Sea Foam in EFI engine

[basstender10.6]

I have a 2000 Mercury 175 EFI 2 stroke engine that I want to use seafoam on. What would be the best way to do it; through the intake, or directly into the cylinders? I took the cowling off my motor yesterday and don't know what I have to remove to get to the intake...I have never done this before so any help would be great.

 

[ondarvr]

If you are worried about it read the manual and use the Merc products they recommend and in the way they describe.

 

[tpenfield]

I made a 50/50 gasoline & seafoam mix and drew it into the engine through the regular fuel line.

 

[UncleWillie]

I made a 50/50 gasoline & seafoam mix and drew it into the engine through the regular fuel line.

+1
Why do you think it needs treating?
Pouring it down the throat will do nothing for cleaning the fuel pump, and especially not the Fuel Injectors.

 

[Silvertip]

How you use SeaFoam depends on what you want to accomplish. If you are using it as a preventive measure, add it to the fuel and you are done. If you are wanting to attempt a carbon removal process, do the same thing and over time carbon will disappear. Or, draw it in the a vacuum line on the engine. Do not spray it in through the intake as the sensors may not like it. A vacuum line would be farther downstream in the intake and would avoid the sensors. My suggestion is to simply wait until you have about 1/4 tank of fuel, then add a couple cans of SeaFoam and then make some high speed runs to heat of the engine and blow out the crude. Repeated use of recommended amounts of SeaFoam will negate the need to do a decarb and it keeps injectors clean.

 

[basstender10.6]

The motor has never been decarboned so I want to clean it out for the first time. Should I just wait till I am low on gas and then pour some into the tank?

 

[tpenfield]

http://forums.iboats.com/forum/engin...ser-7-4-lx-mpi

This link may help, as I've been there, done that with my 2 Merc 7.4 MPI engines. I also used water to decarb after getting some minor results with sea foam. It may have been the combination of the 2 attempts that produced the results, not sure.

There is still a fair amount of carbon build up in my engine, since I tend to idle a bit and the engines have 800+ hours on them.

I had a bad set of cylinder leak tests that prompted me to try the decarb. . . here are the results after the water decarb.

 

[Outsider]

Pretty sure pouring anything into the intake will create problems you probably don't yet have. The best carbon remedy is prevention, but I guess that's not an option now. Try the link below, I did it on a Suzuki 2-banger and we didn't have a mosquito problem for a month. Don't know how much it helped anything, but it hurt nothing, either ... http://www.thehulltruth.com/boating-forum/149269-dunks-decarb-method.html#b

 

[Faztbullet]

. My suggestion is to simply wait until you have about 1/4 tank of fuel, then add a couple cans of SeaFoam and then make some high speed runs to heat of the engine and blow out the crude

Do not do this as you will do more than blow crude out, you will blow engine up!!! Never use Seafoam in concentrated amounts in a EFI engine as it will damage the fuel filters(despite what they say on can) and never run any motor WOT with concentrate as Seafoam as it does not have enough lubricity for this. You will be better off to use the Merc Quikleen for it...

 

[basstender10.6]

I see that people have very mixed opinions on what is the best method for seafoaming an engine. Still undecided for what I should do..

 

[Silvertip]

1) Four stroke engines don't need SeaFoam treatment to begin with unless it happens to be an oil burner or perhaps sees extremely long periods of idle or low speed operation. Again, regular use of a decarb agent at recommended levels can help control this.
2) Carbon is an inert substance and very stubborn to remove so use of a product like SeaFoam in even very heavy concentrations is simply not an issue. The OP has a 175 HP engine which I will gather is sucking fuel from a 30 gallon tank or larger. Two cans of SeaFoam in 8 gallons is not a heavy concentration. On a percentage basis my small engines should have blown up long ago as they periodically get treated to heavy concentrations. My truck with 134,00 on the clock and my car with 105,00 have a regular diet of the stuff. Not for carbon removal but for fuel system cleanliness. Keep a clean fuel system and you will likely have less of a carbon problem. I've seen engines blown for lots of reasons, but never for use of a decarb agent in any concentration. That doesn't mean it hasn't happened, but then one never gets the full story either. Sort of like blaming ethanol for the worlds ills. I guess you either believe in the stuff or you don't. The OP wanted an opinion and he got mine. One takes it or leaves it. I'm a believer and have used the stuff religiously since Hector was a pup.

 

[Faztbullet]

I have seen what Seafoam does to filters in EFI and can count on both hand engines that failed running heavy dose at WOT, the top/bottom bearings give up due to lube failure...Its OK as long as you don't run em above 2000rpm,then make sure you run 50/1 mix thru it to flush before WOT use.

 

[mr geets]

I was told that Seafood was a good additive for ethanol fuel.

 

[ondarvr]

I was told that Seafood was a good additive for ethanol fuel.

Seafood and alcohol go very well together.

 

[ondarvr]

I have also seen firsthand what Seafoam in high consentrations can do to even a simple carbed motor. Not so much to the motor itself, but the fuel lines, gaskets and other rubber parts.

Seafoam contains a very high percent of alcohol, this combined with E-10 can really attack vulnerable components. I've seen fuel lines that had no problems with E-10 swell, soften and start leaking in just a few minutes after adding too much Seafoam, the same thing can happen with other plastic or rubber parts too.

 

[bruceb58]

No need to put snake oil in your engine.