carb adjustment two Elgin 1.25

[Timothy McDonald]

Thanks dave, It is snug, set it to where i can move it but it’s stiff. don’t want to leak fuel. I’m now puzzled. Two different valves. I’ll get out next time the sun shines and take tools. I’ll switch valves on the lake.

[billw]

Timothy McDonald wrote:

Billw, I took out the valve stems and one from a parts Elgin 1.25. the parts motor has a different valve. Much sharper. Do you happen to know what’s in your motors?

That’s interesting. Now I’m going to have to go take them out and find out!!

Long live American manufacturing!

[frankr]

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[Timothy McDonald]

I was just out on the water with this motor. My take on this is a follows. The sharper valve solves my problem of oversensitivity. Note that valve has no knob, just a small cross pin. I guess the original users finding they could turn the valve all the way in or all the way out managed to either damage the valve or get the adjustment wrong. When they took it back to Sears the company was notified of the problem. As those who know the motor know, I did not mount the carb face plate since it prevents turning the valve more that 180 degrees. On a rebuilt motor and carb you’ll need more motion than that. However, to make the carb fool proof I think the factory came up with the indexed knob which has a lug on the bottom which prevents over 180 degrees motion WHEN the faceplate is mounted. For a new motor the factory simply ran the motor and set the knob. Because there was only 180 degrees movement possible they had to alter the needle vale tip for greater sensitivity. The sharper valve needs near a quarter turn to do what just a sixteenth inch , maybe 5 degrees, will do on the blunted valve. If the motor is new and running new, this works fine. On a worn motor it doesn’t work. I’m quite certain someone removed the faceplate in the past and twisted the valve all the way in , and tight… maybe to prevent leakage when the motor sits in the car. However, I still feel the seat is damaged. With the sharp needle this doesn’t matter. How’s my logic?

[Timothy McDonald]

You can see the stop opposite side of pointer

[Timothy McDonald]

The boat and motor

[frankr]

Timothy McDonald wrote:

I was just out on the water with this motor. My take on this is a follows. The sharper valve solves my problem of oversensitivity. Note that valve has no knob, just a small cross pin. I guess the original users finding they could turn the valve all the way in or all the way out managed to either damage the valve or get the adjustment wrong. When they took it back to Sears the company was notified of the problem. As those who know the motor know, I did not mount the carb face plate since it prevents turning the valve more that 180 degrees. On a rebuilt motor and carb you’ll need more motion than that. However, to make the carb fool proof I think the factory came up with the indexed knob which has a lug on the bottom which prevents over 180 degrees motion WHEN the faceplate is mounted. For a new motor the factory simply ran the motor and set the knob. Because there was only 180 degrees movement possible they had to alter the needle vale tip for greater sensitivity. The sharper valve needs near a quarter turn to do what just a sixteenth inch , maybe 5 degrees, will do on the blunted valve. If the motor is new and running new, this works fine. On a worn motor it doesn’t work. I’m quite certain someone removed the faceplate in the past and twisted the valve all the way in , and tight… maybe to prevent leakage when the motor sits in the car. However, I still feel the seat is damaged. With the sharp needle this doesn’t matter. How’s my logic?

Lots of those Tillotson high speed needles get destroyed by improper removal of the float bowl. Since the needle point is sticking into the seat, just removing the four bowl screws and giving it a whack to remove it—guess what—-you just bent or broke the needle.

[Timothy McDonald]

Thank you frankr. I am fortunate to have a third motor and carb to examine. The extra carb is on the table and you’re right, the needle has to come out first. Using a jeweler’s glass to examine the seat shows it is not in good shape. I don’t know what the carbs on those two engines are like. I just cleaned them and didn’t know what to look for. The seat in this case is just the pot metal casting. The needle tips are smooth metal, steel I presume. However, under the magnifier (25 power) the lathe marks are obvious. The pot metal seats are rough. What I see are two rough surfaces in contact and trying to micro regulate a very small engine. I started this thread hoping to avoid damage. What I will try to do is polish both seat and valve tip.
BTW…those of us with small boats/canoes, have a very limited choice of engines.
more to come…

[Timothy McDonald]

and yes, you are correct, the needle is bent.

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