how to install OMC electric priming system on 1977 1150?

tavacska

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I am trying to install an electric priming system on my 1977 1150 inline 6, as recommended by most guys to erase the cold starting issue forever.

I would like to use the choke button and power button for the electric primer, and only for the priming purpose.

Anyone has experience on this? Which product should I take a look? Any recommendation?
Where should I put this electric primer on? In-line with the mechanic primer? Or by-pass the fuel pump of engine?

Actually, if there is a video on this that will be great.

Thanks.
 

racerone

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I am going to be blunt here.----You look at and understand how these primers or enrichers work.----I have installed the OMC primer on an inline Mercury and it worked like a charm.----Note,---- these units are valves and they DO NOT PUMP fuel into the motor.
 

tavacska

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I am going to be blunt here.----You look at and understand how these primers or enrichers work.----I have installed the OMC primer on an inline Mercury and it worked like a charm.----Note,---- these units are valves and they DO NOT PUMP fuel into the motor.

Thanks, racer,

Do you have a link of the product that you installed?
 

roscoe

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Ok, I have to ask, what is the difference between an OMC enrichment valve, and a Mercury enrichment valve?

And why not use the Merc version?
 

racerone

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OMC primer uses fuel delivered by the fuel pump and when valve opens , that fuel is pushed into the wee hoses.------The Mercury enricher uses fuel from carburetor bowl and that fuel is NOT under pressure.
 

Chris1956

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Also, I think the Merc carbs that use the enrichment system are different than what the OP has.

Gee, I never had that much difficulty starting my '77 Merc 1500. The choke plates need to close, the engine needs to crank at a good rate, and 3 sec later, vroom vroom. Not sure why an enrichment system is needed.
 

roscoe

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OMC primer uses fuel delivered by the fuel pump and when valve opens , that fuel is pushed into the wee hoses.------The Mercury enricher uses fuel from carburetor bowl and that fuel is NOT under pressure.

thanks
 

tavacska

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1. Is this the item I should use as the OMC Fuel Primer Choke Solenoid?
electricPrimer.JPG

2. For the installation,
1) the in-let connection will come from the split from the section between the fuel pump and carburetor reservoir cup.
2) the out-let connection will go to the carburetor section as I marked in the following picture.

Is this right?

carburator.JPG
 

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racerone

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That is the item.-----Should be easy to find used.-----Use the wire that now goes to the Mercury solenoid to activate it.-----Tees into the line from pump to carburetors to get fuel at pressure.----The wee hoses can be fed to nipples that you install on carburetor throat or at bypass covers.---All easy to do.
 

tavacska

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That is the item.-----Should be easy to find used.-----Use the wire that now goes to the Mercury solenoid to activate it.-----Tees into the line from pump to carburetors to get fuel at pressure.----The wee hoses can be fed to nipples that you install on carburetor throat or at bypass covers.---All easy to do.

Thanks, racerone.

I am still a little confused about the 1. nipples that you install on carburetor throat or 2.bypass covers
Are those as pointed in the following pic?

And one more question, the wee hose is installed to the first carburetor or all the three carburetors? carburator2.JPG
 

444

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Also, I think the Merc carbs that use the enrichment system are different than what the OP has.

Gee, I never had that much difficulty starting my '77 Merc 1500. The choke plates need to close, the engine needs to crank at a good rate, and 3 sec later, vroom vroom. Not sure why an enrichment system is needed.

Curious about this as well. I have a 78 Merc 175 v6 and all I do is throttle full forward in neutral, squeeze primer bulb until hard then hold choke button while cranking until she fires. I had to make a new linkage rod for the choke solenoid because a piece was broken when I bought the boat but after that it starts fine. A bit of cranking when cold but nothing outrageous. How do those 1500's behave?
 

tavacska

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Also, I think the Merc carbs that use the enrichment system are different than what the OP has.

Gee, I never had that much difficulty starting my '77 Merc 1500. The choke plates need to close, the engine needs to crank at a good rate, and 3 sec later, vroom vroom. Not sure why an enrichment system is needed.

Mine starts within 10 sec cranking with fresh fuel. But I have to press primer very hard, and open throttle in neutral, and press the choke button all the time. And I have to set idle mix to 3 1/2, in which I already see a lot black soot on the spark plugs. The manual recommends 2 1/2, which is also fine for my idle running. However, with 2 1/2, that means 20-50 sec cranking for cold start.

My guess is for its age, there must be leak of air somewhere in the engine, or the reed valve aging problem, which results in less sucking power on start.

That's the reason of asking help of enrich solenoid. In that case, I wish I can set the idle mix to 2 1/2.
 

Chris1956

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Idle mixture settings need to be set to allow good acceleration, and reasonable idle. They will normally be a bit richer than 1-1/2 turns open.

I would suggest OP double check carb float adjustment and link and synch.
 

Scaaty

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Click photo a few times to enlarge...self explanatory on hook up...
 

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tavacska

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Idle mixture settings need to be set to allow good acceleration, and reasonable idle. They will normally be a bit richer than 1-1/2 turns open.

I would suggest OP double check carb float adjustment and link and synch.

I rebuilt the carb with kits, but not for the floats.
I set up the seat, needle to specifications. From last time clean up 5 months ago, I told myself not to do the carb again, except that I have some solid proof that it is the carb's problem.
 

tavacska

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Click photo a few times to enlarge...self explanatory on hook up...

Thanks. Just happen to find that diagram too.
I also find the enrich system in the mercury manual too. That manual includes different years of engine, so I never tried to look through those pages.
 
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