# Tecumseh AH520 1450A part inquiry



## Ned120 (Nov 14, 2009)

This is a 2hsp. 2 cycle that came with the Toro Snow Husky ( longer rotary blades than on Snow Pup). I need the part no. for the diaphragm in the carb. Was sold a Tecumseh part 630932A diaphragm but it is not pumping gas for me. Was also sold a 630978 which I've not tried as it looked les similar to the original. Rest of carb is clean and seems in good order. Motor runs if I simply put a little gas down in the crank. 
Also need to know the gas/oil ratio. Am using 1/24 as a cautious approach. Motor only running a few seconds. thanks


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## 30yearTech (Sep 14, 2006)

The type of carburetor on your engine is generally a gravity feed type carburetor. 

Did you replace the inlet metering needle and seat? If not, then that may be the problem, at the very least, unscrew the needle and seat and make sure it's clean and open to the fuel inlet on the carburetor.


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## Ned120 (Nov 14, 2009)

It is a gravity feed carb, Larson Power Products 158 6H18, the metering needle has a conical face that does not go below the bottom of the seat. It appears to rely on a pulse action from the diaphragm to lift the needle. It is held in the closed position by a small spring. Appears to be free and clear. A replacement needle and seat I was sold had a pin at the bottom of the needle that did protrude below the seat face, This seems to have produced a constant flooding/over-rich condition that prevented starting altogether. I am back to using the original seat and needle. Am puzzled but stubborn. Thanks for thinking about this issue.


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## Ned120 (Nov 14, 2009)

Have the motor running pretty well. Sourced a Tacumseh tech manual I'll put a link to later. Issue appears to have been the metering needle not being correct and my understanding of the gasket and diaphragm arrangement. A prior owner replaced the metering needle with a too short version that did not allow contact of the needle with the diaphragm. Correct needle has a pin that protrudes through the intake jet. The diaphragm gasket goes on either side of the diaphragm depending on engine type. The manual I'll link to later has the correct interpretation of which engines take which application. Once the correct needle was in and the diaphragm correctly spaced, it started right up and is tunable.


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## 30yearTech (Sep 14, 2006)

Glad to hear you got it figured out. Sorry but I was out of town with no internet for the past week, so I could not tell you about how the metering needle on these carburetor works. Service manuals can be a great help.


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## Ned120 (Nov 14, 2009)

Thanks 30. It's a pretty little engine and now I'm praying for snow to see what it can do. I've got another oddball motor coming up on my next post. Stay tuned.


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## Lawnmowertech (Nov 12, 2008)

Ned120 said:


> Thanks 30. It's a pretty little engine and now I'm praying for snow to see what it can do. I've got another oddball motor coming up on my next post. Stay tuned.


ned in your prayers can you fit me in them here is the situation my dad is not got much more time left on earth he is dieing from lung cancer heart problem etc. and could not happen any other time but during Christmas please keep me and my family in prayer 

thank you 
calvin


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## Ned120 (Nov 14, 2009)

Calvin, 
Sorry to hear of your dad's situation. He had many great moments and that is what I'd focus on. No one is gone. My dad passed this year, we still chat in a sense, he'll be right there if in need. - ned


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