Mercury 115 flooding problem

[shawncs1981]

I have a 1987 115 horse inline six that floods out after i run it for about 15 minutes. I found that the quicksilver autotmatic oil mixers are not that reliable so i unhooked it and it still has the same problem. The only thing is it doesn't completly die it just sounds like it missing but if i take the spark plaugs out and wipe them down it runs fine for a little while. Any sugestions would be much appriciated.

 

[WillyBWright]

Re: Mercury 115 flooding problem

Do any of the sparkplugs have significantly different deposits on them when you clean them off? You are premixing 50:1? I'm wondering of you have a torn fuel pump diaphragm or two (if it has two pumps). That could cause one to four cylinders to flood.

 

[shawncs1981]

Re: Mercury 115 flooding problem

Yeah some are a bit better than others but i think it only has one pump.

 

[roger3645]

Re: Mercury 115 flooding problem

Does this happen when your running WOT? If so, check to see if the carbs are opening too much.

 

[shawncs1981]

Re: Mercury 115 flooding problem

Yes it happens when i am running wide open. How can i check to see if they are opening up to much?

 

[Windykid]

Re: Mercury 115 flooding problem

I think you can take the covers off (not running) and goto WOT and look to see if the butterfly's are past full open.

 

[Clams Canino]

Re: Mercury 115 flooding problem

Put a kit in the fuel pump and clean the carbs with particular attention to the float needles and seats - and your bound to fix the fuel system.

Also, it's just as likely running LOW on fuel as flooding at WOT. Wiping the plugs means little to those - it's the stopping to DO it that causes the change. Try running it at 4000-4200 and see if the problem goes away.
Running WOT for extended periods is "asking for it" - "it" being piston meltage.

-W

 

[OldMercsRule]

Re: Mercury 115 flooding problem

Put a kit in the fuel pump and clean the carbs with particular attention to the float needles and seats - and your bound to fix the fuel system.

Also, it's just as likely running LOW on fuel as flooding at WOT. Wiping the plugs means little to those - it's the stopping to DO it that causes the change. Try running it at 4000-4200 and see if the problem goes away.
Running WOT for extended periods is "asking for it" - "it" being piston meltage.

-W

Wayne, Is that true of all inlines? I have two 1969 1000s and three 115s (a 1978 1150, 1979 115 and a 1981 115). The 1987 115 would be similar to the 140 at the crank I think, (so more fuel flow then my older crank rated motors). How do long do you recommend a WOT run, (which I rarely do for more then 5 to 10 minites until I back off to 4000 + or -)? Thanks, (sorry for the hijack) JR