"Fogging" new VP 4.3?

harringtondav

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My owners manual says to mix two stoke engine oil into my boat's fuel and run it through to get the necessary corrosion protection over winter lay up.
With my previous Merc carbed 4.3 I simply sprayed fogging oil into the carb.
My VP 4.3 is high tech with high pressure direct injection, O2 sensors etc. Is there a reason I shouldn't simply spray fogging oil into the intake/throttle body? This is a non-CAT engine.
If I can't fog the engine, what is the recommended premix ratio of the two stroke oil?
(if i premix things will be smokey for some time next spring. ....got a fair amount of fuel in the tank)
 

Lou C

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The issue with these is that even if its a non cat engine the sensors in the intake tract can be damaged by fogging. I would look and see what Mercury says if Volvo does not give an exact %age of 2 stroke fuel. On my old 4.3 with the Quadrajet 4bbl I get two cans of fogging oil and go to town!
 

harringtondav

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The issue with these is that even if its a non cat engine the sensors in the intake tract can be damaged by fogging. I would look and see what Mercury says if Volvo does not give an exact %age of 2 stroke fuel. On my old 4.3 with the Quadrajet 4bbl I get two cans of fogging oil and go to town!
I could access the spark plugs fairly easily on my Merc 4.3, and occasionally gave each cyl a shot through the hole, and crank it with the dead man switch tripped. One side of the new engine is accessible. Not sure about the starboard side. ...could take more excavation than I want to do.
 

Scott06

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My owners manual says to mix two stoke engine oil into my boat's fuel and run it through to get the necessary corrosion protection over winter lay up.
With my previous Merc carbed 4.3 I simply sprayed fogging oil into the carb.
My VP 4.3 is high tech with high pressure direct injection, O2 sensors etc. Is there a reason I shouldn't simply spray fogging oil into the intake/throttle body? This is a non-CAT engine.
If I can't fog the engine, what is the recommended premix ratio of the two stroke oil?
(if i premix things will be smokey for some time next spring. ....got a fair amount of fuel in the tank)
I think some folks mix the two stroke and fuel pour it into fuel filter when changing, run it a few seconds. to get oil gas mix in engine.
come spring the small amount in the filter is quickly burned off during start up
 

harringtondav

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I think some folks mix the two stroke and fuel pour it into fuel filter when changing, run it a few seconds. to get oil gas mix in engine.
come spring the small amount in the filter is quickly burned off during start up
Thanks much! This will work.
...I've got plenty of 50:1 made up for my Husqy yard tools. ..recon that mix should be good.
 

BRICH1260

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Like said above, I simply pour an ounce or so of two cycle oil into my fuel filter when replacing it, run it for a few minutes, good to go. Do not spray fogging oil into the throttle body.
 

harringtondav

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Like said above, I simply pour an ounce or so of two cycle oil into my fuel filter when replacing it, run it for a few minutes, good to go. Do not spray fogging oil into the throttle body.
Also thanks.
Goal is to get the 2 stroke oil in the engine and pink antifreeze into the sea water side of the closed cooling system. ....at the same time.
First winter learning curve.
 

Barney22

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My owners manual says to mix two stoke engine oil into my boat's fuel and run it through to get the necessary corrosion protection over winter lay up.
With my previous Merc carbed 4.3 I simply sprayed fogging oil into the carb.
My VP 4.3 is high tech with high pressure direct injection, O2 sensors etc. Is there a reason I shouldn't simply spray fogging oil into the intake/throttle body? This is a non-CAT engine.
If I can't fog the engine, what is the recommended premix ratio of the two stroke oil?
(if i premix things will be smokey for some time next spring. ....got a fair amount of fuel in the tank)
Well, I have the same engine and same question. Does anyone know if a current non catalyst Volvo-Penta 4.3 engine can be safely fogged ?
Thanks Barney
 

saaristo

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How I do my 4.3gxi-jF is that I pull the plugs, spray fogging oil for couple of seconds into cylinders and then either turn it couple rounds by hand or with starter (plugs not fitted) and thats the end of it. No two stroke oils into fuel or anything (I run non-ethanol fuel only). Drain the sea water side meaning the intake hose, exchanger and exhaust manifolds and thats it.
 

harringtondav

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Well, I have the same engine and same question. Does anyone know if a current non catalyst Volvo-Penta 4.3 engine can be safely fogged ?
Thanks Barney
Above threads say to not fog. My owners manual said to put premix two cycle in the tank and run the engine.
Others above said to drain the fuel filter and fill it with a rich premix ratio.
I started to do this yesterday, but couldn't get a band filter wrench on the filter. Very little clearance. So I enriched a gallon of 30:1 with a few more ounces of oil and put it into the tank with the Stabil and gas.
....no idea of the final ratio but I had light smoke from the exhaust so I said good enough.
...then I remembered I have a fabric "tourniquet" filter wrench that probably would have worked. Next year.
 

Lou C

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My brother has a 2020 Chapparal with the new Merc 4.5 that he’s going to ask me to help him winterize. So I’ll have to figure this out in a few weeks. My initial thought is to measure how much gas a standard Merc fuel filter holds and then just mix in the correct amount of 2 cycle oil.
 

saaristo

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Since I'm only spraying the cylinders but all others are mixing fuel I'm starting to think whether I might be missing something. So could someone say what other than cylinder walls will benefit from two stroke fuel mix?
 

Lou C

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Coating intake valves/exhaust valves with oil so they don’t get surface rust in storage. Just like the outside of the engine gets condensation so does the inside….
 

Nashville

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Well, I have the same engine and same question. Does anyone know if a current non catalyst Volvo-Penta 4.3 engine can be safely fogged ?
Thanks Barney
If the motor is the exact save as the OP, a VP V6-250-O, yes. Page No. 90 of the Operator’s Manual for this motor (VP Publication No. 47712778).
 

harringtondav

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If the motor is the exact save as the OP, a VP V6-250-O, yes. Page No. 90 of the Operator’s Manual for this motor (VP Publication No. 47712778).
...hmm. OP here. My manual is back at our river place. I'll check p.90. Apparently I missed this.
 

harringtondav

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If the motor is the exact save as the OP, a VP V6-250-O, yes. Page No. 90 of the Operator’s Manual for this motor (VP Publication No. 47712778).
I checked the online copy of this manual.
P. 90 doesn't address fogging. It does describe the two cycle oil process.
"During storage the engine’s internal components must
be protected from corrosion. This is done by
introducing a Fuel Storage Mixture in to the engine.
Fuel treatment and two-cycle motor oil are mixed in
gasoline and then run through the engine. The oil in
the mixture coats the inside of the engine"
 

muc

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Will allow you a free download of the Service and Maintenance manual. In it will be covered how to use a separate tank to get the correct mixture into your motor.

@harringtondav your engine hasn't been registered in your name and has an open recall on the engine. Highly suggest you contact the selling dealer and get both of these things taken care of.

Getting the CORRECT mixture through the fuel system is important in all boats, but critical in these newer systems. The oil coats and protects the pumps and injectors. (helps with carbs to) We are finding this is very important. All the manufacturers are looking at the components very closely during warranty repairs and declining coverage when proper maintenance hasn't been performed.

You must start with an empty fuel filter when doing this. Fuel doesn't flow from one end to the other, it mixes with what's already in the filter. So starting with a full filter or just adding oil to a filter won't work properly.
 

Nashville

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I checked the online copy of this manual.
P. 90 doesn't address fogging. It does describe the two cycle oil process.
"During storage the engine’s internal components must
be protected from corrosion. This is done by
introducing a Fuel Storage Mixture in to the engine.
Fuel treatment and two-cycle motor oil are mixed in
gasoline and then run through the engine. The oil in
the mixture coats the inside of the engine"
The correct procedure for this engine is Page No. 90. This is how the internals are protected.
 

harringtondav

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May 26, 2018
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2,438
Will allow you a free download of the Service and Maintenance manual. In it will be covered how to use a separate tank to get the correct mixture into your motor.

@harringtondav your engine hasn't been registered in your name and has an open recall on the engine. Highly suggest you contact the selling dealer and get both of these things taken care of.

Getting the CORRECT mixture through the fuel system is important in all boats, but critical in these newer systems. The oil coats and protects the pumps and injectors. (helps with carbs to) We are finding this is very important. All the manufacturers are looking at the components very closely during warranty repairs and declining coverage when proper maintenance hasn't been performed.

You must start with an empty fuel filter when doing this. Fuel doesn't flow from one end to the other, it mixes with what's already in the filter. So starting with a full filter or just adding oil to a filter won't work properly.
Thanks for the info Muc. I've been to this site many times, but didn't scroll down far enough to see the free manual. ..also need to poke the dealer....again.
I now have a copy of the manual.
I think I understand why fogging won't work. High pressure direct fuel injection needs oil in the fuel system. This won't happen through the throttle body.
 
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