Hi Ric,Your comments on the needle adjustment reminded me that over the years we have had to adjust them quite a few times. Mainly seasonally. Rob does an excellent job of maintaining the carbs and motor around those key factors you listed and worn butterfly spindles and perforated diaphragms come to mind, especially the latter. For any touring its wise to have a spare set in the 'fly away' kit as from our experience diaphragms are the most common part to fail. When checking for perforations by holding up to sunlight be very careful not to stretch them much as you may well do more harm than good! And...make sure that the locating lug on the diaphragm goes into its correct position on the carby body! Our Air Experience flights usually involve a climb to between 6000 and 7500'. Seasonally, we can notice poor running and loss of power as we approach these levels due to over rich running as confirmed by exhaust and plug colour. As Rob mentioned, usually 1/4-1/2 turn does the trick. Laurie Sent from Yahoo7 Mail on Android On Thu, 4 Apr 2019 at 12:43 am, Ric Sutton<[email protected]> wrote: #yiv8114659702 #yiv8114659702 -- _filtered #yiv8114659702 {panose-1:2 4 5 3 5 4 6 3 2 4;} _filtered #yiv8114659702 {font-family:Calibri;panose-1:2 15 5 2 2 2 4 3 2 4;} _filtered #yiv8114659702 {font-family:Tahoma;panose-1:2 11 6 4 3 5 4 4 2 4;}#yiv8114659702 #yiv8114659702 p.yiv8114659702MsoNormal, #yiv8114659702 li.yiv8114659702MsoNormal, #yiv8114659702 div.yiv8114659702MsoNormal {margin:0cm;margin-bottom:.0001pt;font-size:12.0pt;font-family:New;}#yiv8114659702 a:link, #yiv8114659702 span.yiv8114659702MsoHyperlink {color:blue;text-decoration:underline;}#yiv8114659702 a:visited, #yiv8114659702 span.yiv8114659702MsoHyperlinkFollowed {color:purple;text-decoration:underline;}#yiv8114659702 p.yiv8114659702MsoAcetate, #yiv8114659702 li.yiv8114659702MsoAcetate, #yiv8114659702 div.yiv8114659702MsoAcetate {margin:0cm;margin-bottom:.0001pt;font-size:8.0pt;}#yiv8114659702 span.yiv8114659702BalloonTextChar {}#yiv8114659702 span.yiv8114659702EmailStyle19 {color:#1F497D;}#yiv8114659702 .yiv8114659702MsoChpDefault {} _filtered #yiv8114659702 {margin:72.0pt 72.0pt 72.0pt 72.0pt;}#yiv8114659702 div.yiv8114659702WordSection1 {}#yiv8114659702 Hi Jarek While i do have some mechanical qualifications, please remember that what i say should by no means be taken as a rule or the final word. i am just as fallible as the next person. i am always happy to hear about information like you have presented here because in most cases it adds to my body of knowledge. Even if i find information of a dubious nature it may help me understand how or why people do things. If you get the impression that altering the main jet(needle) adjustment will improve the way your machine runs then absolutely get stuck into it and tell us what you found. Particularly if it means a few more horses to yank our birds aloft on a hot summers day. While mine sounds as sweet as a steel box full of chooks, wild cats, jack hammers and several crates of empty beer bottles rolling down a mountain, i probably aint gunna mess with it till something changes. (kidding- it runs a little better than that- replace “wild cats” with “highly excitable domestic cats”). Though, if it does change i would look for other causes like diaphragm holes, worn butterfly spindles, needle and seat not doing their job, blocked fuel/air filters, loose manifold/carb mounting bolts blah blah blah etc etc. i guess things wear and change but hopefully not too much. Out of interest, how often were you thinking of doing this? Fair weather ric From: [email protected] [mailto:[email protected]]On Behalf Of Jarek Steliga Sent: Tuesday, 2 April 2019 2:53 AM To: [email protected] Subject: Re: [DOG mailing list] Zenith 150 C3 meetering needle adjustment Rob, Ric, Thank you. I am going to follow your advice shortly. Ric, Your question 'why I want to do this' baffled me. I watched the attached video, I read some sections in the Zenith user's manual and inferred that the adjustment is a must. Do you think it's redundant or excessive? As for the vacuum gauges, I procured them even before reading your comments here and yes I will be very mindful of the man mincer :-). Best regards to both of you Jarek On Mon, 1 Apr 2019 at 15:52, Ric Sutton <[email protected]> wrote:
Hi Jarek For my two cents, i guess my question would be why you want to do this. But onwards and further to robs comments i check my throttle opening with vacuum gauges plugged into the balance pipe ports on the intake manifold. Yes the engine needs to be running but i sit in the cockpit- much safer than standing next to that spinning man mincer. The vacuum needs to be the same at idle and at wide open throttle and by the same i mean having identical readings between carbs not identical readings at idle and at full throttle...... eh you know what i mean. Good luck ric From:[email protected] [mailto:[email protected]]On Behalf Of Jarek Steliga Sent: Monday, 1 April 2019 4:18 AM To: [email protected] Subject: [DOG mailing list] Zenith 150 C3 meetering needle adjustment Hello everyone, I watched this video https://www.youtube.com/watch?v=wenBlytGjSI but is it of any use in the case of TWO carburators as is on my Limbach 2000? Is the meetering needle adjustment at all possible in this case? How should I go about it? Thank you in anticipation Regards Jarek
