1986 merc.in line 6 spark problem 90hp

Edison

Cadet
Joined
Oct 22, 2007
Messages
22
Im only getting spark on number 2 and 6 cylinders all the others are dead no spark. any ideas?
 

MercFan

Petty Officer 1st Class
Joined
Dec 31, 2005
Messages
347
Re: 1986 merc.in line 6 spark problem 90hp

Continuity test from inside of distributer cap to plug end?
 

Laddies

Banned
Joined
Sep 10, 2004
Messages
12,218
Re: 1986 merc.in line 6 spark problem 90hp

First remove the black/yellow wire from the switch box and test for spark, then unhook the 2 yellow wires at the rectifier and ck spark, next remove the bios wire beween the switch boxes if none of this helps get back and we can give you test data
 

Edison

Cadet
Joined
Oct 22, 2007
Messages
22
Re: 1986 merc.in line 6 spark problem 90hp

First remove the black/yellow wire from the switch box and test for spark, then unhook the 2 yellow wires at the rectifier and ck spark, next remove the bios wire beween the switch boxes if none of this helps get back and we can give you test data
Laddies, seems like you know alot about these old engines ,Im just getting into trying to learn how engines realy work Im a pump mech. and I don't have much electrical experence but I do have a clymers shop manual.I have been loking at this sight and reading all through my manual Ive also went through all my carbs pointlessly and the fule pump thinking I had a fule problem like gummed up idle tubes or something cuz it was real hard to start an it wouldn't idle at no wake speed for long with out killing but it would fine at higher rpms. Insted of checking for a good spark first I went strait to the fule system LEARN FROM YOUR MISSTAKES RIGHT it an't ez getting them carbs out. I have finely checked for spark and Im only getting it on two cyl.s I used starting fluid to get it started but is that happening ? It seems to me that the triger,stator,recifiter,switch box or coils witch ever has the problem are funchining properly at higher rpms.Is it posible Im starting on two cylinders ? OK now Ive read your reply but its not clear if I need to turn the engine over to check for spark and after I disconect the black/yellow wire and check for spark what if there is a spark do I reconect and go to step 2 ? or leave it disconected THIS IS ALL NEW TO ME
 

Edison

Cadet
Joined
Oct 22, 2007
Messages
22
Re: 1986 merc.in line 6 spark problem 90hp

and how do I check for spark at the wires???:confused:
 

MercFan

Petty Officer 1st Class
Joined
Dec 31, 2005
Messages
347
Re: 1986 merc.in line 6 spark problem 90hp

He meant check for spark at the spark plugs after removing/disconnecting the wires he spoke about.
 
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