Running rough

[cyclone]

I experienced a minor engine problem last night. I had an intermittent hard miss that started in the late evening. I think it may be water in the gas, I am going to replace the fuel filter now. I may put plugs in it if that doesn't fix it, they have 440 hrs on them. Lifetime is 1k hrs.

Anyone else have this problem before? I have heard that Epics foul plugs easily with bad gas. I'm trying the fuel filter first.

[Epicrider]

Pete,
I got hold of some bad gas last year and my boat wouldn't even get up to 3kRPM.I couldn't pull my wife up on her wakeboard.Changed the plugs...waaalaa.I only have close to 200 hrs. and they looked like crap.

[toyotafreak]

High compression, fuel injection and bad gas don't mix.

Have I said "powered by Chevron" lately??? :-)

[cyclone]

I suspected water in the fuel, I was using a lot of weight and the vent gets sprayed into a bit. I changed the fuel filter, it ran fine after about 1 min. No problems since, thinking about going out now.....

[Gearhead]

Juat as a hint - if you get some bad gas, or some low octane gas, make sure you turn the battery switch off for about 5 minutes once you get the fuel replaced with good stuff. That will reset the ECM back to its initial spark advance maps (it goes into a knock protect mode when you have bad gas or low octane gas and you will have reduced performance and fuel economy)

And yeah- Chevron is very good stuff. That, shell or BP are the only fuels I would even consider putting in my car or boat.

[davidgree1]

Do you turn off the battery after using the boat?

[cyclone]

I generally do to keep the batteries fresh.

Good point about the computer, it goes through it's learn cycle every time I kill power to it.  I had a little more rough running this weekend after buying gas on the lake. I almost never use "marina" gas. Had to a bit this weekend, but I topped it off with good stuff.

[ncarroll]

Hi all,

Well, haven't had the S22 for even a week and am experiencing the running rough phenomenon.  Going from stopped to cruising speed, the engine would kinda miss around 3000 RPMs, even if the throttle was all the way down.  Pulling back on the throttle and letting the boat plane out more slowly would get it up to speed.  First time it happened, the guage was only reading an eighth of a tank of gas, so we figured we needed to fill'er up.

We were going out to ski and in a hurry to catch the last light before the sun went down, so we put in a 5-gallon tank.  The first 20 minutes, we had no problems, but then again, the boat wasn't getting up to speed, having trouble pulling up a 120 girl.  Realized that the 5-gallon tank we put in was only 89-octane, as our tanks had gotten mixed up.

Next morning, put in 20 gallons of 91-octane (which seems to be about the highest we can find anywhere close...we have a bunch of 5-gallon tanks we fill up and transport in the car) and experienced no problems for the first hour of use or so, but then it started running rough and missing again.

The boat has an appt. scheduled tomorrow at the dealer for some stain removal on the ski-locker upholstery and they're going to look at the engine at the same time.  Is the common concensus that the plugs and fuel filter are probably the culprit?

-Nate

[ncarroll]

Update- not sure what this means, but tonight, we skied and wakeboarded for an hour with no rough running engine problems at all.  The only difference that I can find is that when pulling someone out of the water, instead of flooring it, I pushed down the throttle less than 90 degrees (more like 60-70 degrees).

[cyclone]

I have had intermittent problems, it is definitely a plug. Lower than 93 octane gas will cause runnability problems and fouling of the iridium tipped plugs. Swap both the fuel filter and the plugs and have a great summer!

[ncarroll]

Boat came back from the dealer running great last saturday and I've been having a great couples days this week on the water!!  Probably going to have to learn to replace the plugs and fuel filter sometime soon though if it ever happens again.

-Nate

[cyclone]

You should be good for quite a while, just keep the tank topped off and use good gas to avoid condensate problems. Plugs will be good for another 400-1000 hours.

[happ]

Just a note- I have found problems with rough running if my hull gets too much water in it. (leaky shaft seal,fat sack,bilge pump not on. ext.) Not shure why..

[toyotafreak]

When you guys replace spark plugs, do you spend the $100 for iridium-stupidium plugs or just get NGKs? If NGK's, do you gap them?

Finally decided that it would be prudent to add a fuel filter to the on-board spares. One of these days, I'll get a serpentine belt too (not sure where to store it though.)

[cyclone]

Use the Iridium plugs. You will have problems if you don't the engine/ignition system is picky about plugs. You only have to swap them out every five years or so, what's the big deal?