1975 Evinrude Outboard Motor, leaking fuel !!

[bfmiller]

Purchased a boat and first time running the boat, needed some fuel injector to get it started. Ran for about 30 seconds, however a large amount of fuel/oil mixture was coming out of the motor below the carb and intake. Do you think it is a hose or seal? Would a new carb kit fix the problem? Any other ideas what it could be? First time working with boat engines so not too sure but think the problem is pre-carb.

 

[nwcove]

Re: 1975 Evinrude Outboard Motor, leaking fuel !!

welcome to iboats! but, ok ....what motor, hp etc etc? more info is needed.

 

[bfmiller]

Re: 1975 Evinrude Outboard Motor, leaking fuel !!

I'll get model number

 

[bfmiller]

Re: 1975 Evinrude Outboard Motor, leaking fuel !!

welcome to iboats! but, ok ....what motor, hp etc etc? more info is needed.

Manufacturer Year Horsepower Model
Evinrude 1975. 115 115593

 

[emdsapmgr]

Re: 1975 Evinrude Outboard Motor, leaking fuel !!

It's not unusual for those carbs of that vintage to weep a little fuel-esp if it's tilted up after running. Any fuel that weeps out of the carb throat will accumulate in the bottom of the airbox. Usually the excess will get sucked into the lower engine cylinder through the airbox drain hose, where it will get combusted during running. In your engine's case it sounds more than normal. You may want to overhaul both carbs. Tear them down, clean and reassemble with new carb kits. Also, make sure your airbox drain hose is connected/operational and that the airbox halves have a sealing gasket between them. If not, any excess fuel will just run into the lower cowling. Double check the fuel line hoses to make sure they have not deteriorated. Orignal fuel hoses from 1975 are not made ethanol-resistant. Today's ethanol fuels will degrade original hoses, causing leaks and other problems.

 

[bfmiller]

Re: 1975 Evinrude Outboard Motor, leaking fuel !!

It's not unusual for those carbs of that vintage to weep a little fuel-esp if it's tilted up after running. Any fuel that weeps out of the carb throat will accumulate in the bottom of the airbox. Usually the excess will get sucked into the lower engine cylinder through the airbox drain hose, where it will get combusted during running. In your engine's case it sounds more than normal. You may want to overhaul both carbs. Tear them down, clean and reassemble with new carb kits. Also, make sure your airbox drain hose is connected/operational and that the airbox halves have a sealing gasket between them. If not, any excess fuel will just run into the lower cowling. Double check the fuel line hoses to make sure they have not deteriorated. Orignal fuel hoses from 1975 are not made ethanol-resistant. Today's ethanol fuels will degrade original hoses, causing leaks and other problems.

Thanks, I do not think this is normal though. It was a large amount of fuel and the engine would not idle or fire up unless direct either in the intake. I'm gonna try and clean the carb and replace the parts with new ones in the kit. Hopefully that will fix it. Otherwise are there any other valves or lines that maybe damaged which would cause a large amount of fuel/oil to come out?

 

[emdsapmgr]

Re: 1975 Evinrude Outboard Motor, leaking fuel !!

The carb kits should come with a new needle and seat. Perhaps the cause of the original leak. Some of these early original carbs may have come with cork floats. The varnish outer layer on the float can deteriorate (no longer float in gas) with age and the floats can sink, causing flooding. Your new factory carb kits will come with new white plastic floats which won't deteriorate with age. Hopefully, this will take care of it.

 

[bfmiller]

Re: 1975 Evinrude Outboard Motor, leaking fuel !!

The carb kits should come with a new needle and seat. Perhaps the cause of the original leak. Some of these early original carbs may have come with cork floats. The varnish outer layer on the float can deteriorate (no longer float in gas) with age and the floats can sink, causing flooding. Your new factory carb kits will come with new white plastic floats which won't deteriorate with age. Hopefully, this will take care of it.

Thank You, I replaced carb kits on each carb. Problem seems to be solved as far as the leak. Now the boats fires up however will not idle or run when i lower the warm up lever to below 3000 RPMs. Thoughts on what may fix this issue? Spark plugs or something not firing right? The engine kinda of sounds like its misfiring but I am not sure since i do not know what this motor sounds like healthy

 

[emdsapmgr]

Re: 1975 Evinrude Outboard Motor, leaking fuel !!

Probably not a good idea to idle the engine at 3000 rpm's. When you overhauled the carbs, did you remove all the jets and clean the upper carb bodys with the proper cleaner (such as a Gumout type product?)