Sunday, April 27, 2014

Remove the Powerhead on the Flying Scott

Last year I broke a bolt removing it to replace the bracket holding the spark plug wires. The result was a little water leak that I patched externally (so of) with silicon. I decided to fix it right but I need to remove the power head to get to the 3 bottom bolts of the side cover.

The Scott Service manual says:
  1. Remove the hood, then remove the screws that secure the powerhead to the adapter plate.
  2. Disconnect the Fuel Line, battery and junction box leads from the powerhead.
  3. Lift the powerhead assemble off the drive shaft.
The Flying Scott powerhead has thirteen bolts that hold it to the motor plate. Mine had two regular 3/8" hex head bolts with 11 allen head bolts. As you can see this was serviceable with the motor still hung on the transom. I used a ball end hex wrench to access the 11 allen-head bolts. The regualar bolts were removed with a 3/8" open end wrench. On the starboard side it required a socket with a cut off 3/8" drive as a mini-extension to get to the bolt. I was able to turn the square extension with the open end wrench.

The Scott Service manual should have said:
  1. Remove the hood, then remove the screws that secure the powerhead to the adapter plate.
  2. Disconnect the Fuel Line, battery and junction box leads from the powerhead.
  3. Remove the starter, solenoid, rectifier, carburators, caburator linkage, distributor, flywheel and charging system to significantly reduce the weight of the powerhead assembly.
  4. Lift the powerhead assemble off the drive shaft.
After disconnecting the battery cables, throttle cable, fuel line and electrical harness and removing the 13 bolts I removed the powerhead. It was heavy, it's not a one man job. In order to do this alone with no motor hoist, I tipped the motor to the up position and got in the back of the boat. From here I was able to lift the power head off the prop shaft. Then I sat the motor on a table with wood boxes that was the same height as the boat and then I hobbled out of the boat.

I next removed the lower cowl (just four nuts) and stuffed a rag in the lower to proceed with the degrease clean-up of 50 years of grime.

I removed the side cover of the powerhead and had two broken bolts to replace. The bolts were so soft I was able to drill the middle of the bolts and retap the hole to the original 1/4-20 size. Note the salt, compliments of the Pacific ocean. I always flush the motor after running it but salt residue remains!

After cleaning the inside and sealing up the motor. I thoroughly degreased and cleaned the motor. Then I gave it a fresh coat of red engine paint. Autozone calls this Chevrolet Orange Red.

I reassembled the motor with new stainless hardware from Lowes and gaskets from laingsoutboards.com. The side cover uses two gaskets, and there is one at the base of the motor where it sits on the motor plate.

Putting the motor back in without the accessories was much easier. Holding the motor, I stepped up on a sturdy chair and was able to easily put the motor back in place. Check out how nice and clean the lower cowl area is now!

Here's the motor with all the parts back in place and reassembled.

The side cover gaskets are sandwiched with an aluminum plate. This plate allows water to flow around the exhaust port and into the spaces cast into the walls of the motor.


If you look close you can see my modification:


For the bottom 3 bolts I cut off 3 1-1/4" long 1/4-20 bolts and red Loctited them into the case. Then I used 3 nuts with lock washers to hold on the cover. This way in the future I should be able to remove the exhaust cover without having to remove the powerhead.