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chrisdm8

Tuning Tips

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chrisdm8
Hello, It's been a while since I posted ... it's been pretty busy around here. We found our recently that my wife is pregnant with our first so preparing for that has taken a lot of my free time. Lots of home repairs to make getting our 100+ yr old house ready for a new born. I did manage to sneak out to the barn this weekend. I replaced a leaky shut-off valve on the gas line of my HB112 and the fuel line while I was at it. Suddenly the engine is actually getting enough gas to run right (amazing) so I re-adjusted the carb. Set it 1 1/2 turns and went from there until it was running well enough. My method for tuning was to get it idling right while sitting there, then try to throttle it up ... adjust again... then try to move ... adjust again ... then try to drive around a bit ... adjust again... then try to drive with the mower deck on ... adjust again ... then try to mow.... adjust again ... etc etc. Finally, I mowed the yard this afternoon and it did fine. I'm wondering if anyone has a better method for tuning carbs. I hate to say it but this is the first time I've had to adjust carbs as all my cars have been FI (I know it's showing my age). So I'm sure someone out there has a better method for tuning carbs. Also, I feel like I got it adjusted "well enough" but of course that's not good enough... I want to get it running "just right" and without all the modern diagnostic tools I'm a little lost. Is there a way to check your tuning by something other than "feeling"? (eg. exhaust gas temps, etc). Thanks!!

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chrisdm8
Thanks! That does help... it should take out a few iterations of trial and error but I guess I'm wondering if there is a more objective way of tuning these engines. It still feels like it's tuning based on feeling rather than numbers. I suppose that's as accurate as you need ... just curious if there is something better.

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Simplicity314
Let it get to operating temp. first. There is no use in adjusting while it's cold then readjusting after it gets warm--useless step since it will run differently when warm anyway. That's what chokes are for--keeping it up and running until it gets warm and smooths out. Congratulations on the pregnancy! You are smart taking care of your tractors before it comes along. It's going to be hard finding time for anything the wife doesn't think is important--even if it is important. Trust me.

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