Archive for December 29th, 2011

29
Dec
11

Beyond the Sea…horse!: Outboard motor restoration step by step…Day Six!

Ten and one-quarter hours spent working on this little motor so it can run…hopefully…another 50 years.  So far we have torn down the power head, the motor leg, repacked the lower unit, replaced the clutch dog (shift member), stripped all parts and primed and painted them…as well as decaling the hood.  Now the power head is going to be rebuilt and the final assembly of the motor finished.

Let’s get underway!

Power head components....EVERYWHERE!

This piston is pretty scratched from carbon getting stuck in the cylinder between the piston and cylinder wall.

Crankshaft bearings must be looked over with a critical eye. O-rings should always be replaced. These o-rings had given their all a long time ago!

Using a sharpie marker, I like to mark each connecting rod and related cap.

The motor block has been honed and all carbon must be cleaned from the block as well. Leaving excess carbon around cylinders and ports can cause heat issues.

As a matter of routine when a power head is over-hauled, at minimum new (or good) piston rings should be installed, and the cylinders honed to break the "glaze" or smooth surface of the cylinder walls. In this photo you can see the scratches from the honing process.

Used care placing the pistons in the cylinders. You must compress the piston rings so the engage the small dowel in the ring groove into a notch that is cut in the piston ring. Do not force the ring into the cylinder or breakage of the ring may occur.

Using needle bearing grease...or in this case Vaseline...we can now lay the 29 needle bearings into the connecting rods and rod caps. COUNT THEM! These bearings are not caged...there is no cage for the bearings to lay in, so they must be laid in the Vaseline to hold them in place until assembly is complete.

Half of the the needle bearings are in place on the connecting rods.

Once the bearings are install...all 29 of them...you may place the rod caps back on the matched connecting rod. Be sure to torque the connecting rod cap screws to the proper specs.

A low grade lacquer thinner is used to clean grime off all nuts, bolts, and hardware.

All original hardware is cleaned in solvent and readied for installation.

Using a new-old-stock gasket kit the crank case halves are mated beck together using 3M Scotch-grip 847 to seal it. This material is also used on all screw threads.

Final coat of paint has been applied to the lower-unit and transom clamp assembly.

This area was blemished with a drip. It is un-noticable now.

The exhaust leg has been installed prior to installation of the power-head.

Magneto ignitions use magnetic force to derive their power. No batteries needed.

I always clean the magneto plate to make sure it is spotless. This will allow you to quickly see if gasses or oil are coming out of a crankshaft seal later on down the road.

The coils and condensers checked good, so new plug wires were added, and the mag plate cleaned. The magneto is ready for installation.

A front shot showing the shifter and carb. The magneto has been installed.

New ends are attached to the spark plug wires. Neon spark testers are used in-line with the plugs to check for good ignition spark.

The flywheel and recoil have been installed.

The paint on the I.D. tag has faded or flaked off. This needs to be touched up too.

First lightly paint the I.D. tag with paint, then use a razor blade to lightly etch the paint off the raised areas.

With installation of the hood, this old Sea-Horse is ready for action again!

So after an additional two hours we have just under 13 hours of time in to making this old motor ready for action again.  Upon bucket testing and setting the carb jets, she seems ready to run.  Looking forward to spring to let ‘er rip on the river.

 

Hopefully this six part blog will inspire others to take on a challenge and give life to an old outboard motor.  Thanks for reading!

Greg