1985 115 hp mercury 6 cyl wont start

[1985merc]

Hi guys new to this... I recently bought a 1985 115 hp mercury 6 cyl (6480195) 3 carbs (side bowl type wmk411a) of course it does not start.

It will turn over however (i know not good to do) I did spray some starter fluid into the carbs and it fired right up and then died.

I checked fuel lines and getting fuel to carbs and choke is ok (enricher valve).

I did take off and tear down carbs (carb #1 float was stuck) a spray down with carb cleaner jets ect... seemed good however tried to start...same problem (sprayed starter into carbs again, started and died)

Seems that gaskets on side bowls are no good. So i have ordered 3 carb kits and a fuel pump kit and will do a solid cleaning this time (lol from this site)

My question is since does fire up by using starter fluid and dies (Ill switch to mixed gas now for that test) Im assuming its not spark or compression... I just putting this out there in case missing anything... i will be doing a comp and spark test just to check out.... If you guys are out there thanks for any help.

 

[jeffdjpeat]

Re: 1985 115 hp mercury 6 cyl wont start

sounds like a fuel delivery issue to me, get those carbs cleaned, and all set up, ensure the fuel pump works, and that the filter is clean, and try again. just because it fires doesnt mean it is firing on all cylinders tho. make sure you do check spark and compression on all cylinders.

 

[1985merc]

Re: 1985 115 hp mercury 6 cyl wont start

Thanks for the response! The carb kits and fuel pump kit should be here Monday (tomorrow) along with the compression gauge...

When I bought this boat (1st boat) I failed to educate myself on the motor (doing compression test) however over the last 3 days in waiting for parts I got the Seloc manual and did intensive reading throughout and of course reading these forums were a ton of help.

Hopefully the compression checks out. Or Ill really be putting that manual to work this winter.

 

[1985merc]

1985 115 hp mercury 6 cyl wont start. Need pro help

1985 115 hp mercury 6 cyl wont start. Need pro help

Cleaned carbs ..still no start ...

I believe getting weak spark (inline tester) on 1,2,3 cyl and stronger on 5 however 4 and 6 have no spark

Tested stator: checks out

Tested trigger per manual: Confused on this.. however here are the readings
1.249
1.214
1.250

I don't understand how to test the coils, the book is not clear to me .?. Any help would be appreciated... Thanks

 

[bmbecker]

Re: 1985 115 hp mercury 6 cyl wont start

something you might try to test your coils would be to just switch one that is known to be good with one that is not firing. If the problem chases the coil...replace it, if it does not chase the coil, work back from there. I have the exact same problem with mine...same cylinders actually (4&6) and I found it to be something to do with the power packs. But, that coil test should help you out in eliminating the coils as being the problem or identify it.

GOOD LUCK...

 

[1985merc]

Re: 1985 115 hp mercury 6 cyl wont start

It starts and runs I metered the stator and trigger checked out.. switched power wires on switch box...showed bottom switch box was bad...

Picked up a used one and it fired right up...Now to adjust carbs (rebuilt) lol and maybe lake test later on..... Thanks for all the help this forum is great! Ill keep updated as hopefully it works under load... Thanks again!!!!