Sport jet carbs

[Mike Watson]

As with most it seems my carbs on my 1996 Sport jet 120 need attention. I was wondering if anyone knew of a place that sells rebuilt carbs. It would be easier just to swap them out then to find out the hard way that I'm no good at rebuilding them. Also my motor is extremely hard starting. I ran down a new battery the other day trying to get it to start. It eventually did and smoked like crazy for a few seconds. I've heard this could be a fuel pump diaphram leaking. Has anyone out there had any experience with this type of issue? I looked for a choke and don't seem to see any type of manual butterfly type of choke but there is a small device that has hoses attached to it. Any help would be appreciated.
Mike

 

[jcyamaharider]

Carb rebuilds are super easy and way cheaper then new carbs. Just look it up on youtube.

 

[Ronnie]

I had a boat with a 175 hp 6 cylinder 3 carb sport jet that became hard to start. I eventually took it into a Mercury certified mechanic to have the carbs rebuilt. The needles on mine were deteriorating and were replaced during the rebuild. The kits were around $75 per carb but labor was a little over $100 per carb this was almost 15 years ago. It's a two Stroke so lots of smoke on startup especially after a hard startup is normal.

If you go the rebuild route and don't have experience doing so I recommend you have a shop do it. If you insist on doing it your self be sure to check and note the high/low and idle screw settings on each carb (e.g. 2.5 turns out from closed). Also brush up on your pop-off tuning skills.

 

[Brad_Ct]

I don't think the 120's had actual chokes on them they used a fuel enrichener system but I have no idea how they worked. I would find someone to rebuild the carbs. you have if you are not able to do them yourself, I also believe that new carbs. are obsolete. Best bet would be if you don't already have one is buy a service manual for the engine. I found several on ebay for my 90hp.

 

[Bilmon]

http://www.boatinfo.no/lib/mercury/manuals/90-120_sportjet.html#/0

 

[Mike Watson]

Thanks for all the help. I may just tackle those rebuilds myself.

 

[Brad_Ct]

They are not hard to rebuild, the only issue I had was setting the float levels. I set them per the specs. and fuel was pouring out the throat of the carbs., had to set them lower to stop it.

 

[Mike Watson]

Ok I went to buy carb kits and the guy wants me to give him the numbers off the carbs but couldn't tell me where the numbers are located. Anyone know where these numbers are. I'm hoping I don't have to remove the carbs to get to them.