mercury 9.8 will not top out

river mac

Recruit
Joined
Jun 29, 2012
Messages
4
Hey all,
I have a 1971 mercury 9.8 model 110. I received this from an old friend who had it stored in the corner of an old shed. He had not used it in over 15 years. I got the thing started seamed to run well at low rpms and even idles in gear. After it warms up it has decent hole shot but misfires at 3/4 throddle. I say misfires but more seams to be lack of fuel. I have cleaned carb,checked fuel pump, new plugs, put thread sealant on all fuel fittings, no improvement. I did notice a crack on one of the coils but I am hesitant to replace a coil just to troubleshoot especailly with cost of $80. Will a coil fail at high demand? In addition are there replacement coils for this model that are less pricey I have heard that some car coils are very much the same thing is this true?
Does anybody have any ideas? I am planning on this be simply a back up motor but would love to get it running well.
 

oldman570

Lieutenant Commander
Joined
Mar 25, 2011
Messages
1,615
Re: mercury 9.8 will not top out

The coil could be the trouble but it could be a wire arching accross as the throtal is advancing the stator plate or the ground wire on the back of the coil not making good contact. If the wires from under the stator plate, going to the coils, are brittle and the insulation is falling off they will probbly need to be replaced if you have not done them already. They can be replaced without changing nor moving the points as they can be a Bit== to get set correctly again. JMO
Oldman570
 

river mac

Recruit
Joined
Jun 29, 2012
Messages
4
Re: mercury 9.8 will not top out

Thanks Oldman570,
I have noticed some crumbling wires as well as some quick fixes such as wire nuts on coil ground wire. I am ready for the thaw to get it in the Mississippi! I am also from Northern IL. Thanks for the help.
 

oldman570

Lieutenant Commander
Joined
Mar 25, 2011
Messages
1,615
Re: mercury 9.8 will not top out

Check you PM's under notiacations at top of page.
Oldman570
 
Top