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Installed NOS cylinder,piston and rings(3). New case gaskets and crank seals, also new reed, needle valve and seat, carb gasket. New coil, points and condenser. Motor has brass bushings not needle bearings on crankshaft, no noticeable play in crank. Cylinder prep was light hone to clean wall. Ring end gaps are .015, staggered and on solid material not on any ports. Problem is I get only 60lbs. of compression, this seems to be the starting problem. I have spark and see gas movement in throttle body when priming. Sometimes I had it started but most times it won't start. Tried starting fluid in cylinder and it won't fire. Checked plug many times and it has continual fire. Timing is set by flywheel key(new key and flyweight). Seems to me 60lbs. is no good, specs call for 70 to 85 lbs. Am I overlooking something ?
 

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The compression is good, it may increase as the rings wear in after some hours of running. Timing is set by the breaker point gap, which for this engine is .016. Because this is a snow blower the engine is set to run at 4000 rpm which is controlled by the blue governor spring. Is the governor set correctly? Also you have high and low needles on the carburetor which are a little harder to set than the single needle carburetor. You can find a lot of information here:

 

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The compression is good, it may increase as the rings wear in after some hours of running. Timing is set by the breaker point gap, which for this engine is .016. Because this is a snow blower the engine is set to run at 4000 rpm which is controlled by the blue governor spring. Is the governor set correctly? Also you have high and low needles on the carburetor which are a little harder to set than the single needle carburetor. You can find a lot of information here:

Thanks for the info. I am working on a Snowboy model 1818. I will try setting points at .016. As far as the mechanics manual says I have the governor set correctly. My governor spring is natural color(bare metal) but much taller than the yellow and green springs. I don't have a blue but will try and get one , I did know the rpms were to be 4000. Also I refer to that manual you mention. As far as the carb needles I have the low idle at 1 turn out and the high at 2 turns out.
 

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Cylinder compression and spark is good , but your not getting it to pop when fuel is sprayed directly into the cylinder. Almost sounds like it has to be a timing issue. Spark advance cam worn, or might be 180 degrees out. The points not adjusted properly, and/or upper crank bushings worn beyond limits, which will make points adjustment nearly impossible.


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Discussion Starter #5 (Edited by Moderator)
Cylinder compression and spark is good , but your not getting it to pop when fuel is sprayed directly into the cylinder. Almost sounds like it has to be a timing issue. Spark advance cam worn, or might be 180 degrees out. The points not adjusted properly, and/or upper crank bushings worn beyond limits, which will make points adjustment nearly impossible.








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Thanks for the input. Spark advance cam seems good and tight to the crankshaft, I don't see any wear at the points contact on cam. Crankshaft upper and lower bushings don't have any noticable play. The flyweight (spark advance) is on correctly. The points were set at .020, will reset them to .016 as suggested in earlier response, see if that helps. Again thanks for your thoughts. Ed
 

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Thanks for the input. Spark advance cam seems good and tight to the crankshaft, I don't see any wear at the points contact on cam. Crankshaft upper and lower bushings don't have any noticable play. The flyweight (spark advance) is on correctly. The points were set at .020, will reset them to .016 as suggested in earlier response, see if that helps. Again thanks for your thoughts. Ed
Thanks for the input. Spark advance cam seems good and tight to the crankshaft, I don't see any wear at the points contact on cam. Crankshaft upper and lower bushings don't have any noticable play. The flyweight (spark advance) is on correctly. The points were set at .020, will reset them to .016 as suggested in earlier response, see if that helps. Again thanks for your thoughts. Ed
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I have it running now. I did reset points to .016. Also located a new carb primer rebuild kit, it seems to be supplying more gas now. It started on first pull. Thanks for your help ! Ed
 

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Good to hear you have it running. Those old D-400 series primers are notorious for losing the seal. When you push down the primer on those, the seal drops down allowing some fuel to enter. Them when the primer is released the seal picks up the fuel charge feeding it into the venturi. If that tiny seal is bad, not enough of the fuel will be lifted into the carb with the priming action. Also for informational purposes a bad seal on those primers can also cause rough running as well as extra fuel will be pulled from the bowl past the primer creating a rich situation. Bill
 

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Good to hear you have it running. Those old D-400 series primers are notorious for losing the seal. When you push down the primer on those, the seal drops down allowing some fuel to enter. Them when the primer is released the seal picks up the fuel charge feeding it into the venturi. If that tiny seal is bad, not enough of the fuel will be lifted into the carb with the priming action. Also for informational purposes a bad seal on those primers can also cause rough running as well as extra fuel will be pulled from the bowl past the primer creating a rich situation. Bill
Thanks for the info. Ed
 
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