Ignition coil, carburetor, intake system
Ignition coil, carburetor, intake system
Ignition coil, carburetor, intake system
Ignition coil, carburetor, intake system
Ignition coil, carburetor, intake system
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Sure. All the periphery. As was mentioned. Step by step.
Followig which hypothesis?
The hypothesis of Sir Arthur Conan Doyle: When you have excluded the impossible, whatever remains, however improbable, must be the truth.
I find this thread odd, in some way…
Everything outside the engine was changed, yet there is this apparent massive loss of speed.
I wonder if it is yet another case of the shop saying “we changed X” but actually they haven’t. That omission sends everybody around in circles. We had a TB20 owner on here recently with a similar thing; turned out there was one thing the shop had not changed…
But still no answer to any of the Qs I asked earlier. Obviously I have no more right to answers than anybody else 
but I find it curious. No fuel flow data… no EGT data…
Has the OP considered removing engine and sending to engine shop for testing on a dynamometer, would be reasonably straight forward to find the problem. The only downside is it would not find any problems with prop or governor.
Quote No fuel flow data… no EGT data…
Don’t forget MP too as well as telling sources of FF data.
If the engine and accessories have been to shop, then these three will lead you in the right direction for troubleshooting.
Thank you for your suggestions and tips!
Today the propeller governor arrived from the overhaul…tomorrow we will do the runup and capture more accurate data.
I will tell you about the result,
Have you had a chance to check that fuel tank vent lines are not partially or fully blocked?
