I always recommend the MTFCA "how to" books on the engine, electrical system, axles, etc., because they are so full of good information. This picture is a little out of focus, but I think it shows pretty well why new drivers are always cautioned against turning the spray needle down too tight. You can spend ten bucks for a new needle, plus shipping that makes it closer to fifteen, or you can take this handy hint from the carburetor book by Hugo Richter:
http://www.youtube.com/watch?v=uTiStUTU9IE
Handy tip, Steve!
I have not looked, but I am probably guilty of turning mine in too hard.
Slick method to save money and an original part!.
Roar
Steve : how many degrees is a spray needle Thanks.
Toon
Steve,
Seeing your video makes the procedure more understandable.-Howard
PS You have a neat looking house!
I must confess that I didn't measure the angle. I just laid a straight edge along the side of the point and marked a line to cut. Measuring the angle of the block with a protractor I get 15º, so the angle of the point would be 30º.
Howard, my grandpa built it after the old house burned down in 1917. Rebuilding the roof has been an interesting archaeological exercise.
Love it Steve. I was told that the longer the taper, the finer the adjustment. Up to a point, Ha..... so the actual degree is not super critical, as long as it seats.
Another way to reshape and save money. Winner.
Steve,
The tip is much appreciated!
Now tell me this, what are the symptoms of a damaged needle?
Thanks,
Orlando
Fan-T-astic! That is a great how to. Thanks for passing it along
Symptoms of a damaged needle? My experience was the mixture adjustment still appeared to work as it should, in that the engine ran rough either side of an obvious sweet spot. But, regardless of that, the mixture was still way too rich with clumps of carbon forming on the diff housing and constantly fouling spark plugs. It was because the mixture adjustment appeared to work as it should, I was misled and it took a couple of years to find what was really wrong.
I turned down the needle using a drill and file and what a difference!
"The mixture adjusting needle in conjunction with the orifice is intended to control the mixture throughout its operating range, giving predictable and desirable fuel flow at any speed." The book doesn't say it in so many words, but I gather that a damaged needle, as you adjust it, is likely to take you from almost OK to almost OK, skipping the OK in between. From almost enough fuel you'll go directly to too much fuel.
John and Steve,
Thanks for the information, explanation and the video. This has made me want to go check.
Once again, I've learned something new here from you all.
Very much appreciated.
Orlando
Steve,
Thanks so much!
Respectfully submitted,
Hap l9l5 cut off