Please help me fully ID this motor

[colbyt]

I know it was sold by Sears under the Ted Williams name. The ID plate is on the transom mount but only the stamped last 4 digits of the model number are readable. The paint printed portion has faded away. The four digits on the ID plate match the numbers stamped into the engine block (8530).

My understanding is that McCullough (574) made these for Sears from 1959-1969.

Pictures of reputed 1966 models I have found online match this motor except for the gas tank details (covered below).

The engine has a Walbro carb (LMB-131) and those were made for only McCullough outboards. This carb appears to have had a bowl drain valve at one time.

So I have deduced that the Sears model number is 574.?8530.

I think the gas tank detail is the key to narrowing this down to a few years. This is an all metal tank with a twist and lock radiator type cap. The vent (now capped) was a separate thing. I assume some type of petcock. The other detail that is strange to me is there is a place for a radiator type overflow tube at the top of the gas tank fill point.

Not EPA approved I am pretty sure.


I would like to come up with a year and model number.

More important is to determine the proper oil/fuel ratio.

 

[Frank Acampora]

Re: Please help me fully ID this motor

Well, can't help you any further than you have gotten now with the year and model. HOWEVER: The engine is air cooled. Typically air cooled engines in the 1960s did not have roller bearings on the rod big end. Thus you would use a minimum of 25 to 1 fuel to oil and possibly even as much as 12 to 1.

 

[colbyt]

Re: Please help me fully ID this motor

Guys, I just realized a major mistake in my initial post. The 8530 is the the serial number. That is why it is stamped on the block and the tag.

If you can't ID this rascal how about giving me as many model numbers for a 3.5 or 4hp as possible for the 59-60 time period.

I solved my initial problem by using a round lawn boy filter and making an air filter housing from a tuna can; seemed sorta appropriate to me.

 

[belairbrian]

Re: Please help me fully ID this motor

Not sure the filler is really going to help as IMO it is not original but rather a homemade repair.

Maybe a shot in the dark but can you find any parts with a part number stamped on them. Trying the on the sears part website might yield an answer.

 

[nwcove]

Re: Please help me fully ID this motor

i could be wrong, but it also looks as tho it actually is a radiator cap and spout brazed onto the original tank.

 

[colbyt]

Re: Please help me fully ID this motor

Not sure the filler is really going to help as IMO it is not original but rather a homemade repair.

Maybe a shot in the dark but can you find any parts with a part number stamped on them. Trying the on the sears part website might yield an answer.

i could be wrong, but it also looks as tho it actually is a radiator cap and spout brazed onto the original tank.

I think you two guys nailed it. It has been a very long time since I viewed an all metal tank but I suspect the factory weld would be neater, though this one isn't bad. A close examination of the 'vent spout' reveals it to be weld in place also. I am pretty sure a factory one would have been threaded.

The carb is the only part that I have yet discovered with a part number and it is not a Sears number. Walbro made a 131 and a 131A. Determining the change year might narrow it down a little.

So it looks most like a 65 or 66. Anyone got a model number for those years?