Merc I/O 190 running rough after seafoam?

[LionsFootball]

Hello, I've been hearing from so many people to run seafoam through our boat engine at least once a year. I did run some through the engine the other day and by the end of the day the boat would bog down when trying to go fast. It slowly got worse and we had to run t back to the boat launch at an idle or it would stall out. I've been reading on here and it sounds like it may be the plugs? I just wanted to reach out and see what the problem may be and if there is anything I should check for? Also, should I not be using seafoam? Now I wish I never used it! haha Thanks in advance!

 

[ondarvr]

Probably not the plugs, more likely some gunk was loosened by the Seafoam and is now plugging up the carb. Seafaom can dissolve some rubber fuel line and O-rings, so don't use high concentrations

 

[salty3rd]

Sounds like Carb; if not, I would suspect the coil before the plugs

 

[Scott Danforth]

Sounds like Carb; if not, I would suspect the coil before the plugs

coils almost never go bad on an I/O (maybe 2 out of 10,000 changed coils are actually bad), people change them and throw money away because they dont know better

 

[HT32BSX115]

should I not be using seafoam? Now I wish I never used it! haha Thanks in advance!

Well, I think you have answered your own question! There is no "mechanic-in-a-can"

Mixtures of naphtha, mineral oil, kerosene and other solvents usually do not "fix" anything. They're a really good deal for the companies that sell them though!!

You likely need to 'fix' your fuel system or rebuild the carb

 

[salty3rd]

coils almost never go bad on an I/O (maybe 2 out of 10,000 changed coils are actually bad), people change them and throw money away because they dont know better

Well I guess I had bad luck then. Because I Chanded coils a few times over the years when I was running the 470's and it fixed the issue. One of the issues was similar to what was described in this thread. And yes they were the correct coils with the resistance wire removed. I have seen coils go bad in friends boats also. I think 2 in 10000 is a little extreme.

 

[LionsFootball]

Thanks for the feedback so far! I tried it again today and after bogging down at full throttle again today it ran fine for quite a bit. Then we beached and hung out for awhile and we took off and everything was fine... until we got back to the boat launch and it started making a ticking noise. I took a quick video before pulling and it's below. Any ideas? Thank you!

 

[Bondo]

Ayuh,.... Welcome Aboard,..... Time for a compression test,... sounds like serious problems,....

Here's My guess as to what happened,....
Ya dumped the sea foam into the tank, 'n it dislodged abuncha crud, which washed down to the fuel filter,....
Some more of the crud probably also washed into the carb,....
That's why it had no power, 'n ran like crap,....
it was starvin' for fuel,...

Because ya kept runnin' it, Lean,....
It's since detonated itself into a Major repair,....

But that's just My guess,.....

 

[Scott Danforth]

Ayuh,.... Welcome Aboard,..... Time for a compression test,... sounds like serious problems,....

Here's My guess as to what happened,....
Ya dumped the sea foam into the tank, 'n it dislodged abuncha crud, which washed down to the fuel filter,....
Some more of the crud probably also washed into the carb,....
That's why it had no power, 'n ran like crap,....
it was starvin' for fuel,...

Because ya kept runnin' it, Lean,....
It's since detonated itself into a Major repair,....

But that's just My guess,.....

What he said

 

[Silvertip]

Your boat has gauges. What does the Oil Pressure gauge read now and before the noise started. It also has a Temperature Gauge and I ask the same question. What did it read before and after the enema. And finally, someone suggested looking at the plugs. But you apparently have not done that which would have taken about 10 minutes. Carbon can come loose and dance around inside the cylinder. So do some investigating.

 

[ondarvr]

Yes, at this point plugs may tell you something, melted or smashed is bad.

 

[LionsFootball]

Your boat has gauges. What does the Oil Pressure gauge read now and before the noise started. It also has a Temperature Gauge and I ask the same question. What did it read before and after the enema. And finally, someone suggested looking at the plugs. But you apparently have not done that which would have taken about 10 minutes. Carbon can come loose and dance around inside the cylinder. So do some investigating.

Thanks for all the input! A couple of the post really got me worried it might not be as simple of a fix as I am hopinh and above my capabilities. So I dropped it off to our mechanic, who is also related to my dad, so I trust him. I was hoping for an easy fix but I'm worried it's not. :/ I hate to drop it off like this in July but we do have my dad's Malibu to use too so the trade off isn't too bad for a couple weeks!

Again, thanks for the feedback! This seems to be the best boat forum around! I will update the post as soon as I get word back!