HELP!! Lower Carb Leaking and other stuff

[RDSJR]

I have a 74 (i think) 3 Cyl MERC 650. I have got it running but the lower carb is basically pouring fuel from the stem in the middle of the carb, then leaks down the front of the motor.It starts OK, but I havnt had it on the water yet. I am assuming that I need to remove the carbs and clean them, but that is about all I know how to do. Is it hard to rebuild these? Or is there anything else I can try before removing them.

Also the prop on one of the blades is scuffed up...will this create a serious problem? Thanks to anyone that can help. I am in the military and just trying to spend some time with the family, thought this would be sumthin great for me and the son to do together. Thanks

 

[reddogg]

Re: HELP!! Lower Carb Leaking and other stuff

You need to rebuild your carbs, It's not hard to do. It will probibly take you longer to get the carbs off than it does to rebuild them. As far as your prop, if it is damaged enough it will become unbalanced and can eventually cause damage to your gears.

Red

 

[DamianJP]

Re: HELP!! Lower Carb Leaking and other stuff

Hey RDSJR

First off thank you for serving us.

Carbs are easy , but are overwhelming at first glace because of alot of little parts and the tight space to work with getting them off and on. A manual would help alot, very good investments.

Has the motor been sitting awhile? Sometimes with premix , the mixture will sit in there then the gas will evaporate abit and leave a nasty sludge that kind of hardens. A mix of varnished gas and unburnt oil.

You can tap lightly on the bowl part and/or casting in a area that will not harm the carb to try and unstick the needle. Fuel coming from there is probably a stuck needle/ flooding out the carb until overflow.
Or try carb cleaner / mabey a fuel additive to try and break up anything. Chances are it *might* work but it will break up the crap and get sucked into a jet area or some where else and create more problems. Best bet is to do a rebuild.

Dunno about the prop. If it alittle scuffed don't worry but I don't know how bad it really is. Post a pic if ya could. As long as it not vibrating , throwing the propeller out of balance your okay.

Let me dig around I might have a digital manual on my PC somewhere.

DamianJP

 

[DamianJP]

Re: HELP!! Lower Carb Leaking and other stuff

Sorry to ask before last post, Whats your serial number on the engine need to find the exact Year/Cylinder # for manual.

Check this manual out and see if it look like it has your 650 in it. Says all 650's from 1972-1976.

 

[hotrod53]

Re: HELP!! Lower Carb Leaking and other stuff

If you have never rebuilt your carbs before, it's not a hard job but a little insight will help. When I did mine, I unplugged the power to the motor, removed the starter (just 4 bolts and one wire), and you have to remove the top carb first. Removing the starter gives you a lot more room to get in there. The plastic choke linkage is funky, you have to twist it to get it off, fortunately its pretty tough. Be careful with the plastic link between the carbs, it's fragile but still available, guess how I know. Expect trouble from the lower carb bolt that is closest to the starter, try a few box wrenches untill you find the right one. It's tight in there and finding the right wrench is key, I tried 3 until I found one that worked.

Sounds like a rebuild in in order in your case, if you have Tillotson carbs with the blue fuel inlet piece, replace them too. I found that if you have an older motor those will become deformed over the years and may not reseal when reinstalled. They are dome shaped and tend to start to flatten out creating a sealing surface that is no longer flat. Buy new ethanol compliant float needles too while you're at it.

 

[RDSJR]

Re: HELP!! Lower Carb Leaking and other stuff

Thanks for all the info. I have the carbs removed and wasnt to bad to remove, I was expecting alot worse. I am picking up the rebiuld kits tomm and will start to rebuild. Also getting a new prop, I dont want to chance the damage that may occur with the old one. I will update to let know if the rebuild solves the problem. Once that is done it's time to tackle the electrical system, and im sure that is going to present a whole new set of challenges!

Also DAMIAN JP thanks for the manual, but I didnt see where it was attached in the message. Thanks.

 

[RDSJR]

Re: HELP!! Lower Carb Leaking and other stuff

I will get the SN for ya...thanks