Engine Sputter is back

[whammond]

FYI mine doesn't come off with an oil filter wrench. Mine is that bolt in the top you can see in the picture. Take that bolt out and it slides out underneath.

[trayson]

FYI mine doesn't come off with an oil filter wrench. Mine is that bolt in the top you can see in the picture. Take that bolt out and it slides out underneath.

mine too.........

[trayson]

When you said it happened last after a long ride (5 - 10 min) at relatively high speed, I was thinking it sounds like a fuel line collapsing internally. Pretty hard to diagnose, other than running it that same way on an external fuel tank to see if the problem goes away. But replacing the main fuel line isn't that bad of a job, maybe it's worth doing, unless you have done it very recently. Just a thought. Ethanol blended fuel is really tough on old fuel lines. But your symptoms make sense, in that it only happens when you're drawing a large volume of fuel for a long continuous time. But that scenario also can stir up crap in your fuel filter, or any residual water too.

How long of a run of hose would I need to replace the fuel line? I'd prefer not to remove my old hose until get the new hose so I can use the old hose to fish it through...

[ssa]

I believe skidim sells it in 5 foot increments. I replaced mine over the winter and 15 feet did it. I believe I had about 2 feet left.

[whammond]

Its not bad to fish it through. Just went around the fuel tank and fed up the bilge. One thing you might wanna check is the right-angle hose barb at the top of the fuel tank, mine was corroded and needed to be replaced. PO must've let is sit with untreated ethanol gas.

[Supra-in-steamboat]

Agree on the external gas can, start there. I do empty the fuel filter canister a few times a season. If the triple bump comes back with the external tank you know to look at your carb or...does your boat have "limp" mode? Some Pro Boss set ups came with, pardon the terminology, coil packs and sensors. I helped a friend with a 92 last year same issue. Still had issue after external tank was used so we used a jumper wire to individually bypass the sensors to rule them out (4) I believe. Still had issue so pulled carb bowls, emptied and replaced. Still had issue, replaced carb power valve. No more issue. Hope this helps. Good luck.

[trayson]

So I added a bottle of heet into the tank, then drained it and put the fuel into my wife's truck. (which has consumed the fuel with no issues).

I filled the tank with new fuel, but put in 2 bottles of HEET for good measure to go with the new E10 gas. Since I wanted to keep some things consistent for comparability and troubleshooting, I gave it 87 octane again like I have all year. My old roomie was a lifetime ford mechanic and build ford drag racing engines. He confirmed that what PCM said was accurate, that our engines are designed to run on 87 and unless we're running high compression or doing something to advance the timing, that 87 is all it needs.

I changed the fuel filter (water separator) and also checked the filter (screen) that's on the carbauerator itself and it looked great. I sprayed that screen with carb cleaner for good measure. Likewise, I sprayed a bunch of carb cleaner in the engine while it was running on the garden hose with the new gas in it.

It seems like this stuff worked??? I didn't have any problems last night and burned about 9 gallons of gas. I was going at speed most the time.

I guess we'll see what happens from here on out...

[SquamInboards]

One last thing (and I hope this isn't it). My boat underwent some really weird sputtering, then had issues starting while hot, and then starting at all. It was the protec ignition going bad, and basically the coil packs leaked out and it died so I had to do the whole electronic distributor conversion kit.

I don't know how I missed this since you have a 1992... do you have the ProTec ignition? If so, this is a common failure point and can cause weird run issues. Although your issue does seem to point to fuel, the fact remains that most people with the ProTec ignition system can be trouble.

That being said, if you can replicate the problem and find that it runs well on an external tank, that will be a nail in the coffin of "it's something on the engine" and then I'd be thinking about the ignition system.

But let's all hope that you've solved it!

[CJD]

Don't feel bad about all the work. Twice in my life I have spent $thousands on a cars I've had that sputtered and threw codes...only to find that a tank of bad gas caused the whole episode. Water in the gas is one of the hardest things to diagnose, and even harder to get out of your system. It collects everywhere. I think you did good by covering all the nooks it was hiding in at one time!

[trayson]

So the boat ran great, consuming 9 gallons of gas on Wed evening with NO issues. Topped off the gas tank afterwards.

Then today we drove 15 minutes to our spot. filled up the bags and started to get in our first surf. Made it partway through the first ride and the problems resurfaced. I figured out that the "bumping" sound was actually the exhaust. If I gave it more throttle after the exhaust started making the bump sound, it'd cough and sputter. So we stopped. We anchored and let the kids play on the beach. I took off my fuel filter and drained the gas that was in the bowl into a water bottle. Put the boat back together and had lunch. Then we drained the bags and the engine seemed to run fine. Took about 1/2 of a wakeboard run and then the engine started with the same problems. Came back in the boat and it wouldn't let me go more than 12 mph without problems.

So, on a whim, I dumped a bottle of HEET that I had in the boat into the gas tank. The boat was literally off for as long as it took me to unscrew the gas cap and dump the bottle in. I started the boat up and it drove FINE the rest of the way back to the launch (15 minutes at 20 to 30mph). And even performed fine for a 6 minute run pulling my friend and his son on the tube. We had to get off the water after that. Only went through 5 gallons of gas today.

It honestly doesn't make sense to me that the Heet could have worked virtually instantly. So I'm wondering if the gas tank isn't venting properly (because I extended the vent line to the front to protect it from water when surfing). Maybe the thing that helped me get back to the dock was simply cracking open the filler cap on the gas tank?????

At this point, I'm ready to replace the fuel line, change out my Pro Comp coils to an HEI distributor, and anything else that I can think of. I will note that I have NOT taken the fuel sender unit out of the gas tank so I don't know if I'd find anything there. Worth a look???