dead cylinder

[simon38]

1999 40hp 4stroke mariner 3cyl. it has been sitting for 8 months.bottom cyl. is dead. is getting fire,fuel and compression but still does not work.took carbs off and cleaned the bottom one.operated the linkage and was getting fuel out of all 3. pulled spark plug wire off and was getting fire installed compression gauge and was getting 120lbs on each cylinder swapped no.1 and no.3 coils around to see if i had a weak coil made no difference i have already replaced all 3 spark plugs. maybe a valve out of adjustment?

 

[Solittle]

Re: dead cylinder

It would help if you provided a bit more detail on how you determined that it was getting fuel, spark and what the compression readings were.

 

[wayne h]

Re: dead cylinder

it cant have all 3 or it would be running somthing is not right in 1 of them 3 things

 

[iRich]

Re: dead cylinder

try some new plugs?<br />Rich

 

[DJ]

Re: dead cylinder

I agree with IRich.<br /><br />Actually, a plug can fool you. It will spark, with no load, and die when put back in the cylinder head.

 

[Valv]

Re: dead cylinder

I agree with plug too. I had a 1984 150hp that did same with brand new (cheap Champion...) plugs.<br />It scared the heck out of me, after 1/2 day trying everything I installed plugs incorrectly (the not working one on anothey cyl) and find out 1 of them was bad, even if brand new....<br />Talking about being mad....at Champion. Now I use only NGK.