Surging and Detonation

Sounds like it's not getting enough fuel on the top end. Let us know what the plugs look like and if any stand out from the others. Pics are great too.

Those protechs have a bad rep as well.

For now, pull the plugs. Otherwise I'd wait for a few more guys to offer some help. I only know what I've read about the protech system where others have dealt directly with it. Maybe get a few shots of the engine too.

If it turns out to be a fuel problem/shortage, most start at the tank and work forward. It could be a stuck check valve, bad fuel line(pinhole, dryrot), clogged fuel filter or one full of water, a clogged inlet screen at the carb, or simply mal adjusted floats.

Don't get in a hurry and don't start throwing parts at it. Lots of guys here know way more about this than I do, but you may not hear from many on a Sunday.

Here are the plugs starting from right side (driver side) front to back then left side front to back.

Pics of motor to follow in a couple minutes.

I thought fuel related as well, it's just the pinging scared the crap out of me!

ANY help is GREATLY appreciated! Not too much of a hurry, just want it running fine before storage in another couple weeks.

Got a valve cover oil leak on the port side?

They're clearly not burning evenly which may point to what Eric posted or the protech as they aren't the same on one side or the other.

Buffalo,

I don't think the valve cover is leaking. The residue you noticed seemed to be leaking out the bottom of the spark plugs. Could it mean they weren't on tight enough? I know they are supposed to be torqued to only 15ft/lbs. I did NOT notice any of the port plugs come off any easier suggesting that they were loose.

kvand347 wrote: Here are some pics of the motor. Please let me know if anyone sees anything out of place

Flame arrestor bolt.

I took the bolt off with the PCM plastic shroud so it would expose the carb. How do you clean the flame arrestor? Manual says use solvant. What kind?

kvand347 wrote: How do you clean the flame arrestor? Manual says use solvant. What kind?

I use brake parts cleaner and spray from the inside out and follow up with air. That's not your issue now though.

For those with the smaller diameter brass arrestor; they fit nicely in a coffee can.

History of boat:

I've owned (or should I say my bank has owned ) for 2 weeks. It was purchased from a guy who had it for 2 years. His reason for sale was to use the money for finishing his basement. Since he works nights, he was not able to use the boat as much as he would have liked. He only had it out once this year, 4th of July weekend.

The person that owned it before him apparantly had the motor rebuilt. Apparantly his dad is a marine mechanic. There is no documentation whatsoever, but I was disuaded since if its still original it only has 900 hours on her. I have noticed that wires are labeled which leads me to believe that the motor was out at some point.

As for the problem:

I test drove the boat with him and it seriously ran flawlessly except for a loose alternator belt squeeling on start up which I've since fixed. I had it out last weekend and it ran pretty good. I noticed it bog down on our ride and not want to get up and go, but found the fix to be the negative wire coming loose on the side of the carb (not sure what it is powering). I attached it and off we went!

I took it out yesterday since I flushed the tranny and wanted to get the level correct (valvoline dex/merc). It started right away but didn't want to idle at first (I assumed cold weather). Once it started to warm up a little I was able to put the throttle completely in neutral and it idled for about 7 minutes before we took it out. Once tranny level was corrected, I proceeded to do a couple hole shots. First one was good. Second one the motor bogged down and I heard the popping. Brought her down to idle and she was fine. 3rd hole shot was the same as the second, except this time it bogged, surged forward, bogged again, then popping noise. I powered down and took it home.

BTW--You can only imagine how my wife feels about all this!

kvand347 wrote: found the fix to be the negative wire coming loose on the side of the carb (not sure what it is powering). I attached it and off we went!

That's the choke and I bet you're right about the bumping around on the way home. It's gonna be crud in the fuel system I bet.

eric lavine wrote: maybe a crap shoot on the Pro-tec, but ive heard no one complain that swapping it over to a conventional distributor, and that it didnt improve performance all around

Sounds like something to do next season. For now, I'd just like piece of mind that I didn't buy a lemon.

Don,in the fourth pic of the motor. The clear plastic tube running from the fuel pump to the carb. Is there fuel in it? Looks like there may be fuel in that line. Which would indicate a bad fuel pump diaphram.
I have the ProTec on my engine as well....holding my breath every time we go to the lake. So far, so good for now!

kvand347 wrote: For now, I'd just like piece of mind that I didn't buy a lemon.

Reassure yourself and your boss that you didn't get a lemon; really. All you have is a few maintence issues to catch up with. The condition of the plugs says they may have been there a while and so forth.

Don't be upset...just hang around here a while and we'll get you fixed up. Warning, some have cited addiction issues with this site...and you may just catch yourself doing extra maitenance in the future just 'cause you enjoy it.

From here, we'll try to help you eliminate potential problems.

report back your findings and good luck!.

The issue with the E10 fuel is when you let it sit on the tank for some time, the alcohol sucks the humidity on the ambient and then you have water in. It can be as quick as 2 weeks or sometimes it lasts longer. Depends on many factors.

Decomposed fuel will smell like thinner or solvent.

If you use E10 but renew it every 7-15 days you should have no problem using it. So for a quick run you could use it with no problems.

Another issue with it is that the alcohol "cleans" the crud and varnishes built up on the tanks and lines and that makes it's way to the engine clogging filters and carbs. In some boats this clean up process takes more time and creates various episodes with the same simptons until it's all clean and all you will have is to drain water from the filter from time to time, if any's in.