1985 merc 115 hesatation an dies

[webster101]

ok guy's i know this one might have been covered but here goes.i have owned this boat foe over 10 years with no prob's till now just this year the motor wants to hesatate if not die on acceleration.the primer bulb never goes soft.and always starts right back up and after puting up with this the last 5 times out i replaced spark plugs and its got worse(not becuse of the plugs)i am a retired honda auto tech so i am mechanicaly adapt even thow i cant spell.i have not tryed to use choke when this happens but know if i did i would be able to determin if its a fuel or spark prob.water is not close so all test i could do at home would help.

 

[webster101]

Re: 1985 merc 115 hesatation an dies

also motor only does this while in gear in newtral acelerates fine

 

[webster101]

Re: 1985 merc 115 hesatation an dies

also motor only does this while in gear in newtral acelerates fine

 

[Clams Canino]

Re: 1985 merc 115 hesatation an dies

Might be time to clean the carbs. Also search on and do my "timing and synch" post.<br /><br />As they age you need to warm them up more too.<br /><br />-W

 

[Bob H.]

Re: 1985 merc 115 hesatation an dies

Time to split and clean the carbs.

 

[webster101]

Re: 1985 merc 115 hesatation an dies

ok guy's im with you on the carb overhauls but explaine why motor accelerates normal while in newtral? and as far is the timing issue i have never made any adustments to timing so why would that change all by itself.any help on carb o/h <br />?do i need gaskets can i just take apart and clean?can i do this on motor?any other issue<br />'s i need to know about or possibilites?thanks to all

 

[Chris1956]

Re: 1985 merc 115 hesatation an dies

Web, The motor will rev up in neutral since there is no load on it. A load causes it to need a richer mixture to allow acceleration. You can reuse the gaskets if they are in good shape (which is doubtful). Gasket kits for that motor are less than $5/carb, and readily available.

 

[webster101]

Re: 1985 merc 115 hesatation an dies

ok overhauled all 3 carbs they where clean no visual dirt of failures while testing boat in water seemed better but the longer i ran worse it got same prob dies and hesatates on accel.press tested fuel pump read 1/2 of manufactures specs at idel and evan less at w.o.t overhauling fuel pump tonight will test this weekent and update on outcome

 

[Clams Canino]

Re: 1985 merc 115 hesatation an dies

Never rev it over 2000 in neutral. It **can** fly apart running fast and loose with no load.<br /><br />-W

 

[webster101]

Re: 1985 merc 115 hesatation an dies

thanks for the info on rving in neutral clams. just got done replacing all fuel pump gaskets they looked very tired and old i think this will fix hesatation fuel pump press gauge did pulse in a negative direction when reving somehow i dont think it should.plus at idle only read like 2 psi mayby 3psi and with boat in water just after it would die when accerating if i idled for a while would accel ok(must have filled carb bowl also when going at top speed when i could get there i did feel a slight serging.testing boat on saterday I will update on outcome

 

[webster101]

Re: 1985 merc 115 hesatation an dies

help....this makes no sence boat still hesatates no dies while accelerating idles fine replace all fuel pump gasket's cleaned all 3 carbs {nothing to clean they where fine)had fishing partner with me so tryed some tests.started to accerate till motor started to bog out hit electric choke(merc also calls enrichner solenoid)died flooded out.same test only had fishing partner pump primer bulb took right off? did this three time to verify not a fluke.this makes no sense to me!please anyone help how bout you Clams any ideas?bulb stay hard all the time.