Too much Seafoam?

woodnknots

Petty Officer 3rd Class
Joined
Oct 20, 2006
Messages
96
Can too much seafoam in the gas/oil mix cause a power loss?

I was out on the water all last weekend pulling a tube with my 1990 Force 90. Saturday and Sunday I had no problems whipping the kids around (slinging them out of the wake, etc...), but Monday afternoon towards the end of the day I was noticing that I just couldn't get even one person out of the wake like I was doing earlier in the day. The tide had shifted a bit at that point, but I couldn't see that causing it.

The motor never sounded ANY different all day, and ran very well all the way to the dock, but I seemed to lose a few MPH from before I was pulling the tube to after I was pulling the tube. There was quite a bit of water in the hull, and likely a bit of a weight difference, but other than that I couldn't come up with any ideas. Once I noticed that I was having trouble with speed (minor though it was), I decided to get back to the dock before my luck ran out. Like I said, it ran well all the way, and even idled like a champ for probably 15-20 minutes while I waited my turn at the dock without dying.

The reason I ask about too much Seafoam, is I ran two cans in a full tank (about 20 gallons), then filled up after the first day (about 5 gallons) put in another can, then filled up after the second day (about 9 gallons) and put in one more can. (I was trying to decarb while using the motor). The third afternoon is when I noticed the "problem", and it was after using the motor pretty hard for an hour or so, then resting it for 2 hours while swimming, etc, then running it hard for another hour or so before I noticed the speed issue.

There is a good chance that this could all be in my head, but I wanted to cover my bases. Sorry for the long post!
 

SuzukiChopper

Senior Chief Petty Officer
Joined
Oct 10, 2004
Messages
782
Re: Too much Seafoam?

I would venture to guess that the fact you were trying to decarb while running would have possibly caused it. The instructions on the can (if I recall correctly) say to change the plugs after you're done. Decarbing is one of those things that I don't think you should be doing while running your motor hard (again, the instructions suggest to do it at idle after the motor is warm) and just think of the crap you'd be dumping into the lake (not like there aren't worse things).

Seafoam in your oil or in your tank is supposed to be a preventative thing to help keep things clean, not to actually do the decarbing (which is done through the carbs themselves). I would suggest not putting anymore in and run that tank close to empty and follow the proper procedure for decarbing.
 

freddyray21

Commander
Joined
Jun 10, 2006
Messages
2,460
Re: Too much Seafoam?

you could have also loosened a lot of crude in the tanks. I would check whatever filter or screen you have going to the carb. Clean or replace it.
 

Gary H NC

Fleet Admiral
Joined
Dec 1, 2005
Messages
8,972
Re: Too much Seafoam?

I doubt you put enough in to cause a problem.I would change the plugs for peace of mind and keep running it.Maybe a fuel filter change also.I have run 4 cans in about 24 gallons of fuel,if anything the engine idled better.
Remember also that weather conditions like heat and humidity can effect top end speed also..
 

woodnknots

Petty Officer 3rd Class
Joined
Oct 20, 2006
Messages
96
Re: Too much Seafoam?

I doubt you put enough in to cause a problem.I would change the plugs for peace of mind and keep running it.Maybe a fuel filter change also.I have run 4 cans in about 24 gallons of fuel,if anything the engine idled better.
Remember also that weather conditions like heat and humidity can effect top end speed also..

I'm sure you're right, it's probably all in my head. Like I said, the motor NEVER showed any signs of problems before I noticed what I perceived to be a speed loss. Besides, I've only got to have this boat last a couple more months, then I deploy, and I'll probably sell and get another boat when I get back next year.
 

hkeiner

Lieutenant Junior Grade
Joined
Oct 17, 2006
Messages
1,055
Re: Too much Seafoam?

I use a 3 gallon portable tank for decarbing with Seafoam. I mix 1 can Seafoam per gallon of fuel in the portable tank. Using a portable tank lets me better control the Seafoam concentration level and I can also easily switch between the the Seafoam mix and regular gas.
 

hkeiner

Lieutenant Junior Grade
Joined
Oct 17, 2006
Messages
1,055
Re: Too much Seafoam?

I use a 3 gallon portable tank for decarbing with Seafoam. I mix 1 can Seafoam per gallon of fuel in the portable tank. Using a portable tank lets me better control the Seafoam concentration level and I can also easily switch between the the Seafoam mix and regular gas.

The FAQ has an article on using Seafoam that may be helpful.

http://forums.iboats.com/showthread.php?t=158076
 
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