Leaking Carburetor Cause Discovered.

[Alex Clark]

As a follow up to my previous, and poorly explained, post about my leaking carb on the 12.
It turned out the float decided to be a submarine. See attached photo. So it filled full of fuel and sank.
Thus it was flooding like crazy. So a new float is on order.
I have never seen a semi-clear white float before. It has a Eagle or Hawk face logo.

As I am sure you know. there was a 2009 service bulletin regarding improper floats in Marvel Carbs.
https://msacarbs.com/pdf/SB-2_B_RPLm...ats_062209.pdf

We also discovered that the primer lines were spraying fuel into the engine compartment every time the primer plunger was pushed. This was adding to the fuel dripping all over the place. So that is the next thing on the list.

NOTE: The IA who installed my new aluminum tanks was not the IA who last tinkered with the carburetor.

[cubdrvr]

Preflight when cowling open I give a tug on each primer line..........they have a tendency to break off in the fitting that's not visible.

[Alex Clark]

Cubdrver
The fitting going into the cylinders were just fine. The major spraying leak was up above the carb behind the engine. Somewhat concealed.
The is a splitter fitting that sends gas from the one line off into port and starboard directions. When I pumped the primer it was spraying 5 inches out of the fitting.
You had to have somebody pump while you look. It was a nice mist. Perfect to start a friggen fire.

[DENNY]

I had my primer line brake at the T behind the engine last fall. What a major pain to fix.
DENNY

[ak49flyer]

Hope you got an Avstar brass float. The blue Marvel ones aren’t super consistent, apparently. Had a weird lean range on a fresh c-90 carb from Marvel, sent it back to them, came back the same. Talked to a highly experienced carb repair station up here, and was told to throw the Marvel float in the trash- apparently he sees this commonly. I didn’t listen the first time, gave Marvel a chance to warranty it, but after the second go-around, I put the Avstar brass float in, and totally cured. Anyone else heard of issues with these? And no, it wasn’t cracked or sunk…

[Skywalker]

If it wasn't cracked or sunk, it might be like my old plow truck, where a composite float distorted and rubbed the inside of the chamber. What does Marvel say about mogas?

[mvivion]

Hope you got an Avstar brass float. The blue Marvel ones aren’t super consistent, apparently. Had a weird lean range on a fresh c-90 carb from Marvel, sent it back to them, came back the same. Talked to a highly experienced carb repair station up here, and was told to throw the Marvel float in the trash- apparently he sees this commonly. I didn’t listen the first time, gave Marvel a chance to warranty it, but after the second go-around, I put the Avstar brass float in, and totally cured. Anyone else heard of issues with these? And no, it wasn’t cracked or sunk…

What was the “weird lean range” you noted?

MTV

[ak49flyer]

Missing at mid-range, particularly while running on only one mag or the other during a check. Carb heat would almost cure it completely, but the float did away with it entirely. Spent days troubleshooting, finally swapped carbs with another to conclusively rule out anything else, and it was indeed the new carb from Marvel.