i'm back on the track!!!!
as usual when i'm stumped with a mcculloch i ask the master.
my bdc 16 double pumper just wouldn't work right.
sent Steve a question or two and he sussed out the problem.
Now my kart goes like a ...... .. well you know fast
yeeesh i almost forgot KIDS are reading this stuff too!!!
anyway too much going on this week.
in the next week or two i'll write up a little tutorial on mcculloch rebuilds that may save somebody a mess of headaches.
most of my info is directly from Steve O but he probably won't mind me sharing.
i like bdc carbs .. i think if you machine them out a little install some real throttle shaft bushings helps alot .. i drill 1/16" hole in the bottom of the flapper on some it seems to help loading up on parade laps ..
You are correct Steve O'Hara is a guru on anything MAC and he is always willing and ready to help if you have a challenge with anything MAC. Last year when I was in the process of rebuilding my old Dart with a Mac 91 he was most helpful. One thing I did learn real quik that if you want the BDC carbs to work properly is check the pop off and the engine has to be airthight. These little bombs continue to amaze me as they are awesome.
if it wernt for gentalmen like steve O. scott K. and many many others there would be alot more blowed up and discusted mcculloch kart engine owners than one could imagine im still waitin for the tech ..
The Mac Carbs always seem to be a bit of a mystery however Steve fully understands what and how they work. As I had no knowledge of what make these carbs tick I went to Steve for help. As a result we did all the work at the shop and when we went to the track we only had to make minor tweaks with the jets and in most cases I never ever have to touch the jets. One thing we did find is the needles wobble in the seat and it make it very difficult to set the correct height on the inlet lever. Im very fortunate as I work with a karter from the late 70's and early 80's and he also understands the carbs. So guys dont give up on the carbs.
WOW, Thanks to all for the kind words. Good to hear the shared information is helpful for some... it doesn't always work out that way but that may be due to problems beyond the carbs that aren't known.
Just be fair I have to confess I ruined a lot of good carbs in the process of learning how to make them work.
Basic rule of thumb... they are pretty good just the way they came from the factory and they only need minor tweaks to make them real good. The challenge for vintage karters is simply that most of the carbs found today are not original and have been modified in one way or another or have a lot of wear and tear that has to be corrected. Most can be returned to near stock condition and made to work pretty good.