Robert Paxton McCulloch

Anybody wanna go fast? McCulloch was a racer at heart and the Flying Scott was the last in the line of his go fast goodies. This is an excerpt from hemmings.com on Robert Paxton McCulloch:

In 1946, McCulloch moved his company to California, changed its name to McCulloch Motors, and changed its focus to lightweight two-cycle chainsaws. He did some development work for Kaiser-Frazer at the time, but didn't return to the automotive field until 1953, when he launched the VS57 supercharger, the result of those earlier patents. As with his earlier supercharger, the VS57 initially was produced in kit form for Fords, but soon was available for a wide range of cars and engines.

Kaiser became the first manufacturer to install the VS57 on its cars from the factory, starting with the 1954 Manhattan. Studebaker followed on the Golden Hawk and on the Packard Clipper in 1957, the same year Ford famously offered the supercharger as an option on the Thunderbird.

By then, McCulloch had set up a separate division within the company to produce the superchargers under the Paxton name. McCulloch also had developed two other superchargers: One, used on the Novi cars at Indianapolis, helped their V-8s produce 650hp. The other, the VR57, used a variable ratio and featured numerous improvements over the VS57, not the least of which was the use of engine oil to cool and lubricate the supercharger.

In 1958, McCulloch sold the Paxton division to Andy Granatelli, again changed the name of his company (to McCulloch Corporation), and changed focus once more--to outboard motors. To test those motors, he bought 26 acres at Lake Havasu in Arizona, where he eventually founded Lake Havasu City.

Paxton was again vaulted into the automotive limelight when Carroll Shelby teamed up with the company on a blown 1965 289 Shelby Mustang. The Paxton supercharger option was produced in limited quantities for the Shelby GT-350 Mustang, from 1966 to 1968. This set-up was also available as an over-the counter dealer installed option on standard small-block V8 Mustangs from 1965-‘72.

Watch out for the 75HP Head Gasket!

Previously UN-beknownst to me but the 60HP power head gasket and 75HP power head gasket are different. The Only difference is the location of the cooling hole that allows the water to circulate up into the motor. Imagine my surprise and chagrin when I fired up the Scott and the motor started overheating.

After a complete re-tear down, I found the culprit. Here is the the 75 HP gasket on my 60Hp base see the hole location in the gasket? The second pic shows the base.

 I ordered a new gasket and they were kind enough to verify I got the correct one this time!

Since I had the motor off I also changed the lower main seal. Mine had a chunk missing. (in the pic below right upper). Laings Outboards had one in stock that was a functional replacement.

The cap is held on with 4 bolts and is fitted into a machined area of the block. It has a small rubber ring to seal it. To remove the cap, remove the bolts and tap the cap to rotate it in the machined area. Then you will expose the bolt holes and you can use a dental pick to lift the cap a little bit at a time. I worked my way around 3 or 4 times lifting a fraction of an inch at a time. Once it's lifted a 1/4" you can gently pry it out.

The new main seal (in the pic above on the right lower) just presses into the cap. Then you can reassemble it and go boating!

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.

How Soft is an Aluminum Motor?

One of the downsides to an aluminum block is the motor is fairly soft and it caution is not exercised you can easily strip bolts in the motor. Over the years this has manifested its self on our Flying Scott on the two top starter mounting bolts.

For our motor, the starter has always been an issue and I'm not sure if the bolts were stripped before I got the motor or if they were stripped by Action boat when they "worked" on the starter or if I stripped them in one of my many R&Rs of the starter.

The solution to this problem was to install a set of Time-Serts. These hardened steel sleeves are an ideal fix and actually result in a higher pull resistance than the original aluminum block. The Time-Serts for this job are the 5/16-18. This allows you to use the original size starter bolts. They are sold in a kit with 5 Serts, the drill, tap, counter bore and installation bit.

Installation was very easy, if fact a little too easy. The aluminum is so soft the drill cleaned out the old threads in seconds and the tap, which is usually the hard part, was easily turned with a tap wrench after lubricating the hole with WD-40. The tap turned into the hole with little resistance and cut beautiful new threads. The counter bore created a nice indent for the Sert and the final step was to screw in the Sert with the supplied driver tool. In under 10 minutes the motor was ready have the starter remounted.

My observation is that the Aluminum is really soft so I need to take extreme care in not over tightening any of the bolts/screws in the block. The good news is the Sert completely eliminates the need for the starter bolt to come in contact with the aluminum on future R&Rs. Now I have a nice strong attachment point for the starter.

Paint it Red

This 1960 McCulloch ad features the Flying Scott with the lower cowl painted in Red. I'm thinking about repainting my motor... maybe it needs a little dash of "hot sauce"?

In other random notes... I need to find one of these Scott McCulloch Outboard dealer signs for my garage.

This one is in the Mikkelson Collection and the image is from woodyboater.com. Got one you need to get rid of... E-mail me.

McCulloch Outboard Motors Styled by Raymond Loewy

The Raymond Loewy connection to the Dorsett is well documented in Dorsett sales literature and supported by the cool dash plaque on our Dorsett Belmont. In this McCulloch ad from 1957 the Royal Scotts (40hp) are spotlighted as also being a Raymond Loewy design. While the 60 h.p. Flying Scott is not attributed to Lowey, it's design is consistent with the sleek lines of the Royal Scott.

This article from Outboard Boating 1958 also indicates that the McCulloch outboard motors received their unique styling from the same famed industrial designer.

Some time ago the controlling interest in the Scott Atwater Manufacturing Company was bought by the McCulloch Motors Corporation, one of the country's largest manufacturers of chain saws. McCulloch already had a well-established two-cycle motor experimental engineering department. Within a year of gaining control of Scott-Atwater. McCulloch's experimental facilities plus a generous experimental budget began to generate some changes. The first evidence of the new policy was apparent when in 1957 the Scotts were regarbed in colorful, sleek and sprightly cowlings created by noted industrial designer Raymond Loewy.

Read the full article from Outboard Boating 1958

Google books also returns quite a few results with Loewy and McCulloch mentioned including a McCulloch review in The Fisherman, Volume 9 also published in 1958 where they mention the McCulloch outboards are “smartly styled in the Raymond Loewy Associates’ latest designs”.

 

If you don't know who Raymond Loewy is... his most famous “boat motor” was the Coca-Cola Dole Deluxe... read this article Raymond Loewy: the man who designed everything from the Verge.

Go Big or Go Home

Am I Having Starter Problems Again?
I decided to do a mid-winter start up to run and flush the motor and found I have another starting/starter problem. This was the original issue when I bought the boat and it took me a full season and 3 starters, new battery cables, new dual batteries and a new starter solenoid to sort out. Here we go again...

Since dry-docking the boat in September, I have kept both the batteries on trickle chargers to keep them fresh. But when I went to start the motor both fully charged batteries were unable to turn the motor. The starter was able to rotate the motor about 1/4 of a turn and stopped. When I removed the plugs the motor would turn freely. But the batteries could not turn-over the motor!

The Starter Isn't Getting Enough Amps
Wondering if I might have a bad cell in a battery, I took my Jump Starter/Charging station and dialed it to 40 Amps and connected it to the #1 battery. I was still unable to turn the motor. Next I took the Jump Starter/Charging station and connected the positive clamp to the starter relay and connected the negative clamp to the starter body. (These are the two positions the battery cables connect to the motor.) Essentially I by-passed the battery cables. Then I turned the key and the starter spun the motor robustly and the motor roared to life!

One of the symptoms I've had is the starter getting very hot. I'm told this is a result of the starter not getting enough Amps so the loss of amperage in the cables would make sense.

Here are my old battery cables. They were made from a #6 gauge jumper cable with crimped-on auto-parts store ends. (Its the orange and black cable, ignore the arrow it is pointing to cotter pins.)

Go Big on the Battery Cables
I decided it was time to upgrade the battery cables. Originally I had made a set of cables using a set of #6 gauge battery jumper cable purchased from the local car parts store. I cut the clamps off and crimped on bronze battery cable ends. Since I am running a pair of marine starting batteries I should have 2000 cranking Amps and this should be plenty to turn this starter/motor. I did some research and found there are several factors including the diameter of the cable, length of the cable and the quality of the connections that work against long battery cables. I have all three going against me.

I found a website that recommended to get 100 Amps through a 15' cable you need at least a 1/0 gauge cable. Not 6, not 4, not 2, not 1 gauge... 1/0! And they suggested 2/0 to be safe. I found a seller on E-bay that makes custom marine quality cables and ordered a pair of 2/0 cables for just shy of $185. They called and warned me these cables are 5/8" diameter each. When the cables arrived they were impressive (and heavy). I worried I wouldn't be able to run them around the motor under the cowl.

The Installation
I spent the better part of a day re-running the cables and neatly attaching them to my batteries and to the starter solenoid and starter. Guess what? I turned the key, the starter spun the motor and she fired right up!. The moral to this story... a #6 battery cable is like a straw and two 1000 Amp batteries are like a fire hydrant. The 2/0 cables are likely over kill but they are more like the fire hose I needed.

The battery cables on my 15' boat are 15' feet long! The positive cable starts a couple feet from the stern on the port side of the boat at the battery on/off switch. The negative cable is on a ground buss on the back side of the board where the on/off switch is mounted.

 

The battery cables go back to the stern and across the transom and they are attached on the starboard side of the boat where they then pass through the cable hole in the splash well.

From the cable hole they they continue back to the middle of the boat along with the fuel line, electrical harness along with the steering and throttle control cables.

They pass into the motor housing along with the fuel line and then around the front of the motor and down the starboard side of the motor.

 

The negative cable runs under the starter is grounded to the motor at the starter bracket.

 The positive cable goes all the way back and is attached to the rear side of the starter solenoid. 

In all that's a 15' journey for the amps to travel.