sea foam

I have a 1972 9.5 sport twin with a rough idle and a little hard to start. I rebuilt the carb and it helped a lot. I have seen on this site people talking about seafoam .What is it and is anygood?

Re: sea foam

seafoam is a "de-carbon" fluid.... Basically it's made to remove carbon deposits off the inside of the engine... Being 2-stroke and burning oil means carbon builds up on the pistons and exhaust...

It's available in two forms... One is a "liquid" you mix in with your gas and the other is a "spray" you spray directly into the carb...

I believe most folks just mix some in their gas every once in a while... I like the idea of the spray myself...

You can also find it under some other names... Seafoam just happens to be the more popular one... I believe the OMC version is "Engine Tuner"...

One word of note... Especially if you use the spray... Prepare the neighbors and perhaps the fire house in advance... When that carbon burns off the motor is gonna fog out smoke like you've never seen before... And I don't mean that light whispy bluish two-stroke smoke you're used to... This thing will FOG out some SERIOUS heavy standing white thick smoke... Thing 50 fog machines all attached to your transom running wide open... LOL

Re: sea foam

And to answer your question a little more directly... If their is carbon build-up (And there certainly is unless it's been removed before) then yes, removing the carbon will help... ASSUMING the pistons and rings are good... Before doing anything you might want to consider popping the bypass or exhaust cover off and checking the piston rings... (make sure they still have good "spring" left in them... Otherwise it's entirely possible de-carb'ing the pistons could actually lose compression and make things worse!

Of course I guess at that point it's a matter of opinion what worse is...

Re: sea foam

For me it alway's worked good and especially on 2 stroke's that may gum from sitting. About $6.00 a pint can. Just follow directions.

Re: sea foam

TD has a write up on it but i couldn't find it.

Here is another write up on the decarb method,
http://forums.iboats.com/showthread.php?t=158076

Re: sea foam

thanks guys Ill give it a try and hope for the best.and by the way are pistons and rings still available for this motor it has lots of hours on it dont know the compression but will check if parts are out there.

Re: sea foam

Gary H NC said:

TD has a write up on it but i couldn't find it.

Here is another write up on the decarb method,
http://forums.iboats.com/showthread.php?t=158076

Click to expand...

Here's a TD sticky from the Johnson & Evinrude forum on decarbing, carb cleaning and other topics:
http://forums.iboats.com/showthread.php?t=299680

Re: sea foam

I would strongly advise you to check your compression before and after the decarb. Then you'll know if it helped or not. I think you will be happy with the result. I did my 4 HP last year and was dissapointed at the lack of smoke. A little later I re-checked the compression and to my surprise it was up almost 15 lbs.on each cylinder. Even though my engine didn't have a lot of carbon the rings were obviously stuck to the pistons. Best of luck. Rick.

Re: sea foam

Sea-way marine still has pistons and rings available. They're spendy though.