Help with my 500 no fire

Joined
Jul 13, 2003
Messages
7
Hello,<br />I have a Mercury 500, 1976 4 cyl outboard, it has the type "V" ignition system,one coil per cyl. The thing ran like a champ until last year. It developed a hole in the exaust baffel plate. I put a new plate and gaskets. After assembling everything she cranks around but doesn't start. There is no spark at any plug.<br />What is the procedure that I should follow?<br />The wiring looks a little scary with age. The previous owner went liquid neoprene all over them due to cracking and chipping insulation.I could replace all the wires, it looks easy and I have the diagrams.<br /> I just want to know if there is a methodical checklist that I should follow to find the problem.<br /> I live for the first time in my life less than 2 miles to the sea and it is killing me to not be able to get out. I love this motor and want to get it doing its thing again.<br />Thanks,<br />Damon
 

dolluper

Captain
Joined
Jul 19, 2004
Messages
3,904
Re: Help with my 500 no fire

check your switch box ground first,then do a stator test, then trigger test and a coil test ,the recitifer all after your spark plugs ,any visiable breaks in wiring ,bad GROUNDS
 

Chinewalker

Fleet Admiral
Joined
Aug 19, 2001
Messages
8,902
Re: Help with my 500 no fire

Hi Damon,<br /> If you suspect the wiring, you can make up a few temporary jumper wires with some alligator clips. If you suspect a wire that may not be making complete circuit, you can use the jumper wires to try and complete the path. You might find that a ground wire isn't grounding, or perhaps some other wire isn't doing its job. Does your motor have a mercury switch on the side of the exhasut plate? If so, there may be a problem with that, as you must have removed it to do the baffle plate. You can remove the mercury switch from the circuit entirely by jumping around it...<br /> If you can localize the bad wire, then you know it's possible to replace all of the iffy wires and still have it work when you're done. As it is now, you may go through the trouble of splicing in new wires, only to find a trigger or switchbox is bad.<br />- Scott
 
Joined
Jul 13, 2003
Messages
7
Re: Help with my 500 no fire

Thank you fellas,<br />I'm going to get into it ASAP.<br />I already went around the mercury switch as I suspected it because the wire leading into it broke! Not the problem.<br />Is there any way to get the flywheel off without the 80.00 flywheel puller tool?<br />Damon
 

dolluper

Captain
Joined
Jul 19, 2004
Messages
3,904
Re: Help with my 500 no fire

1and half inch pipe fine thread 16tpi and flat metal drill hole weld nut at hole ,long bolt through nut ,to test your stator trigger you don,t have to pull the fly do it from your switchbox----look under post mercury 175 rx2 sportjet lift ring [robert lawrie] KCLOST has a neat idea pulling and lifting
 
Top