Archive for December, 2010


Anatomy of a Motor: Mother Nature’s wrath on an old Sea Horse!

This motor has literally been blown…by Mother Nature…in a tornado.  She rode out a tornado on June 5th, 2010 in Monticello, IN when the backshop of Fillinger’s Marine was destroyed by a big ‘un.  That same tornado dropped in on Toledo suburbs in Lake Township, destroying their police station and high school.  Also Milbury, Ohio got hit with the F-5 tornado and it levelled a good portion of the town.  Five souls were taken that night by the storm.

This old Sea Horse was found several hundred feet from where she started her flight at Fillinger’s…in a field…battered and bruised.  Before she was a pretty good specimen of her breed.

I wanted her when I saw her at the AOMC Constantine, MI Super Meet in July, but upon seeing the damage, I was hesitant to pay 75 dollars for her.  Stewart Fillinger, who had used her on his boat as a teen, assured me she would be a good motor, but I declined.  Besides, there was another one like her under the tree for auction later in the day.

When the auction began, Stewart rolled up in his golf cart.  I expressed how much I’d like to have the old SD-15 for my collection.  He suggested I bid on the one at the tree, and if I lost it…we’d let that set the price for his.

The auction began, and quickly the price skyrocketed to 25 BUCKS!  I gave up!

I asked Stewart if he would take less…and true to his word he said “Well, looks like todays market price is 25 bucks.  So 25 bucks will do it”  I was dumbfounded.  He even loaded her up in the truck.

So the restoration began by finding a few spare “parts motors” at the boneyard.

Mother Nature punched this Sea Horse right in the nose. The dent is big enough to put your fist in.

There was a lot of minor damage too. This little chip was missing from the lower unit.


This is a two and one half-gallon fuel tank that wraps around the powerhead. I wasn't sure that this dent would come out, so I got another tank to replace it. Turns out that tank was even worse!

As I got into the project, I thought about the night the storm hit.  I found out that Stewart had been so kind as, when approached about help to clean up what was left of his business, to send those kindly folks to the church next door that had sustained damage too.  This resonated with me.  It kept me thinking.  I knew Stewart only slightly, but what a guy he must be to make a gesture like that.

But like most good outboard technicians, they take care of their own stuff in a much less desireable way than they take care of their customers.  Stewart was no exception.  He had obviously not run this motor for a long while.  The carb had enough varnish in it, and on it to varnish a small sailing craft!

The fuel filter bowl was full of old varnish from ancient fuel being left to die there. The breather was coated as well!

The agonizing process of removing that big dent had to start when I found my replacement tank had more body putty than what I would need to bring the original tank back to specs.  I set about the three or four-hour process of plugging the fuel line fitting holes with rubber stoppers and using compressed air into the tank, in conjunction with a propane torch to heat the heavy aluminum around the outside edge of the dent.  Then by spraying cold water on the aluminum occasionally, the aluminum would contract.  Worm was sped up by lightly tapping around the edge of the dent with a rawhide mallet.  The vibration with the compressed air causes the dent to slowly pop out into its normal shape.

After thoroughly washing the tank out, I closed off all pipe fittings with rubber stoppers and pumped 15lbs of compressed air into the tank. Using a propane torch, the aluminum was heated and cooled (using cold water in a spray bottle) and the majority of the dent was slowly removed.

Tools of the trade. you can substitute dry ice for the cold water. Just heat, then lay the dry ice over the dent. Works very well!

A dent in the side before...and after. Unfortunately, the decals cannot be saved in the kind of work. Too bad!

With most of the dents eliminated, work turned to sanding the tank to give some tooth for the body filler to grab.  I used a base coat of PC-7 two-part filler, then sanded it and used a skim coat of J.B. Weld 5 minute epoxy over the PC-7.  The J.B. Weld has a nice smooth surface.  When sanded there will be enough roughness for primer and paint to grab hold of.

A thick coat of PC-7 was used for the main filler. This can be purchased at you local hardware store.

Other smaller dents looked to be "old damage".More little dings had to be filled!

More little dings had to be filled!

After sanding and sanding, the tank finally looked as though it was saved from the scrap heap and would be placed back on its perch atop the powerhead from whence it came.

With J.B. Weld applied, more sanding...finish sanding will follow.

The dents in the tank are now largely removed or reduced, filled, and ready for finish sanding and primer and paint.

Attention now is going to shift over to the mechanical from the cosmetic.  Compression, spark, and fuel.  Three components that must be had to have a working motor.  This motor has compression…LOTS OF IT!  Spark is non-existent, and we saw the carburetor earlier.  No way that is going to supply good air/fuel mix to the spark when we do get it!  So let’s dig into the carb.

This baby is caked with crud!

The carb must be disassembled completely and cleaned.  All passages must also be cleaned and cleared of any obstructions or dirt and varnish.  The carb is a barrel-type, float feed.  It takes fuel in from the glass fuel filter bowl, through a wire mesh screen which traps dirt, and feeds the fuel to the float bowl by way of air pressure from the fuel tank.  Yes this is a pressurized fuel tank…just like those old OMC suitcase tanks everyone is afraid of!  Pressure is pumped into the tank from the cylinder by way of a check valve on the side of the block.  One the downstroke of the piston, pressure is pushed through the check valve and air is pushed into the tank to force fuel toward the carb.

I digress.

Once the fuel bowl is full a float made of cork rises with the fuel level and closes a needle valve in the bottom of the bowl, thus no more gas is allowed in until the fuel level drops the float, opening the needle valve.  The needle valve is place vertically within the carb bowl.  A check valve with another fine mesh screen is below it.  This MUST be cleaned, as this is where a great deal of sediment gets stuck.

Next the fuel is fed through two needle, a slow and high-speed needle which feeds fuel into the barrel valve that allows the fuel to enter the manifold, and on into the block and cylinders to be burned by our elusive spark.

Carb parts!

I used aerosol carb cleaner to cut the goo in the carb passages and generally clean the parts. Then everything was soaked in lacquer thinner to get the rest of the gunk of each part.After cleaning everything thoroughly, the carb is reassembled and ready for action.

The carb float should be re-sealed.  Back in the good old days, before the government decided ethanol was a grand idea, shellac was used to protect the cork from the gasoline.  Now with ethanol in our fuel, the shellac will likely peel off, so the cork must be protected.  You can use model airplane fuel-proof hot dope, or I use CPES from Smith Brothers.  It is a thinned epoxy that soaks into wood, or this case the cork, and protects it by encapsulating the material it is applied to.
Now lets figure out why we have no spark.  The coils in the magneto ignition of this type are not known to fail, but we have no spark on one of the high tension wires.  First thing to do is completely dissemble the points and clean them to a high luster.

To get to the magneto, you'll have to use a flywheel puller to pull...uh...the flywheel. Mine was purchased at the car parts chain store.

Next we’ll examine and clean the magneto.

Upon checking the coils with a multimeter, one was found to be open. Thus no spark! Having removed it, and taken one from a donor motor, it will be replaced.

The magneto has been rebuilt, the points cleaned and reassembled, new plug wires have been added too. Be careful when soldering the wires to the coil lugs as you can damage the coil windings with too much heat for too long!

When putting new wires on these solder-type coils, you should first tin the wire with solder by stripping the insulation off…then applying solder to the twisted wire.  Then place the tinned wire into the solder lug on the coil…and using just enough heat to do the job, quickly heat the wire/terminal and flow solder onto the lug.  Do not linger long or the small fragile wires inside the coil could be burned open…leaving you back at square one.

Now that we can safely assume we’ll have spark…at least until we reassemble the entire motor…lets go back to cosmetics.

I usually clean and degrease using lacquer thinner or citrus degreaser and water, then soda blast the entire motor while it is still assembled.  All openings at the carb, fuel lines and exhaust are plugged to keep soda out of the motor.

I use a soda blaster from Harbor Freight tools.  It’s cheap, but effective.  However, the soda is not cheap!  two 50lb bags will be used for this project.  Soda, unlike sand blasting, does not harm the soft aluminum.  It also is biodegradable and washes away with water.

After soda blasting, the motor is cleaned and grease seals replaced on the lower unit. Then in preparation for primer and paint, the entire motor must be cleaned with lacquer thinner or a cleaner to get rid of any residual grease.

BASF DP epoxy based primer will be used.  This is a primer and catalyst that is mixed per the instructions.  It must be left to set for 30 minutes to introduce the catalyst into the primer.  This is a good time to get moisture out of your air lines, check the gun…in this case HVLP from Harbor Freight…and check you pressure at the compressor.

After priming and painting the motor…as an entire unit…as much as is possible, the carb is place back on the powerhead.  Also I was able to locate a new-old-stock tiller/throttle handle for this motor from Sea-Way Marine in Seattle.  So it has been put in place as well.

Our nice shiny carb is bolted back in place.

Repainted and nearing completion, with the flywheel and magneto back on the motor, now is a good time to check for spark.

I decided checking for spark was a good thing to do now, before putting the fuel tank on the motor.  Using a pull-rope and spark checker grounded to the motor block, each cylinder was checked.  The spark was nice and hot, and blue.  It should jump a 1/4 inch gap.  You should be able to hear the snap of the spark too.

Now with the mounting of the tank, belly pan and decal, this old Sea Horse looks grand again!

The decals are from American Outboard and Salvage.

What great lines and form these old motors have. It's called "STYLE"!

On the cart waiting for spring.


I would like to mention that since my test tank is frozen, I was only able to test the motor for a second…ONLY because it does not have an impeller water pump.  Doing this to any motor with a water pump will burn the impeller up in seconds with no water to lubricate it.  This motor having no impeller still should not be run out of water…BUT…when the recoil was pulled…she fired right up…LOUD AND PROUD!

It’s December…and now I can’t wait until spring.  However, this motor will not stay with me.  She will go back to a good home…in Indiana…where she was kicked around by Mother Nature.  She will go back to a good-hearted man who helped his neighbors, despite facing challenges of his own following a destructive force such as a tornado.  I will present it to him in January at an outboard meet held at his newly rebuilt marine dealership in Monticello, Indiana.  25.00 well spent.  And maybe a little more.