115 HP Johnson Outboard 1983?

[jigginlow]

After fogging my 2-stroke engine for the 1st time last fall, I am having engine-related problems. When I took it out for the first time this spring, it started up just like it always does, but seemed to be lacking rpm on high idle and also struggled to stay running on low idle. More importantly, when I move the handle forward to engage the prop, the engine dies, and dies, and dies... Well, I did the ususal things like replacing the plugs (thinking they were fouled from the fogging) and putting some non-ethanol gas and sea foam in the carry-on fuel tanks. All of these efforts have been in vain so far. I have 2 carry-ons and I have tried running it out of both to rule out tank venting/plugging issues with no success. One thing I observed is that the primer bulb does not seem to stay hard like it once did. I'm wondering if anyone has had problems with the primer bulb/hose providing fuel to the engine? Thanks in advance. By the way, I did check the fuel filter and there are no plugs and I did observe that the plugs don't seem to be in their usual really dry state. Thanks again.

[para1911]

You said you have portable tanks and the primer bulb gets soft...Check the Orings (seals) on the ends of the fuel line. If there is a leak in in one of these it will be sucking air in with the fuel...or just air sometimes. Try a different fuel line if you have one.

[para1911]

If the plugs are wet looking you may still have fogging oil in the engine. It sometimes takes quite a while to work the fogging oil out and a couple sets of spark plugs may get fouled in the proscess. After running the motor for a half hour (completly warmed up) the plugs should look a little darker than cardboard color. If not, you've got fogging oil left in the system, bad fuel/air mix or too much injection oil.

Good luck!

[jigginlow]

One more comment in regards to the fogging process after you commented on the oil still remaining in the engine- it literally took several minutes for the engine to finally stall out after spraying the fogging oil into the air intakes alternatively. Is this normal, do you think?

[marine_man]

If you were trying to alternate with one can, then yes, that's not that uncommon. Next year get two cans and you'll be set.

You didn't by chance reverse the fuel hose, did you?

Also, does the primer bulb get soft when you're running the motor on the normal fuel tank?

Did you put stabilizer in the gas and run it through the motor prior to putting it away for the winter?

marine_man

[jigginlow]

I was alternating with only one can of fogging oil- I will do as you suggest next time. The primer bulb gets soft regardless of which carry on fuel tank I use- I do not have a built-in tank. And yes, I did put stabil in the ethanol- blend gas that I think I would have had in there at the end of the season. As I understand, there is a special blend of Stabil for ethanol gas- do you know that to be true. someone told me that ethanol and regular Stabil do not like each other when mixed. Thanks again.

[marine_man]

I've never had an issue using the regular stabil with ethanol gas.

It sounds like your fuel pump could be weak (based on the primer bulb comment), but having wet plugs (indicating extra gas) and a weak fuel pump don't make sense together.

You put the stabil in and ran the motor, correct? Just making sure I fully understand your comments.

marine_man

[jigginlow]

I went home at noon and checked to see that the primer hose/bulb was not reversed-it wasn't. With the hose disconnected from the quick fitting at the engine, pumping the bulb made it rock hard and seemed to stay hard in the little bit of time I looked at it. I have to admit I don't think I ran the stabil through the components on the engine-I should have but I think I had already put my garden hose away for the year and neglected to do it. Maybe I have a sticky float on one of the carbs- would this lead to the criteria I've described. I'm pretty weak on carburetion-maybe I need to do some dismantling for further inspection. Thanks.

[jigginlow]

Also, when I took the cap off the gas tank there was a substantial amount of pressure in there- it blew gas all over my hand when I did so. Shouldn't that pressure be relieved is some manner while sitting.

[marine_man]

If you have a portable tank, and the vent is closed, then no, there's no relief.

On the primer bulb - will it firm up (and stay firm) when it's connected to the engine?

If you didn't get the stabilizer run through the motor it is quite possible that you have a gummed up carb, which would explain the symptoms you're seeing. However, it would be good to know the answer to my primer bulb question first. It's possible you have a pinhole in your hose, which isn't helping the situation, but not the main contributor in my opinion.

marine_man

[Jim Uran]

Marineman, got a question while you folks are talking about carbs. What does it run to have one rebuilt, generally?!??!?

[boatfixer]

Leech, about 1 hr per carb plus a kit.

While running, primer bulbs shouldnt remain hard anyway. Once you have primed the float bowls and the needles are seated, the primer bulb has done its job and now should "free flow" gas through it while running. You can, however, feel for the bulb to be full of gas while running, but I wouldnt be alarmed if it is not very firm.

That being said, bad fuel pumps can in fact cause an excessively rich condition. The diaphram gets its pulses from the crankcase and in the event of a ruptured diaphram, it can inject gas directly into the crankcase causeing a rich condition. Especially if you try pumping the bulb while the engine is running.