leaky carbs

[cddetelich]

Motor is a 1989 175 J ohnson V-6 with three 2-bbl carbs. Bought the boat last year. When at dock, I would tilt up motor, then I realized the carbs were leaking the fuel out of float bowls and I would have a hard time starting, trying to fill bowls and yet not flood engine. After several attempts I just left engine tilted down and starting was a lot easier.
Are these carbs difficult or expensive to rebuild? Wouldn't this solve the problem and let me tilt the engine without all of the fuel leaking out of the floats?

 

[tashasdaddy]

Re: leaky carbs

never rebuild one of those, but it needs to be.

 

[ezeke]

Re: leaky carbs

The carbs are easy enough to rebuild. The kits list retail at around 29.00 per for the OMC/BRP #439076. You would need three kits. You need a service manual.

The aftermarket kits are half that price but don't come with floats.

It would be unusual to find all three carburetors leaking from float problems at the same time, so check the primer first.

 

[Joe Reeves]

Re: leaky carbs

Your problem is that you're attempting to do what should not be attempted.

The floats are set to function when the engine is in its running position. When you tilt the engine, you're changing the float level to a setting whereas it is impossible for the float needle valve to seat and therefore fuel will be allowed to flow thru the carburetor, spilling out the front of the carburetor throats.

(Carburetor Float Setting)
(J. Reeves)

With the carburetor body held upside down, the float being viewed from the side, adjust the float so that the free end of the float (the end opposite the hinge pin) is ever so slightly higher (just ever so slightly off level) than the other end. And when viewed from the end, make sure it is not cocked.

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store

 

[cddetelich]

Re: leaky carbs

Your problem is that you're attempting to do what should not be attempted.

The floats are set to function when the engine is in its running position. When you tilt the engine, you're changing the float level to a setting whereas it is impossible for the float needle valve to seat and therefore fuel will be allowed to flow thru the carburetor, spilling out the front of the carburetor throats.



I understand your point of view, but wouldn't this mean the motors were never meant to be tilted up at dockside? If so, why do they all have power tilt? And why is is recommended to svoid growth?
(Carburetor Float Setting)
(J. Reeves)

With the carburetor body held upside down, the float being viewed from the side, adjust the float so that the free end of the float (the end opposite the hinge pin) is ever so slightly higher (just ever so slightly off level) than the other end. And when viewed from the end, make sure it is not cocked.

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store

 

[Joe Reeves]

Re: leaky carbs

Your reply..... "I understand your point of view, but wouldn't this mean the motors were never meant to be tilted up at dockside? If so, why do they all have power tilt? And why is is recommended to avoid growth?"

No offense intended here but I want to make it clear that my statement is not a point of view, it is fact as stated by OMC and a known aspect of mechanical design.

The Power Tilt Trim design is designed to operate in the trim rage to 15° only (In/Out). If that 15° was exceeded while under way (if the engine moved at all), the pressure being applied by the propeller would force the engine back to that 15° position.

Although the engine, after being started, will run properly at that trim position.... it will not start and run properly if starting is attempted in that position OR a greater tilted degree.

It is recommended, as you state, that the engine be tilted to its extreme tilted position in order to avoid marine growth.... however the engine is not running in that position. That would be the non running position if the boat is being stored in the water at a marina or your local dock.