View Full Version : using seafoam to fix a 2 stroke gummed up from ethanol.
LacLaBicheNS
08-27-2012, 08:15 PM
My buddy has a 50 horse merc from the late 70's.
It always ran great, no issues. Until the last time we used the boat before winter storage last fall. My buddy usually puts premium from shell in the tank to avoid enthanol. That day he filled the tank with reg from a no name gas station.
When we started the motor up in the spring it would stall past half throttle. We tried everything, fuel lines, fuel filter, fuel pump, plugs, new gas etc..
I am pretty sure the floats in the carb are stuck. Due to crappy reg gas the motor was stored with. My budy forgot to add any fuel stablizer also.
We haven't used the boat all summer, we use mine instead.
I've never used seafoam but picked some up at the local auto parts store. The can states varies ways to use it. In order to get lots of seafoam right into the floats in a concentration high enough to maybe free them the method seems to be: put the fuel line directly in the can of sea foam with the motor running. When the seafoam is in the engine turn it off for 5-10 mins. Then fire the engine up to burn off anything the seafoam got rid off and hopefully the motor will function.
This sounds fine, but should I add some 2 stroke oil to the can of seafoam if I am putting the fuel line in the can? If I don't the motor will be running with no oil in it. I know it wil be just idling for a few mins, but will it be fine to do this proceedure?
bagwan
08-27-2012, 08:25 PM
I don't know how many cylinders in that engine but I had a 6 cyl 115 that was only running on half the cylinders. Limped home at just above idle and if you revved it up it would conk out. One power pack that fed three of the plugs was toast. Very similar symtoms. Dealer said to change them in sets but I inststalled just one and she worked good.
sparky660
08-27-2012, 08:26 PM
I don`t think the floats are stuck. If they were stuck you would either get no fuel or way to much.
Ken07AOVette
08-27-2012, 08:29 PM
Paging OJ.....
2 strokes need oil but it takes a while to cook them, less that wot for short bursts you may be ok
Sea foam pored into a 4 stroke kills an engine.
But I like it
[QUOTE=Ken07AOVette;1578931]
Sea foam pored into a 4 stroke kills an engine.
I thought it was safe for all engines?
skidderman
08-27-2012, 09:25 PM
If it's the carb, best to pull it, take it apart and soak it in industrial carb cleaner. If you take it apart you should be able to tell. Gas today is terrible stuff.
LacLaBicheNS
08-27-2012, 09:27 PM
I don`t think the floats are stuck. If they were stuck you would either get no fuel or way to much.
This is whats happening thought. The cylinders get flooded past half throttle.
When we kept it under half throttle the motor behaved fine. When we took the pluggs out, they were bone dry.
When we went past half throttle, the motor died almost instantly. When we took the pluggs out after this, most were soaking wet. Like dripping wet.
TO me this means its not a power pack, because at less than half throttle the plugs all fired fine.
Ken- I think it would be ok to run pure seafoam for a min. I might put a bit of 2 stroke oil in the seafoam can though. If I mix the oil and sea foam 75:1 I think it would still clean the crap out. The motor is supposed to run 50:1, but at idle it doesn't need 50:1.
Ken- sea foam mixed 1 ounce or 0.5 ounces to every gallon will not wreck any motor. I read all about people saying it add's to much alochol. But at 1oz seafoam to 1 gallon gas its only raising the alchol to 0.1% according to the numbers.
Enthanol is the absolute worst crap ever invented in the gas industry..
-Personally it almost wrecked my 76 evinrude 15horse because I ran reg gas in all this summer. It clogged the motor up so much that when I went to take the pluggs out it was like the plug threads were covered in molasses. I ran 60 litres of gas with a fuel treatment through the motor in about a week and it cleaned it out thankfully.
- had a buddy whose street bike needed a new gas tank and new carbs because of ethanol. Total bill was about 3 grande.
-now my other buddies merc is messed up from it.
LacLaBicheNS
08-27-2012, 09:28 PM
If it's the carb, best to pull it, take it apart and soak it in industrial carb cleaner. If you take it apart you should be able to tell. Gas today is terrible stuff.
ya thats going to be a winter time job. We are looking for a quick fix to get it running for the fall. In the winter its going to be semi rebuilt.
LacLaBicheNS
08-27-2012, 09:29 PM
I don't know how many cylinders in that engine but I had a 6 cyl 115 that was only running on half the cylinders. Limped home at just above idle and if you revved it up it would conk out. One power pack that fed three of the plugs was toast. Very similar symtoms. Dealer said to change them in sets but I inststalled just one and she worked good.
motor is a 4 cylinder late 70's merc. I don't think its anything to do with spark. See my above post.
JohninAB
08-27-2012, 09:53 PM
Sounds to me you may have an air fuel mixture problem. Not getting enough air at high speeds therefore basically choking the motor out with raw fuel or you have a weak spark at higher RPMs.
If the float was stuck you would either be pouring way too much fuel in all the time or getting no fuel at all.
Have you checked the timing?
Ethanol is not great in 2 strokes as oil does not mix in with it. Why manufacturers state less than 25% ethanol content in fuel. I run 10% ethanol gas in my boat with absolutely no problems. Same with my vehicles as most all other motorists do.
My comments for what they are worth.
LacLaBicheNS
08-27-2012, 10:01 PM
Sounds to me you may have an air fuel mixture problem. Not getting enough air at high speeds therefore basically choking the motor out with raw fuel or you have a weak spark at higher RPMs.
If the float was stuck you would either be pouring way too much fuel in all the time or getting no fuel at all.
Have you checked the timing?
Ethanol is not great in 2 strokes as oil does not mix in with it. Why manufacturers state less than 25% ethanol content in fuel. I run 10% ethanol gas in my boat with absolutely no problems. Same with my vehicles as most all other motorists do.
My comments for what they are worth.
Interesting..
We haven't checked the timing. This was going to get done along with the points in the winter.
Its the circumstances that the motor acted this way which is why I think its ethanol.
-ran great last time we used it before winter, but he put crap gas in it.
-the very first time we took it out this spring and tried to accelerate away from the dock, it died. Never worked right from the day it came out of storage.
If it was timing, I don't think it would happen like this. I'm not sure what would cause the air/fuel mixture from changing over the winter all of a sudden either.
I'm no boat mechanix either so my opinion is just my opinion. I did talk to a marine tech and he said most likely stuck floats and gummed up carb. So I'd like to attack that first before I try spark, timming, air mixture.
WCTHEMI
08-27-2012, 10:07 PM
I would think it would be less hassle to take the carbs apart to clean them, then you will be able to see what, if anything is gumming them up.
JohninAB
08-27-2012, 10:14 PM
Any gas left in a carb for extended periods will varnish up the carb and cause grief. Ethanol makes no difference in this. Happens with non ethanol fuel or fuel with ethanol in it. If the motor is a late 70's Merc it should be a Thunderbolt ignition system I would think which means no points but electronic ignition.
jim summit
08-27-2012, 10:26 PM
Pull the needle and seat, sounds like junk is restricting fuel flow into the carbs. It will run up to a certain rpm then start starving for fuel. Had to do this for numerous customer outboards.
Ken07AOVette
08-27-2012, 10:27 PM
Ohhhhhhh....
I spelled poured wrong:sign0176:
Damn auto correct!
beltburner
08-27-2012, 10:31 PM
grab a can of mercury power tune and run it through the carbs,, it worked great on my 84 twin mariner. if it doesnt work then you might have some real carb issues especialy if they wern't run dry before the winter.
LacLaBicheNS
08-27-2012, 10:56 PM
Any gas left in a carb for extended periods will varnish up the carb and cause grief. Ethanol makes no difference in this. Happens with non ethanol fuel or fuel with ethanol in it. If the motor is a late 70's Merc it should be a Thunderbolt ignition system I would think which means no points but electronic ignition.
I just did some reading, ya its a thunder bolt and has no points. I don't know how the ignition system works. I'll have to do some more reading before we pull it apart this winter.
I know gas left in the carbs can varnish without ethanol, but its more likely to happen and more likely to cause more damage with it than with out it.
LacLaBicheNS
08-27-2012, 10:58 PM
Pull the needle and seat, sounds like junk is restricting fuel flow into the carbs. It will run up to a certain rpm then start starving for fuel. Had to do this for numerous customer outboards.
This makes sense. I will try this as well.
It is easy for me to pull the carbs and points etc.. But its not easy for my buddy who is mechanically challenged. So anything we can try thats easy and without dissassembly is good right now until I can clean some space in my garage when I get time and take it apart.
Kim473
08-28-2012, 06:58 AM
Pull the needle and seat, sounds like junk is restricting fuel flow into the carbs. It will run up to a certain rpm then start starving for fuel. Had to do this for numerous customer outboards.
The seafoam may clean these out it's self. If pulling the needle, count how many turns to take it out so that when you put it back in you have the right setting or close to it.
Rather than putting the fuel line in the bottle of seafoam, would'nt it be easier to add the can of sea foam to just a gallon of gas or so. Drain the tank if you can and only leave a gallon of gas in it or so. If you have a metal gas tank, they can start to rust on the inside. This rust will travel up the fuel line and plug the filters, and needles in the carbs. Check your gas can and see if there is rust in it. If so, I think you will be taking the carbs apart.
The first thing I would do is drain the gas into a container and check for rust and dirt. This could be the cause of all your problems and sea foam will not help. It may help for the short term but mabe only 15 mins and problem will come back. After that then pull the needles and clean away. Watch that you don't damage the needles and seats, they are very smooth and delicate for a reason. Treat them like a fine woman. Very,Very well you know.
silver
08-28-2012, 07:07 AM
If that were my unit, I would get some carb cleaner/fuel in jector cleaner and run that fairly concentrated. It comes in a small bottle, maybe 8 ounces or so, pour it into a gallon of fuel mixture and run that. If it is a bit of crud it may take it out fairly quickly. If it does, top up your tank with fuel mixture to dilute the cleaner.
Let us know what works.
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