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Old mercury l6 fuel enrichment mod

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Bill Krummel

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I have been dealing with a 76 merc 1150 the is hard to star for a few weeks since repowering my boat with it and have been doing alot of reading on the subject. Most of what i have read points to doing a fuel enrichment system using a solinoid from a newer engine and plumbing it into the crankcase near the carbs. My question is for anyone who knows about this mod, i plan to plum it into the crank ports in the middle. How will the cylinders above it get fuel? The solinoid i have uses 1/4 line so theres not going to be a ton of fuel flow so i think it will mostly travel to the lower cylinders.
 
The primer solenoid on Johnson / Evinrude outboards is a wonderful alternative.-----It is a good unit.----Used on 9.9 HP to 300HP.---Used from about 1980 to 2007 or so.----Lots of them out there used.-----An easy install on a Mercury in my opinion.
 
the solenoid i have does the same thing, although i like the manual override option on the Johnson. my main question is where is the best place to inject the extra fuel on the motor?i found a video of a guy putting it into what looks like vacuum lines next to the carburetors but im not sure that the fuel will reach any cylinders above wher the en richer T's in.
 
For the OMC primer on a MERCURY motor I install the nipples right on the bypass covers.---Top 4 cylinders only is sufficient.------Right there as incoming charge goes through the intake ports.-----Motors start near instantly !!
 
racerone said:
For the OMC primer on a MERCURY motor I install the nipples right on the bypass covers.---Top 4 cylinders only is sufficient.------Right there as incoming charge goes through the intake ports.-----Motors start near instantly !!
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Hello racerone I am also interested in putting the johnson electric primer valve on a 76 1150 115hp in-line 6cyl merc but can't seem to find any diagram or video on it. Are the spots already there on the merc or will I need to drill and tap it?
 
I installed 4 salvaged nipples on the bypass cover for cylinder 1 , 2 , 3 , 4-----Easy to make nipples using small screws with a 0.015" hole in them.---Use part # for a TEE in the small hoses.-----Fuel feed to the primer comes from a TEE from fuel pump supply to carburetors.
 
racerone said:
I installed 4 salvaged nipples on the bypass cover for cylinder 1 , 2 , 3 , 4-----Easy to make nipples using small screws with a 0.015" hole in them.---Use part # for a TEE in the small hoses.-----Fuel feed to the primer comes from a TEE from fuel pump supply to carburetors.
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Ok thank you that's awesome I have had this old girl since 05 and it's been pretty hard starting since day one but the only one I've ever needed. It also came with a fuel pump that evidently isn't OE it has a square one but it's supposed to have a 66530A2 I'm gonna get a used one and a rebuild kit it started burning a lot of gas like 12gal in 4hrs. Anyway thank you very much for your reply.
 
??---12 gallons in 4 hrs at idle or full throttle ?----Newer motors may have used a different pump and I do not believe that is your issue.
 
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racerone said:
??---12 gallons in 4 hrs at idle or full throttle ?----Newer motors may have used a different pump and I do not believe that is your issue.
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Ok actually it happened twice both times while trolling last year and the back of my boat was black and oily like unburned fuel or something. Just replaced cdi part number 114-2986 it's the ignition pack, cap, plugs and wires, and new engine side wire harness. Never did get a chance to figure it out. Would absolutely take any and all advice. Was gonna start with checking the spark and timing and fuel pump.
 
cattrapper091 said:
Ok actually it happened twice both times while trolling last year and the back of my boat was black and oily like unburned fuel or something. Just replaced cdi part number 114-2986 it's the ignition pack, cap, plugs and wires, and new engine side wire harness. Never did get a chance to figure it out. Would absolutely take any and all advice. Was gonna start with checking the spark and timing and fuel pump.
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I could hear the motor change the sound of how it was running and then it burned the whole tank of gas twice and the oily black crap on the back
 
racerone said:
Post the actual compression values here.----Do you install a new impeller every 5 years ?
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Haven't had it done in a couple years it was 118 no more than 3 or 4psi difference between them. Impeller at the same time try and do it every 3 years. I can't find my paper with exact numbers. What you thinkin.
 
racerone said:
Any time a motor is acting up , I start with a compression test.
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Ok I will definitely check that I was wondering if something happened to the ignition pack or coil maybe the rectifier since it started the problem when I heard it change? Thank you for your insight I have a tester so I will start there.
 
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