Brown fluid from scavenge tube

[Crazer]

My engine stalled out twice today while test running. I think I have isolated the issue elsewhere in the fuel system, but while trouble shooting I did notice a brown, odorless fluid that appeared to be leaking from the scavenge tube at the bottom of the carb. The fluid was not on any other part of the engine, so that rules out something like an oil leak, presumably. Does anyone know what this mystery liquid is and why it's leaking from the scavenge tube? It wasn't gasoline, or at least it didn't smell like it. I didn't try opening up the carb to see what was inside, but the only thing that should have been going in was new fuel from a plastic outboard tank.

I should add, the engine fires up easily enough, it took a little cranking today, but I didn't even have it choked. It ran good until it stalled, and the suspected cause of the stall was a pinched fuel line. Pumps water well, no other issue except a persistent high oil pressure reading that I have yet to resolve.

[Dave Neptune]

Not bad or good!

First, is your scavenge tube still hooked to the manifold too? Then you just have a loose fitting and a fuel dribbling problem. If your engine starts without the choke something is wrong. When the carb is adjusted for a proper idle it is almost impossible to start cold without the choke. This leads me to think that the carb is also compromised or seriously out of adjustment.

The brown residue is not really normal but it is what the fluid (fuel, dirt,oil and moisture condensing from the pressure changes) looks like when droplets are flying around in the throat instead of being delivered to the combustion chambers. The tube takes the goo directly to the manifold.

Dave Neptune

[Crazer]

Forgot to add, carb was rebuilt and I have not had time to adjust the idle yet, which is the whole point of running the engine to begin with. Yes, the starting without choke is not normal!

Okay, I will try tightening things down and assume that will fix the problem. Thanks!