Help please

[Nick12]

Hi everybody.
I have purchased this boat recently, it has twin 787 rotax engines and boat is 1997 seadoo challenger 1800.
I have dilemma with one hole that is on Starboard engine only. Its located on left hand side right beside carb. (As shown in pic.) . When I run my engine it spits gas mixed with 2 stroke oil right out through that hole. If I close this hole with my finger I can feel air being blown out from it and I can hear engine changing the way it sounds. I am really not sure what to do with it. Right now it has metal hose connection installed in this hole. I am afraid to seal it. The funny thing is the fact that this hole does not exist on PTO engine.
PTO engine have one hole on left side, which is used to return any unused gas back into carb. I wonder what to do with it? There is no extra connection on carbs for me to install fuel line on it. Any help is greatly appreciated. Thanks

 

[salmonkiller01]

I am pretty sure that is the pulse line for the fuel pump. I am not sure how your machine is running without it. Maybe one of the pro's can give you more info.

 

[glenwhitt]

Pulse line is on mag end. This looks like pto end. Have you gone through the fiche to find this? Start with fuel system then the block when viewing.

 

[Nick12]

Pulse line is on the other end and there is hose from there to carburetor. Like I said, the other engine have only one pulse line. Seams like starboard engine t have two????? One on each side. The only problem is that I do not know where to connect it as there is no extra connection on the carburetor side where fuel pump is. I am really confused here. Shop manual does not show this either.

 

[glenwhitt]

I have never heard of these having a fuel pump in the pto carb so this being a pulse line... i doubt it. What do you have for carbs, sbn40's?

Does it look like someone has put this in or does it look factory with powder coat and all. If factory looking maybe you can take the pic to a dealer and ask what up. You misslead them and say if it is something important then you want to bring it in and get it fixed. Make sure they tell you what the heck it is though.

 

[Nick12]

The only problem with dealer in my area is that I have to wait two weeks. I was hoping that somebody here knows what to do.

 

[Nick12]

I wonder if T-connection between pulse line and this hole and than back to carb would be appropriate solution?

 

[popasodatastie]

That could work i was just looking at my 787 and i olny have one fitting.

 

[Nick12]

Thanks for your help. It seams like that is proper solution.
I have same thing. One engine have only one fitting. The other have too. Beats me.

 

[Nick12]

I will wait for more input from you guys. I wonder if this engine was modified for better performance?

 

[kustomkarl]

I owned a 1997 challenger with a 787 engine in it. There is not suppose to have a nipple installed in the casting there. I checked the manual also, the only thing that should be in the case is 1 Pulse fitting going to the MAG carb, and 2 lines from the injector to the bottom of the Case on each side of the engine to lube the Rotary Valve shaft. There is not suppose to be a fitting in the place you see it in. In the stock case it appears like you could drill and install a nipple in this location, but you shouldn't. Plug the nipple. Look at the other engine in the same place and you will see what I'm talking about. If you don't plug the hole it might end up seizing the engine as it is allowing extra air into the bottom of the engine. I checked 5 different manuals to see if maybe I missed something along the way...Plug the nipple, it does nothing.

I also notice that in the pictures, it has oil residue all over the bottom of the hull. It must be from the open nipple.

Karl

 

[Nick12]

Thank you Karl. I believe that you are right. This nipple is not shown in manual. I will seal it with plug. I will be going out on lake this weekend and after I come back I will post how everything went. In the case that anybody have similar dilemma it will be helpful. maybe somebody was trying to get better performance out of this engine.

 

[Nick12]

Oil residue was from previous oil leak from return oil line located under muffler. That is fixed now.

 

[kustomkarl]

Oh ok...that open nipple would blow oil all over the place too. Uh...you might want to clean up the mess before you launch it again so if you do get another leak you'll know it is fresh oil, and not an old forgotten problem.

Karl

 

[custompartsguy]

Got a match? lol sorry

 

[Nick12]

Its OK.
Little bit of humor is always welcome.

 

[Chester]

That is a pulse fitting. Do not "T" it off with the other one. You must plug it. That additional pulse fitting is a common modification when you add a second fuel pump to the rear carb. I've done this to several engines but it's not needed with a stock engine.

Chester

 

[Nick12]

Thank you Chester.
I feel very confident now that I can see that two experts agree that this hole should be plugged.

 

[Nick12]

Thank you all for your help and advice. I sealed that hole and post next wekk how everything went

 

[Nick12]

Everything worked good. Thank you guys for your help.