'81 115 how many turns idle mix screws

[olemerc115]

just wondered what the factory settings were on a inline 6 2 stroke 115, on the idle mixture scres, I think they are set at 2 turns out on all 3 carbs but I cant remember, I checked mine and they were at 1 1/2 out and was bogging until planed off, then I set them to 2 1/8 it helped but it still wants to bog on the bottom, I pumped the primer bulb while bogging and seemed like it got worse, I reset them to 2 1/2 out today gotta take it out soon, I acts like it isnt getting enough fuel, but I dont know, I have posted before but the compression is good and the plugs are not steam cleaned so no water in the cylinders, this bog until planed is a real pain, thought I had it fixed but I guess not, I am thinking it is in the carbs and not ignition related becuse when you hit it while planed off it screams and will run fine, also when loading the boat onto the trailer, once you have the boat on and you give it some throttle to ease up, more on the trailer, it bogs and want to stall out, like it has no power to drive itself up on the trailer any farther, I know this isnt right because you see other people throttling there boat hard and it goes all the way up on the trailer, I gotta get this motor more throttle response on the bottom, it should have more torque than it does, any help please and thanks again

 

[Laddies]

Re: '81 115 how many turns idle mix screws

Basic setting should be around 1 1/2 turns if the bog is mid range try removing the back drag jets and see if that don't stop it, also low float levels and plugged low speed pickup tubes will do the same thing.

 

[olemerc115]

Re: '81 115 how many turns idle mix screws

which ones is the back drag jets, can they be removed without removing the carbs? I have a manual but cant find where they are and how to remove them, thanks again

 

[Plainsman]

Re: '81 115 how many turns idle mix screws

Are those the small black hoses that run over the top of each carb Laddies?

 

[olemerc115]

Re: '81 115 how many turns idle mix screws

I need to fix this thing pls help guys

 

[Plainsman]

Re: '81 115 how many turns idle mix screws

 

[tredragon]

Re: '81 115 how many turns idle mix screws

ed (emckelvy) recommended to me to tune it (warmed up, idling in the water) until the idle was reallllll purty. Then richen it up (CCW) a bit and try a hole shot. If you bog, turn it more rich, CCW, and try again. If you get a real lopey idle, adjust idle speed to compensate. I tuned in the bucket and she ran fine, started great on the water. Wondering if I even need to tune more since we don't ski and only plan to fish/tube.

 

[CWKboat]

Re: '81 115 how many turns idle mix screws

I set my 1500 2 1/4 turns CCW and it ran great. You can take those black hoses off and just plug them with some automotive type emission plugs I think. You don't need the back drag feature which was designed to lean out the mixture at mid range for fuel economy. Lean is BAD for those inlines so I've heard especially with today's fuels.

 

[honestcharlie56]

Re: '81 115 how many turns idle mix screws

one thing you might try is disabling the enricher solenoid, that stupid thing aint worth crap and it will cause a wierd idle, and make ya bog down on the hole shot sometime, i disable mine after shes warmed up and it runs like a top now.

 

[gregpro50]

Re: '81 115 how many turns idle mix screws

one thing you might try is disabling the enricher solenoid, that stupid thing aint worth crap and it will cause a wierd idle, and make ya bog down on the hole shot sometime, i disable mine after shes warmed up and it runs like a top now.

An '81 wont have the solenoid. It will have an actual choke. Also the enricher only works or should only work when you push the key in. I actually changed my older Merc over to the enricher solenoid setup because it works better for cold starts.

 

[olemerc115]

Re: '81 115 how many turns idle mix screws

thanks again for the replies I want to remove the back drag hoses, so I just remove the hoses and vacuum cap the nipple on the carbs right, is that all I need to do to remove this feature, my choke just works when you push the key in, works fine on cold starts, thanks again