Atomic 4 to BETA Marine Diesel

Ian Elliott, Sanctuary, #377


 
Firstly, this is quite a bit of work.  If you have no patience and you have got a spare $3000 extra laying around, get someone else to do it!  However, assuming you do not have the spare green stuff and you are prepared to learn a little patience, proceed as follows.  Order the new BETA engine with Atomic 4 replacement engine mounts, your choice of engine control panel, and a 1 ½” exhaust.  I got the best price from Frank Zerick of Marine Diesel Repower in Yorktown, VA (web site http://www.marinediesel.net) or from Stan Feigenbaum at BETA Marine in Arapahoe in North Carolina.
Removal of Atomic 4
  1) Remove all heavy peripheral items, i.e. the starter motor, the dynamo/alternator, the exhaust manifold complete with carburetor, remove all electrical connections, and oil pressure gauge pipe.
2) Remove sea water pump to enable access to rear starboard engine mount
3) Mine is a west coast boat so has glassed in oak engine beds.  The engine mount bolts were bronze lag bolts with washers and nuts.  The sea water pump hides the rear starboard bolt and the starter motor hides the front starboard bolt so both these items must be removed.  Port side bolts are fully accessible.
4) Use a reciprocating saw with metal blade to cut through the 3 bolts holding the prop shaft half coupling to the flexible drive coupling.
5) Undo all 4 engine mount bolts.
6) Re-mount the bracket for the gear change linkage to the center of the cylinder head and shackle or bolt the lifting chain to it
7) Using a hoist (I used the day sailor’s boat hoist in my marina), lift the engine out of the boat.
8) Using a reciprocating saw, cut the prop shaft coupling lengthwise down to the prop shaft.  Using a large screwdriver and a hammer, split the coupling in half (it is cast so will break fairly easily)
9) Install a pipe clamp temporarily to the prop shaft to ensure that it will not slide back down the packing gland and fall out of the boat (if this happens you will need more than a new engine!)
10) Remove the old exhaust system
The boat will probably have a “bow down” attitude as you have now removed almost 400 lb. of weight from the rear of the boat.
Preparing For New Engine
  1) If you have a fiberglass tank, use a 4” hole saw to cut an inspection hatch in the front of the tank so that you can thoroughly clean the tank inside.  (To minimize risk of fuel vapor ignition, drain the tank as much as possible prior to this and use a battery powered drill motor for the hole saw).  If you have access to a lathe, the cover for the inspection hatch can be made fairly easily out of aluminum and neoprene or treated gasket material.  For those with a fiberglass tank, the wall thickness is 3/8” so you can drill 8 to 10 holes around the 4” hole, tap the holes and fix the inspection plate on that way.  If not, be prepared to spend $100 on one from a chandlery (if you want to know how to make one, use one at the chandlery as an example)
2) Thoroughly clean the inside of the tank.  If you want to see inside the tank, try not to use a match for light.  If you need a smoke, go away from the boat.
3) Install a bulkhead fitting through the tank for a 5/16” NPT hose barb; this will be the diesel fuel injector return line.  If you have a fiberglass tank you can drill and tap for the fitting.  If you cannot install a bulkhead fitting to the tank, the fuel return can go back to the main fuel filler pipe but you have to figure out how to tee a 5/16” pipe into a much larger pipe.
4) With very careful preparation mark out the new engine mounting holes and drill the engine beds (check twice, cut once!).  You can use lag bolts for engine mounting bolts but lag studs are probably better.
5) Install an Air Lock for the engine cooling water engine to exhaust; I used a Vetus and I installed it as high as possible on to the back of my instrument panel above the engine.
6) Install the engine Control Panel.  I installed mine on the vertical part of the bridge deck so that the back of it goes close to the instrument panel but it can be installed anywhere that is convenient.
7) Clean the prop shaft using emery paper for a good fit for the shaft half coupling.  Use Never Seez compound before slipping it on.  It needs to be a good sliding fit but no real slop.
8) Using a hole saw, install two 4” access hatches into the cockpit floor.  There should be enough room between the fuel tank and the upright of the bridge deck.  The two deck access hatches give you the ability to get to the engine coupling, stuffing box, exhaust etc. and having two means that you can put both hands down there together.  They are cheap and effective.

Installing Engine

  1) Crane the engine into the boat, (I used the marina’s day sailor’s boat crane) and bolt it down to the beds.
2) Slip the flexible coupling in between the engine half coupling and the prop shaft coupling and bolt on to engine.  Now you are ready to align the engine to the prop shaft.
3) Install a new water strainer to the starboard side and plumb up to the engine pump, ¾” hose.
4) Install a water/fuel separator and filter combination to the starboard side and flex to the engine fuel pump.
5) Connect fuel return line from the engine to your new tank bulkhead fitting.

Aligning Engine

1) The more time you spend making this next step correct, the smoother the engine/transmission will be and the less damage will occur to the cutlass bearing.  After “roughing” in, use feeler gauges to measure the gap between the engine output flange and the end of one of the coupling bolts.   Do this for positions at 12 o/clock, 3 o/clock, 6 o/clock, and 9 o/clock.  Get someone else to adjust the engine mounting heights and positions so that the gap is within 0.005” tolerance at all positions.  This is a 2 handed tedious job and a pain in the “neck” but worth it!

Exhaust

  1) I used a waterlock muffler made by Vetus and am very pleased with it, primarily because it installs very nicely underneath the engine.  On a Triton it jams (fits!!) between the 2 sides of the hull into the correct position!  You can get 1 ½” or 2” to suit the engine (I strongly recommend the 1 ½” because the pipe bends easier).  Install a 90 degree fiberglass 1 ½” elbow and some pipe to make the connection between the engine and the Vetus.  The exhaust hose will fit nicely through the cut out in the engine bed that was for the Atomic 4  hand oil pump and connect directly to the swiveling inlet of the Vetus.  Install 1 5/8” exhaust pipe from the outlet of the Vetus (just cinch it down tight onto the     1 ½” outlet) bend it around the front of the engine bed on the port side and let it go to the stern exhaust fitting.  If the old Atomic 4 flexible exhaust is still in place, it should be 1 5/8” so just join them together.
2) Use ¾” hose from the engine outlet to the air lock and back to the exhaust.

Electrical

1) The engine comes complete with a pre-wired harness so all you have to do is plug the engine into the harness of the control panel.  Unfortunately it is 10 feet long so you have to “loose” the 10 feet somewhere.
2) Connect the output of your battery switch to the starter motor and the negative of the battery to the engine somewhere.  Wire the return wire from your other electrical systems back to the engine, giving the other systems a path back to the battery negative.

Starting

1) Put diesel into the tank (a new medium!!)
2) Put a long piece of pipe on to the outlet of the fuel filter and suck the diesel into the filter (if you suck too hard, the “new medium” will get you a new experience!).  Connect the filter to the engine.  Undo the bleed valve on the engine and operate the engine fuel pump by hand until all air bubbles are gone (have lots of rag handy to catch all the diesel, you don’t want it in the bilges).
3) Stick the key into the appropriate hole and wait for the sweet sound of your new engine.

Project Complete