Not long ago I purchased a used 2000 175 Scout boat equipped with a low hour 1996 90 hp Honda 4 stroke . What happens is when taking off it is sluggish and sometimes stalls when using full throttle and also it seems I detect a skip until it gets up speed. It has a 13 1/2 X 17 prop which from what I read is about right for this boat but the RPM’s only get to around 4700 . It runs great otherwise.
My question is should I use Seafoam or some other product . The motor has about 250 hours and has not been run much the past year and 1/2 , maybe 6 times .
Thanks Sid
It may help but it’s not worth the risk of blowing an engine from fuel starvation or whatever is causing the problem. Have you changed all your fuel filters?
If so and you know your gas is good, I’d have it checked out before you run it too much.
A cars fuel system is sealed from the atmosphere basically whereas a marine fuel system is not. More opportunity for moisture intrusion. And correct about length of time fuel is in the tank.
Russ B. Formerly known here as “Top2Bottom1” www.joinrfa.org
God is great, Beer is good, People are crazy
I had the same problem in my yammy. Save you some time and get the injectors tested and cleaned. My guess is your running on 1 or 2 injectors and the others fail. You can either pull them out yourself and send them off to injector man (http://fuelinjectorman.com/) or go to someone who is certified for honda.
“My fish served a whole lunchon. Your fish look like a munchkin”
bitefish got it above, but here’s dunk’s method written by him - cantankerous old coot but he knows his stuff when it comes to using seafoam…He writes:
dunk’s decarbon method
This works for Carbed, EFI, Ficht, HPDI, Optimax and even 4 strokes…
First you need a separate small fuel tank. One of those 3 gal red Tempos works great or an empty gal milk jug will also work, but might be a bit messier…
I use Seafoam over the OEM stuff like OMC Engine Tuner or Merc Power Tune because in the last few years they changed the formula and you have to let them sit up 12 hours. Who’s got time for that?? Seafoam you can buy from NAPA, CarQuest or other auto stores. Seafoam works in 15 mins.
You’ll need 3/4 gal of gasoline and one 16oz can of seafoam for each engine. Don’t forget to add 3oz of oil if you are premixing in a carbed engine. Use about 3 ft piece of fuel hose off the little tank. You connect this tank to your engine by pulling off the main tank fuel hose off the intake side of your water separating fuel filter and plug the hose off the small tank on to that fitting. Or you can separate the fuel line on the tank side primer ball, so you can still use your primer. If you have an engine that has fuel plug then you need a fuel plug on the little tanks hose.
Start the engine, let it warm up and start pulling the mix into the engine. You may have to increase the idle to keep it running once she get loaded with the Seafoam. Run the engine 15 mins in the dock or just cruising around under 2500. Then shut it down and let it sit for 15 mins. Restart the engine, the smoke you see is the carbon burning off. Do the whole thing again and let her sit again for 15 mins. If she smokes after the second time do it again, but I’ve never seen one still smoke after three doses. The gallon mix should be enough to do this 3 times. You don’t need any wide open throttle, you don’t need to change the plugs. If it’s cleaning the combustion chambers it’s also cleaning the
I agree 100% with carbon build up in 2 strokes because of the oil mixture…but 4 strokes carbon build happens with cool running engines, extended idle has more carbon issues etc etc… high reving engines run hotter meaning carbon has less chance to form
I use additive for the ethanol fuel because boats don’t have EVAP systems meaning they are vented and a tank of gas may sit for a month before it is used totally.
