Trying to get some stick time with my high wing trainer before I maiden My new Tiger 60.
I've been having trouble with this TTPro .36 for awhile.
I can hear it " breaking down" while flying half throttle.
Transition is rough. didnt idle well.
One of the guys at the field helped with the low end yesterday. He did a pinch test of the fuel line and we thought we had it running pretty well. Idles nice and low, transitioned well right up to full throttle
(probably turned in the low speed about 3/4 of a turn.) I had to leave the field yesterday so I went out today to test the new settings.
Started right up, nice low idle and ran smooth right up to WOT.
When I took off I could tell I had less power than usual. One of the guys behind me yelled out it sounded like it was "leaning out" I flew a couple laps but it wes breaking down in flight still so I landed.
It was suggested to "richen up" the high speed so I did but results were no better.

Its no fun flying with a bad running engine!

tunning this engine is the hardest part of flying...

Theres only two screws, you wouldnt think it would be so tough..


Steve

part of the hobby,could be a bad plug, dirt in carb or improper adjustment.you will have to do trial and error on the setting.

First off take a good look ant your fuel tank and lines, including the stopper and clunk line in the tank. Even the tiniest air leak can cause issues.

Once you are confident all of that is OK, make sure your carburetor, back plate, cylinder head, etc. is tight and leak free.

Fire the engine up and let it get warm. Advance to full throttle and adjust the high speed needle a small amount at a time until you achieve maximum RPM. You should know this just from the sound; it will be screaming. Then back the high speed needle out a few clicks until there is a slight RPM drop. It is always better to be too rich than too lean on this setting.

Once the high speed needle is set, it is time for the low speed. Pinch the fuel line going to the carb. If the engine quits almost immediately it is lean. If the engine speeds up noticeably and runs for a while then it is rich. If it runs for a short time then fades & quits then it is likely close. Adjust as needed. Verify your adjustment by checking the transition. It should be smooth & quick. If it immediately falls on its face & quits then the low end is too lean. If it hesitates & spits a little then it is likely rich. Adjust as needed to get a good transition and reliable idle.

Once the low end is set, go back and check the high speed again and adjust if necessary.

Another thing to consider is your glow plug. Whenever you are having engine trouble, put in a new one. This will at least rule that out or it might even cure the problem.

Another tip that I think a lot of people need to learn is that once you get the engine running good, don't mess with it. I see too many people who ruin their flying day fiddling with the needles. It shouldn't need any other adjustments unless you change fuel types or there is a significant change in the weather. Even then, it should only need slight adjustment.

I changed the plug yesterday, no change.
I do want to take a look at the fuel tank and lines. I'll just replace the lines when I reinstall the tank.

Does it mean anything if it runs well on the ground but not in the air?

Right now it seems good on the ground...?

I do see fuel leaking around the muffler gasket.

I'll follow your instructions. I'll get to the field after work when its not so crowded and I can hear / concentrate.

Inst. call for 2.5 turns out to start. I'll Turn in to lean or out to richen, one way should increase rpm?? How far in or out would be unusual? would 1 full turn be unusual?

I've tried variations with the high speed needle so I'm thinking fuel line or low speed needle???

steve

Well, it's really not "under load" when on the ground. Sure, the prop turns, there is resistance, and some prop drag, but not like in the air. The engines load up differently, the props work differently, and it all ads up to different in the air as compared to on the ground. I don't have an answer for you because all that hs been mentioned already, is what I would do. Someone will come up with a good suggestion that will certainly help.

You also might think of having someone with experience at your club field look at it. They might be able to help you clear up the problem.

CGr.

the clunk in the tank should be about 3/8" in front of the back wall not touching it.

I agree that it is frustrating when your engine is not running properly. What I have found though is that by troubleshooting, you end up learning a lot. You will figure this thing out eventually, and will know what to do and what not to do in the future.

I'm still learning, too. I had two dead-sticks yesterday, one just off a touch-and-go and it could have gotten pretty ugly. Luckily I only ripped the landing gear block out of the plane and was able to make the repairs in one evening. Could have been much worse. The bright side is I learned something and have one more tool in my engine tuning toolbox.