Engine Fogging

C

Chas

New Member
Jun 23, 2008
34
Southeast Michigan
Boat Info
280SS Anniversary Edition
Engines
Twin 5.7 260 HP Alpha 1
Can I use a can of the Engine Fogger and squirt it directly into the throttle body of my 1999 5.7 EFI? Someone told me I could on an EFI, but not if I had an MPI. Can anyone verify? Thanks.
 
I was told by very experianced mechanic that if you use fuel stabilizer (Engine store 'easy start and store') and run the engines for 20-30min the fugging becomes unnecessary overkill. I never fugged my EFI on 240DA and didn't do on MPIs on my 320DA either, all was fine.

Alex
 
I guess the question I have is why are you wanting to fog the engine? Are you winterizing already or planning to store it for awhile?
 
General Motors places the port fuel injectors on the floor of the intake manifold. Fogging oil pools on the manifold's floor, runs into the injectors, and turns gummy. That gummy oil protects from corrosion, but also makes the injectors useless. You can use fogging oil if there is no chance that the oil can touch the injectors. If you are not certain, don't fog.

Best regards,
Frank
 
Frank - can you then just fog the individual cylinders? At least you could reduce any potential corrosion - this plus a fresh oil change may be what the OP needs.
 
Sure, just shoot the stuff into the cylinders via the spark plug holes.
 
Search CSR for this topic. Mercruiser has a recommended "cocktail for storing EFI engines that lubricates the cylinders and fuel handling parts without clogging up injectors. It is simple, inexpensive and relatively easy to rig up, but best of all it does protect the engine with out clogging up the injectors.
 
I purchased a GM engine that was 'overly fogged' prior to being shipped. They were fogged though the plug holes. Fuel injectors were ALL useless. I had to buy six new ones. On newer engines, I would follow mercruiser's recommendations (what Frank said!) and wouldn't pour anything into the throttle body or into the spark plug holes. I do know that our dealer cheats a bit by putting the cocktail into the fuel filter rather than swapping fuel lines around. That's the way I do it as well and 4 years - no problems...
(can't we ban winterization questions until later in September??)
 
I was under the impression that products like this should do just fine http://www.boatersworld.com/product/176130474msk.htm

I was also told that fugging cylindars was not necessary if the fluid is run trhough the system for 20-30min.

Frank W., is the product you're refering to something different?

Thx,
Alex.
 
HavingFun said:
I thought adding oil to the fuel filter was an acceptable form of fogging.
Click to expand...
The merc manual indicates a mixture of 2 stroke oil and fuel stabilizer I believe....Not crankcase oil.
 
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I'll check later, but I believe my Merc. Procedures Manual states the following: add x ounces of 2 cycle merc prem. oil to the fuel/water seperator (mine is the spin on oil filter style) and run engine until blue smoke can be seen exiting the exhaust. Alternatively, you could also hook up a six gallon tank using a mixture of gas/2 cycle oil. As Frank stated, try a search.
 
The Mercruiser coctail is a mixture of 2 stroke oil, fuel stabilizer and regular unleaded gasoline. I just haven't had time to look up the proportions yet.

This is not a single over the counter stabilizer but a blend of the 3 components. As I recall from seeing the mechanics winterize a boat last year, the engine will smoke like the dickens, but will still run.
 
The question remains the same, can you spray fogger in an EFI throttle body but not an MPI?
 
Chas,

Good question and I undestand why you are asking due to the location of the injectors.

The Merc. Mtx. Procedures manual (for 1998 Gasoline Alpha Series) has different sections for EFI and Carb. models. Prior to winterizing the engines, the manual recommnends pouring the appropiate amount of fuel stablizer into tank, bring the engine up to operating temp. and then change the engine oil. This is also a good time to change the drive oil and check alignment.

Here is Merc's recommended way of laying up an EFI engine per the Alpha series Mercruiser Mtx. Procedures manual.

Warning:
Avoid Fire or Explosion: Be sure engine compartment is well ventilated and no gasoline vapors are present during the following operation.

Warning:
Avoid Fire or Explosion: Fuel injection system is pressurized during operation. Use care when removing water separating fuel filter. Fuel could spray on hot engine causing fire or explosion. Allow engine to cool down before attempting to remove the water separating fuel filter in the following procedure. Also, hold a clean shop towel over the water separating fuel filter when removing it to help avoid fuel spraying on the engine.

1) Close the fuel shut-off valve, if so equipped. If no fuel shut-off valve is present, a suitable method must be employed to STOP the flow of fuel from the fuel tank to the engine before proceeding.

2) Prepare the fuel system for extended storage as follows:

A Allow engine to cool down.
B Depresss latch and remvoe (slide Down) the lower filter cover.
C Remove the water separataing fuel filter.
D Pour out a small amount of fuel inot a suitable container, then add approximately 2
ounces (60 ml) of Quuicksilver 2-Cycle Outboard Oil to the fuel in the water separting
fuel filter.
E Install water separting fuel filter.
F Start and run at idle speed until the water separating fuel filter and fuel injection
system are empty and engine stops.
G Remove and discard water separating fuel filter.
H Install new filter.

So, this is the answer per the manual. Someone elso on the board may have fogged their EFI engine with fogging oil. I have never tried using fogging oil/spray. The next section goes into draining the water from the cooling system.
 
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Mine are winterized by adding two large Stabil bottles to each tank, 275 gallons total.

The fuel filter is ½ emptied, then topped off w/ motor oil.

The bulkhead electrical fuel valve is disabled by removing one wire.

The spark arrestor is moved away from the manifold.

With the engine running, I spray fogging oil into the manifold until the engine runs out of gas.

In the spring I use the Mercruiser engine tool and the fuel pressure tool to purge air from the system.

It always pops right off w/o problems.
 
Interestingly enough I was told by an authorized Merc dealer/service center yesterday that they spray fogging oil into the throttle body for fogging.........I found this odd.
What about the MAF sensor, etc???
 
My Seloc Manual for a 2004 5.0 MPI dittos the Mercury information provided by SeaRide. ---- 2 oz. in the fuel water separator.
 
I used the merc contaill of 2 stroke oil/fuel stablizer/and gas I also add some "startron" for good messure. I use a remote outboard tank (6 gallon) I disconnect the flare fuel fitting right before the shut of solinoid. The flare fitting is a 1/2" female so i use a 1/2" male on the outboard tank. This is really easy to do. Just be carefull not to over tighten the fittings you will split the female nut. Believe me I've done it. just snug the fittings then check for leaks. This whole procedure is on mercruiser web site (I wish I knew how to include a link to that page) but a little searching and all you answers will be there.
 
ps no mentioned any where I have found about spraying or not spraying into the trottle body. My opion is not to do it if that what merc wanted they would have said it somewhere also it a long way to the cyliders and there are expensive sensative sensors in the way.
 
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