Tecumseh HMSK80 needs full choke to run


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Old 12-25-09, 04:31 PM
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Tecumseh HMSK80 needs full choke to run

I have an Ariens 824 from 2001 with the Tecumseh HMSK80 spec# 155699W engine. In Apr 2009 I had the carburetor replaced with the Tecumseh 632334A carburetor. The original carburetor surged badly and needed to be repaired or replaced. We had our first big snow storm in eastern Kansas yesterday, and this was my first heavy use of the snow blower with the new carburetor. As the work developed I found that I could not keep the engine at full throttle unless I had it almost fully choked (choke on almost all the way). It seemed at each restarting during the morning I had to use progressively more choke. What is the problem? Can I fix it myself? Thank you.
 
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Old 12-25-09, 04:39 PM
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Shut off the gas or drain the tank. Then remove the bolt on the bottom of the float bowl. DO NOT REMOVE THE BOWL. The bolt has 2 holes in it. The big hole is easy to see. The small hole located 2-3 threads up is just a tiny pinhole. This is the hole everybody misses. This is the hole that needs to be cleaned. Use a small torch tip cleaner or try a paper clip. You may have to soak it for a couple hours to lossen the dirt.
 
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Old 12-25-09, 06:39 PM
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I was looking at a diagram of the Tecumseh 632334A carburetor in Disassembly of Tecumseh (Lauson) Series 3 Carburetor 632334a and it shows the idle fuel transfer port in the bowl nut, but that diagram shows no other hole. I assume what you suggest is take the bowl nut and gasket carefully off leaving the needle screw as it is in the bowl nut. Then is it the idle fuel transfer port that has to be cleaned? Also, when the bowl nut is reinserted, is it just nominally tightened?
 
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Old 12-25-09, 08:50 PM
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The 2001 carb is a fixed jet. No adjustment. The carb in the diagram is a pre 1995 adjustable carb. If you do have the adjustable carb, the hole in pic #6 is the hole to make sure is clean. Lightly seat the screw, then adjust the screw 1-1/2 turns out.
 
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Old 12-27-09, 02:32 PM
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At the time the carburetor replacement was done it was hard to get Tecumseh carburetors. Originally the carburetor was the 640052 nonadjustable, and it was replaced by the 640349 likewise nonadjustable. Someplace in the forums the pre-EPA 632334A was suggested as being available, and if properly adjusted, then it is a very robust carburetor enhancing the HMSK80 performance. Tecumseh had gone bankrupt and OPE users were scrambling to find replacement parts.

After I clean out the idle transfer port as you suggest, is it okay to replace the bowl nut with the original gasket? Then, I presume I have to readjust the main mixture screw and the idle mixture screw. My data shows the main pre-set is 1-1/2 turns out, and the idle pre-set is 1 turn out. From there I have to make the final adjustments.

Excuse the naive questions. The only DIY I usually do is change the oil and spark plug on the snow blower. Thank you.
 
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Old 12-27-09, 05:09 PM
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Originally Posted by Richard904
At the time the carburetor replacement was done it was hard to get Tecumseh carburetors. Originally the carburetor was the 640052 nonadjustable, and it was replaced by the 640349 likewise nonadjustable. Someplace in the forums the pre-EPA 632334A was suggested as being available, and if properly adjusted, then it is a very robust carburetor enhancing the HMSK80 performance. Tecumseh had gone bankrupt and OPE users were scrambling to find replacement parts.

After I clean out the idle transfer port as you suggest, is it okay to replace the bowl nut with the original gasket? Then, I presume I have to readjust the main mixture screw and the idle mixture screw. My data shows the main pre-set is 1-1/2 turns out, and the idle pre-set is 1 turn out. From there I have to make the final adjustments.

Excuse the naive questions. The only DIY I usually do is change the oil and spark plug on the snow blower. Thank you.
Yes, you can reuse the gasket if it looks good, not torn any where. Yes, 1-1/2 tunrs out from lightly seat is the starting adjustment for both low & high speed settings. The screw on the bowl is high speed.
Tecumseh DID NOT go bankrupt. They were bought by investors who were only interested in the Air Conditioning part of the company. They knew nothing about small engines, and with small engines accounting for only 5% of the business, they decided to drop it. They were able to sell Peerless transmisions to Husqvarna. No one was willing to buy the engines.
 
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Old 12-27-09, 06:05 PM
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Originally Posted by indypower1
Yes, you can reuse the gasket if it looks good, not torn any where. Yes, 1-1/2 tunrs out from lightly seat is the starting adjustment for both low & high speed settings. The screw on the bowl is high speed.
Tecumseh DID NOT go bankrupt. They were bought by investors who were only interested in the Air Conditioning part of the company. They knew nothing about small engines, and with small engines accounting for only 5% of the business, they decided to drop it. They were able to sell Peerless transmisions to Husqvarna. No one was willing to buy the engines.
Actually I believe the original tecumseh company continued in the air condtioning compressor business and sold the engine/transaxle business to an Equity group. That group then sold the peerless stuff and quit making engines and then later sold engine parts and engine rights to a parts company.
 
 

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