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The Snow Man
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Hello all! Nice little forum you have here. Hope ya can help..

Backgound: This engine has about 700 miles on it. Compresion test shows 110 on one side and 112 on the other. I stripped the carb down, soaked and cleaned it out well, however I did not have a new needle or diaphram, just gaskets when I put it back together. I set the carb up 1-1/2 turns on both the high and low. New plugs, have great spark.

The problem: Just doesn't want to start cold. If it doesn't start on the first pull it will not start at all. The plugs get soaked and it floods so easy. If I can get lucky enough to get it running on the first pull and keep it running its fine untill I let it cool down. Then its the same all over again. After about 10 pulls I can see some fuel leaking out the exhaust where one of the joints isn't real tight. What causes this? Something to do with a diaphram or needle?? Just seems like way too much fuel going into the engine to me. The only other thing I can think of is there is not check valve on the return line. Could it be sucking feul through there?? I can't even hit the primer to get it started or it will flood for the first pull.

I have been trying to find a place to order a complete carb kit for a Tillotson but have not found anywhere yet. Is there a place to order online?? Thanks for the help..

-Fess
 

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That should do the trick. Just keep an eye on which diaphram you put where and pay attention to the way they are when you pull the carb apart. Those Tillotson HR and HD carbs have a built in fuel pump, and if they aren't properly assembled, they cause problems, hopefully you have a later model with a fuel return. Those are much better than the earlier ones. You are right on with the screw adjustments, but......this is just to fire it off. Once you get it warmed up, adjust your low speed screw, it should have an L stamped in the casting, most likely in a little, to get the best idle and throttle response off the bat. You may have to go out more with it, but I doubt that. Once you set your low speed screw, it is time for the high speed screw, H on the body casting. Simply block up your machine, and hold it open while adjusting the high speed, usually in, to the highest rpm, then back it out a quarter turn. No more than a few seconds at a time on the throttle though. Recheck your low speed, then high speed, and readjust low, then high, if you need to. As long as the carb is ok, and no dirt is involved, this should set you up for quite a while.
 

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ive had the same problems with flooding, but i know how to adjust this carb ( HD78A), it will flood at the factory settings ( 1 turn out both needles) it will still flood at 3/4 turn out, i runs well but much leaner than the factory says to
( scorpion 340 whip), anyhow runs great, but can u explain this?


ty rep
 
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