit the mechanic also looked over the engine installation and asked where the fuel return lines would run.      This was a new and interesting concept to Team Anju.   Somehow the previous engine had run for twenty-odd years with no fuel return lines to return unburned, excess diesel fuel back to the tanks.   When this was pointed out, it was a bit of a mystery to us how it had worked so well and we were left with yet another job on the ever increasing job list!

New Yanny secured in place and aligned.

Hmm, fuel return lines - interesting concept.

We'd cleared Green Cove Springs and most of Northern Florida out of 5/8" hose fittings in the creation of our new fuel return lines and had to leave the assembly just one hose-barb short.   We were ready for a break and it was time to hit the road to head north by road to North Carolina and Maryland.    We were most definitely ready for a break from the hard work!
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