Any 2 stroke gurus here?

[Max Simmons]

Have a 1987 Evinrude 15hp that's been sitting for years collecting dust. Decided to sell it since have no use for it. last time I used it, I ran all the gas out of the carb and stuck it in my shop. Pulled it out, put in fresh mix (100/1) and tried to get it to start. Nothing. Pulled plugs and they appeared dry. Put a little gas in each cylinder, pulled and she fired off for a few seconds, but died. Appears electical is OK, no fuel getting there. Pulled off carb and got re-build kit. Re-installed and then it would start and run rough and only if I played with the choke. Any suggestions?
Our local Evinrude shop charges $110/hour and for a motor that is only worth around $600 I'd like to fix this on my own. Thanks

 

[Nomad Willy]

Just do the carb Max. Just a good cleaning w new gaskets. And perhaps the fuel pump.

Yup .. count me in for two strokes.

 

[Max Simmons]

I did rebuild the carb. Was going to do the fuel pump as well, but they sold me the wrong kit. Will replace and see of that helps.
Now, when I pull the choke out, it will start, start to sputter, then I push choke in, smoothes out for a few seconds, starts to sputter again, pull choke back out and it runs better for a few seconds, then sputters (repeat etc)

 

[Phil Fill]

First thing I do is replace the spark plugs every year. If its the fuel plump you should be able to continue pumping the bulb.

May/June is when I start up the 4 out boards, which I have not done yet as I have not replaced the spark plugs and new gas. I mix the oil 60 to 1. Are you sure 100 to 1 is correct? The 140 hp Merc is 1970, so I tend to mix the oil heavy.

 

[Max Simmons]

100/1 is what the manual calls for. There is some chatter on the web that they changed that to 50/1. The reality is probably more like 60-70/1

 

[jukesy]

When you rebuilt the carb did you replace the jets as well? Check to make sure the float is actually floating

 

[Max Simmons]

Yep. Replaced jets, float, needle valve. I was surprised that the carb was actually pretty clean.

 

[Nomad Willy]

I use 50-1
Even in my Evinrude e-tech.
There are times when doing other than what the owners manual says is best.

Prime it and then try to drain the float bowl. It nothing comes out look for a problem before the carb. "Primer bulbs" cause lots of problems. Orient your primer bulb so the arrow points up.

 

[Fishbucket]

Seems to me, there was no reason to re-build the carb.
And you had a fuel flow issue. which is still the case.

Try and get it started again with fiddling the choke, and like said... keep squeezing the bulb and see if you can keep it running. That would most likely indicate a fuel pump problem.
Being it runs smooth, for a time, says that the jet is not plugged and metering fuel just fine. Vacuum from the choke is pulling fuel thru the hose and into the bowl... where it runs out and not being replenished.
Take a good look at the hose and bulb too. a small air leak would cause the same issue.

my .02 cents

 

[OFB]

Check the kill switch and wires to it. For some reason your story is sounding familiar.

 

[jeffnick]

When you rebuilt the carb, did you 'boil' the body in carburetor cleaner and blow it out with compressed air? There's some mighty small orifices in there.

Otherwise could be just a mixture adjustment. Whatever you do, don't put gas in a spray bottle and use it to keep the engine running while you make adjustments (like I do).

 

[Max Simmons]

Well, rebuilt fuel pump. Re-assembled and absolutely same results. Motor will run but need to play with choke continuosly to keep running. Clearly a fuel issue. So, to date, fresh fuel, rebuilt carb, rebuilt fuel pump. Running out of ideas. This is now a challenge that I will not concede on.

 

[Pau Hana]

Is the tank to engine line good? We have a 35hp Johnson, and recently the tank side of the line had to be replaced.

 

[Bluto]

This is the same trouble motorcyclists have after storage. I have had excellent results by treating the last gas of the season with 'Sea Foam'.
It keeps carbs and injectors clean as a whistle for winter, can be used to remove carbon deposits, and stabilizes gas for months. It was originally sold for boaters, I think.
Works as advertised.

 

[chc]

Is there a filter anywhere in the line to the carb? Sounds like something is clogging the fuel path. Pick up point in the tank? We used to have a similar problem in our 2 cycle lawn equipment; generally turned out to be a clogged tank filter, or plugged line from the tank.

 

[Max Simmons]

It is a newer tank. I'll check the pick up. I did try sqeezing the bulb as it ran, but same results.
No fuel filter that I can find. There is just a screen at the fuel pump.

 

[Nomad Willy]

I think you may have done something wrong w the carb.

Another test is to rig an overhead fuel supply w hose to the carb. May need to get a small hose barb fitting to screw into the carb float bowel.
Then see if it will run. If it does your problem is in the supply like the tank, hose, primer bulb ect. If it behaves as it did before you've done something wrong w the carb. Take it apart and check the float and it's operation carefully. Make sure the float valve works by blowing and operating the float and needle shut-off valve to see if it shuts off and opens up properly. The float could be bent and sticking on the side of the float bowl.

Having done all that you should know what the problem is/was.

 

[Max Simmons]

Eric, you may be right.
Just downloaded 12 pages of carb info and we tear apart and re-do tonight.

 

[FF]

A good soak in laquer thinner should solve the problem.

Sounds like a plugged passage To the jets , so the carb cant transition from very rich idle to normal operation.

 

[Capt Kangeroo]

The comments here about the fuel line & bulb are on the money, most of the head banging problems I have had were the fuel line & connection at the engine. If it sucks any air at all, it will give your symptoms. I once had your exact problem that haunted me for days and it turned out to be the rubber fuel line had delaminated on the inside so as soon as the motor would start generating suction/pulling fuel, the fuel line would collapse internally and starve the motor. You could not see this on the outside of the hose and it looked clear when looking down through it. Was quite by accident I found the problem, you would think it rare but i have had it happen twice. Most of the time it is the crappy fuel line connector at the motor letting in air.

 

[3288MY]

Max, I'm coming late to the game, did you figure out what was wrong? I have an '86 9.9 Johnson, which should be very similar to yours and I had the same issue that I could make it run by playing with the choke. I cleaned the carb (used aerosol carb cleaner) and also bought the carb rebuilt kit. That fixed the problem for me. My carb looked very clean even before I cleaned it, but I suppose with these small passages it doesn't take much. I read somewhere else that a good carb cleaner is to let the whole carb soak overnight in Pinesol. I haven't tried that myself.

 

[bligh]

after u chek your fuel lines tank, filter, etc, make sure your low idle jets are clean, even if you just replaced them, make sure you inspect them again.

 

[RickB]

You didn't say and no one asked ... when you squeezed the fuel bulb, did it get hard?

Disconnect the fuel line at the engine and use a thin screwdriver or something similar to depress the ball on the check valve on the fuel line connector while squeezing the bulb. Do you get a good flow? If so then the issue is on the engine and not your fuel line or tank.

Open the drain on the carb bowl after pumping the bulb. Do you get fuel? Does fuel flow from the drain as you pump the bulb?

Does fuel flow from the drain as you pull the start cord? If not then check the on engine fuel pump.

But, since you say it runs off the fuel you put in the cylinder directly, and if all the tests above show fuel being delivered to the carb then your problem is in a clogged passage in the carb body. Take it off and start again, this time use a very thin soft wire to probe all passages and use compressed air to blow out all the ports and passages. Check all the diaphragms and needles.

With the air cleaner off, cover the air inlet to the carb with your hand while pulling the start cord, do you get a good suction? when you crank rapidly is there air blowing back out?

 

[Max Simmons]

Since my last post, I have re-adjusted the float, and in the process broke the float bowl (pay attention to the tightening sequence). Replace the bowl and now It will turn over without priming the cylinders, still won't run. I suspect that there is air getting in the line. The fuel line from the fuel pump to the carb utilizes a plastic elbow and when I pump the the priming bulb, I hear air coming from there.
There are plastic clamps, similar to zip ties, and one is cracked. Plan on replacing these. Any reason why a small hose clamp would not work?

 

[Max Simmons]

And the winner is.................FF!
Took the carb apart again, soaked it in laquer thinner for 3 days (actually forgot about it) re-assembed and fire off on second pull, idles well and no monkeying with the choke.
This really surprised me because I felt that you could see all the passages and they all looked clean. Anyway, it's now on Craigslist and ready for it's next adventure.

 

[Nomad Willy]

Re FFs recommendation ..

Why use lacquer thinner when there is a product especially made for that purpose ... carburetor cleaner. Nasty stuff.