Brodak 40 Speeding Up

[Sam Laughery]

I have a Brodak 40 on my Cardinal that has been running absolutely perfect all summer.  I haven't changed anything.  Last Saturday I started out at the same speed as always (about 8800 RPM) and within a few laps of taking off the speed increased at least 1000 RPM.  Any ideas?

[Mark Scarborough]

perhaps more about your setup will get you better answers. off the cuff with no other information, I would say that if you are using a uniflow tank, something inside the tank failed causing it to lean, a leak somewhere, actually come to think of it, if you use muffler pressure It is likely the same thing. If you bleed muff pressure it will go lean on you. happened on my vector this weekend.
Other thoughts, have you changed fuels, brands or gallons of same brand?

[peabody]

A couple of things to look for, assuming no external changes:
1) crap in the fuel line....clean it carefully.
2) leak in the tank....or a split tube inside it.....
3) The nose loosened...either because of a glue situation or because of impact...

Hope these work...

[Dennis Adamisin]

Ditto the above suggstions, to which I would ask: after it speeds up does it hold steady at the faster setting or is it erratic?

[Mark Scarborough]

one last thought, crud in the needle valve or clogged filter can do the same thing

[Andrew Borgogna]

Look for pin hole in the fuel line, I had that problem on my B-40.  The cause was repeated removal of the fuel line to fill the tank.  Drove me nuts (I know its a short drive) until I found it.
Andy

[Garf]

Pressurise the entire fuel system. You would be surprised how often you find leaks where you least expect them.

[john e. holliday]

My last leak was of all things, the metal fuel filter I use.  Tightened it and all came back to normal.  Have fun,  DOC Holliday