1977 Evinrude 175hp model #175749S rubber float bowl gaskets leaking

Replaced float bowl gaskets this yr while rebuilding carbs, new floats, needle and seats, everything new Evinrude/Johnson rebuild kits from Marine Engine.com. Should I have put some sort of rubber gasket sealer on these gaskets at float bowl and carb base? Keep getting oil residue below engine cowl where fuel leaks out of float bowls, gasoline evaporates and leaves black looking residue, also my primer bulb has to be reprimed after sitting for a while fishing from this small leak. Checked all fuel line connections for leaks just bowls leaking at new rubber gaskets.

Do not use sealer on float bowl gaskets !!-----------This black residue , are you 100% sure it is oil from fuel that has leaked ? --Is it the same colour as the oil you mix with the gasoline ?-----Are you tilting the motor while fishing ?

I'm tilting motor while out sometime if needed to get into some of the shallow rice fields and creeks affected by the tide. Once I tilt motor in these cases it stays where I tilted until time to leave. Never noticed this residue while tilting motor up at canal after loading boat back on trailer. Once I get home I've been unlatching motor and letting down so water will run out of engine for freeze purposes. I'm not 100% sure, but the last several times after running the motor, and getting home and motor has been fully tilted up and motor latched in full up position all the way home and looking for any leaks the float bowls are always very wet with fuel, just the lower half of the carb at floatbowls on two of carbs, the upper carb is not wet. The oil I'm using is Penzoil 2 cycle outboard oil, kinda blue/black looking to me. Thanks again for your replies and help. Screg

Racerone, Went out and looked at this situation I'm having with black residue and now believe this is burnt oil, smells burnt anyway. Removed hood on motor and looks like this sticky black residue is coming out of air silencer cover at front of carbs, maybe that little rubber hose from engine back to air silencer housing. Could this be timing problem? Motor runs like champ, cranks good after pumping bubble, does'nt seem to be missing.

That little hose is a safety item.----Any leakage from the carburetors is sucked into the motor to be burned.----------The timing on outboards is factory set and normally does not need adjusting for the life of the motor !!