'76 850 Trigger / Stator Issues - I need some input

mlbinseattle

Petty Officer 2nd Class
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Aug 1, 2015
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Flooding is another 4 stroke worry, when you enrich all you are doing is pumping gas into the crankcase, you almost have to flood em to start em, once you get everything close it will run, even sorta close and it will run, look at mine I had so much water, crud and things in the carb bowls and in the carbs and it ran, get everything close then fine tune.

Thanks, I'll remember that tip about the enrichment valve and not worrying about flooding it.

What are your thoughts about the fair amount of water getting spewed out of the exhaust at the exhaust plate and the plugs showing no sign of water washing?
 

Bill kubiak

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Jan 31, 2004
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629
I am confused, there should be no water spewing out the exhaust plate. Almost all the water comes out thru the prop hub
I think you are overthinking things and water washing the plugs, I thought you changed all those gaskets
 

mlbinseattle

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I am confused, there should be no water spewing out the exhaust plate. Almost all the water comes out thru the prop hub
I think you are overthinking things and water washing the plugs, I thought you changed all those gaskets

That's the one thing I didn't do. I didn't pull the exhaust cover because I was tired of drilling/tapping holes for the cylinder cover. I figured I'd take my chances with the exhaust and hope no water was getting into the exhaust from the inner water jacket. Also, the plugs are not getting water washed. I'm just seeing a fair amount water spewed from the exhaust at the exhaust extension ports that are in the rear of the lower unit directly underneath the lower cowl. The water has to be coming from somewhere.
 

mlbinseattle

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To clarify, the plugs look like they're getting used. They don't look clean like they've never been used. I'm seeing what I believe is a drop of residual oil on the sides when pulled out, but possibly that's some water? I'm not sure, now. I'll probably take a pic to show what I'm talking about.
 

Chris1956

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Mar 25, 2004
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When you say water out of the exhaust plate, you mean the square holes at the base of the powerhead? If so, those are exhaust relief openings, and water out of there is normal. If the plugs are dirty, there is likely no water infiltration, so leave the exhaust covers alone.

That motor does not have an enrichment valve. It has two choke plates. Newer Mercs have an enrichment valve, which is a solenoid-type valve which allows raw fuel to enter the carb throats. On an inline motor, fuel from the top carb drips into the lower carbs.
 

Faztbullet

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Mar 2, 2008
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15,931
Wheew...No wonder your confused with so much incorrect info. First get rid of the Selco manual and get a factory manual, 2nd the MAX timing has NOT changed on the ADI ignition motors so set it back to 27 degrees, 3rd your motor has a enricher circuit on carb, no enrichener valve or choke plates. Make sure when choke is engaged that both levers on carb are fully pulled shut as this shuts off air to idle circuit causing a overrich condition to start.
 

mlbinseattle

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Aug 1, 2015
Messages
100
When you say water out of the exhaust plate, you mean the square holes at the base of the powerhead? If so, those are exhaust relief openings, and water out of there is normal. If the plugs are dirty, there is likely no water infiltration, so leave the exhaust covers alone.

Yes, that's the place.

This morning, I ran it for a few minutes. Then, like always, it starts up with the miss after about 5+ minutes. It's a hard miss, like it's only running on 2 or 3 cylinders. It'll last a few seconds, stop, and then start again. Eventually, it'll stop running altogether.

I pulled the plugs and looked at those, again. #3 and #4 look cleaner than #1 or #2. 3 and 4 didn't appear to have any oil on them like 1 and 2 did. Again, once started, it runs okay for about the first 5 minutes, then it starts up with the hard miss.

Got to looking at the exhaust cover, and it looks scorched (the paint) in the area where #3 exhaust is located. Also, while running, I noticed that water was being squeezed out of the exhaust cover in the rear about midway. I posted a link to a YouTube video that I uploaded, and where I have my finger is where it's happening. I panned over to the spark plugs to show how far up the exhaust plate gasket that it's happening.

My thoughts are this: If the exhaust plate gasket is leaking like this, then chances are the inner water jacket cover gasket is probably worse, and water is making it's way into #3 and #4 cylinders (I'm thinking more 3 than 4) through the exhaust ports.

One other thing: While this hard miss is happening, I've had the timing light on each plug wire. The flash is steady and strong for each plug. Personally, I believe it's taking 5 minutes or so after the 1st startup for the water to get to the level where it's affecting the 3 and 4 cylinders.

Tell me I'm wrong, but I have a feeling that I'll be pulling that exhaust cover in short order.
 
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