1988 100 HP Merc

[abig62dog]

I recently purchased my first boat. It has a 1988 100 HP Merc motor. It does not want to idle unless the throttle is all the way up and dies when I try to put it in gear, at a high or low idle. I have changed the plugs, but that has not helped. Any suggestions would be appreciated. I am LOST!

 

[b.gagnon]

Re: 1988 100 HP Merc

I hate to say this but I had an 88 115 merc that did the same thing and it was due to a bad cyl.. top speed was fine but it would die before you put it in gear..I hope the same is not true for you. There are a bunch of things it could be but that year merc tends to have oil inj probs......<br />GOOD LUCK!!!!!!!!!!!!!!!!!!

 

[aban_esox]

Re: 1988 100 HP Merc

Hey Dog;<br />Been there! I've had my 88 100 since new and have had minor problems such as yours.<br />I've had fortunatly the advice of the great folks on this board.<br />First-if you just got this ob-how long has that gas been sitting. I would suggest if you don't know, drain fuel tank and put in fresh fuel and add a dose of (sorry 12 footer) sea foam additive. Put unit in water at the ramp-I repeat-at the ramp to asure proper water flow. Fire her up and let her idle and warm up. CHECK FOR TELL TALE STREAM.<br />The reason for this advice is I just put my 100 in the water last weekend after 3 years.<br />I did what I suggested to you. When I first fired it she smoked, choked and ran for crap. I backed from the ramp and tried to put it forward no less than 12 times until I feathered her into foward. Idled terrible for awhile and chugged and spurrted and low and behold I had my 2 cylinders firing at idle (2+2 you know). When I hit the hole shot she took off and never looked back.<br />Since then I have added fresh gas to dilute somewhat the additive.<br />I hope this is of some help and may fit your cir***stances.<br />If not, stay tuned. Someone here is bound to get you on the water!!!!!