Losing Power - After two hours

[Eric 3.7LX Alpha 1]

That first pic looks like you have water in that gas. Did you let it sit to see if it separated?

Yeah, your sender is probably bad. That comes after "is all my teak oiled?" In priorities for fixing on my boat.
Would still like a vid, since if your engine is slipping we're still chasing the wrong problem

I agree. Good ol ethanol strikes again. Take a bit of that cloudy gas out of the cup and put a tablespoon or so on something that can take fire, and try to light it with a grill lighter, I bet you can't.

 

[Grub54891]

Didn't read the entire thread, try disconnecting the tachometer. They can cause issues when they go south.

 

[Kconleyk]

That first pic looks like you have water in that gas. Did you let it sit to see if it separated?

Yeah, your sender is probably bad. That comes after "is all my teak oiled?" In priorities for fixing on my boat.
Would still like a vid, since if your engine is slipping we're still chasing the wrong problem

It say for about two hours while we ran out and grabbed some dinner with friends, came back and it looks very much the same, the filled cup looked dark Yellow and the half filled cup very clear with a lot of black sediment in it, that didn't look like metal but more dirt.

 

[Kconleyk]

I agree. Good ol ethanol strikes again. Take a bit of that cloudy gas out of the cup and put a tablespoon or so on something that can take fire, and try to light it with a grill lighter, I bet you can't.

So I have half a tank of gas left, should I pump it out (i just added stablizer to it) and just start fresh? I don't have anything big enough to old all that gas that is in there, because I believe it would be about 35 gallons.

 

[Eric 3.7LX Alpha 1]

I would try the burn test, a tea or table spoon in a metal bowl, or if you don't have one, maybe cut the bottom of a soda can open to burn it in. If you can light it, it wouldn't worry me as much. If you can't light it, it would be in your best interest to get it out and start fresh. It's only going to get in your carb and make running the engine tough. If it doesn't burn, you can try draining out 5 or 10 gallons and see if it gets better, try lighting a small bit again in a bowl. If it doesn't smell like gas it's not a good sign.

 

[dingbat]

Some pretty crazy baseless theories being thrown around.

Extenuating circumstances:
New boat owner
Prior Maintenance unknown
23 year old boat

Symptoms:
“2 hours” to manifest
Momentary loss of power
Unregulated Surging
Seems to resolve itself

Findings so far:
Fuel lines well past life expectancy (23 yro)
Anti-siphon full of “grass”
Fuel filter has hose liner in bottom of bowl
Water in fuel filter

You find a solution to solve or explain each of these problems you have your answer.

Pretty apparent the fuel delivery systems is compromised in some way.

inspect the inside of the fuel tank
Replace fuel lines
Replace fuel filter (10 micron) if not already done so.
Pull fuel line at carb to check for any in-line screens (stick and stone catchers)
Verify fuel pressure is to specification.

Rebuild carb or at least check to make sure float and or needle valve isn’t clogged or sticking.

 

[Kconleyk]

Update:

After changing Anti Siphon Valve and Fuel Water Seperator

Took the boat out last night after work, hoping to be out for two hours and run it wide open as long as possible to get the engine as hot as possible. I dropped it in the water and the tide was low already and going out, so I only got 90 minutes of run in before I was worried about the ramp getting to shallow, which happens at my local ramp.

Put the boat in the water, and it fired up faster than ever, normally I have to give it some throttle and it will fire, I turned the key and it fired up instantly. Ran perfectly for 90 minutes, once I got out of the landing and into the river, I ran it wide open the entire 90 minutes.

I don't want to say anything is solved, but I am glad it ran so great. Ran smoother, hit two miles an hour higher than I have hit before.

The tach for RPMs is definitely not functioning right, it seems to settle at 4,100 rpms when running on plane, but it's weird it goes backwards to get there, but the engine seemed to be running fine so that seems to be a tach issue not a an engine issue?

 

[Kconleyk]

Another update.
Happy Father's Day to everyone. A little frustrated but new issues or reoccurring issues below. I know I bought a used boat but it ran perfect at the test drive and was hoping for something safe to take my daughter on, but at the end of the day it is what it is. Taking it to a mechanic this week, cause I'm over my head in what I can do at this point.

Took it out today, after starting right up last time, it took a minute to fire today (fresh gas). Road it for an hour, road perfectly.

Rafted up with friends for three hours, turned battery off, put engine in up, and just relaxed for a few hours.
Went to leave, boat fired up, as I was pulling away it felt sluggish. Got far enough away from raft up that I could pick up speed, and had no power, could putt a along around 7mph but that's it.

Turned around and saw water coming out of engine housing and opened it up and it was about a quarter full of water.

At the same time I realized I could turn to the left easily, but turning right was impossible, the wheel was hard almost like it was stuck.

Got most of the water out, and cruised home at 7mph, was about three miles away. About half way home, out of nowhere the boat started working fine again, both power and steering.

All three seem like separate issues, water in engine compartment, steering and power but I'm frustrated at this point don't want to have my daughter stranded on the water. So to the mechanic I go but don't want to get ripped off because I don't know what to look for them telling me. Frustrating but was a fun day before the issues.

Still ran perfectly at first just like every time, this time however half way back after no power issue, it randomly kicked back in and started firing again.

 

[Kconleyk]

So it's been a while since I updated and still stuck, so figured I'd update.

For anyone who doesn't want to back read. Boat fires perfectly, idles great and has good compression. Originally after a few hours of running the boat would lose power under load, would never cut out but lose power while under current load. If I put it in neutral engine would idle fine and sometimes it would go back on plane under load, other times it would have no power or very little power.

I replaced the anti syphon valve, new prop and hub, and water separator. Same occurrence.

Took it to a mechanic, who did new bellows, a serotine belt, electric fuel pump, engine coil, distributor cap and plugs. Took it out and same problem. Lately it happens with in minutes or 30 minutes of running it.

The mechanic went for a ride with me, prior he was so sure he knew the issue he did the work with out test riding it (not happy about that nor did I know this)

During test ride I went with him, and we lost power with in 20 minutes under load, this time the motor started cutting out if we pushed it to hard in testing while it had no power. Once it backfired and spun the new belt off, luckily we got it back on.

His new claim is the exhaust manifold is bad and leaking water, as well as the risers, and that is putting out the spark to the engine. Would the engine idle fine if this was the case. He is saying as the engine gets hot (days are hotter now then first occurrence of issue so engine heats up faster he is saying) and the manifold is expanding and not air tight.

Thoughts?

I'm so annoyed I'm about to sell it for a loss and just move on, I paid good money for it to do the same exact thing.

I know boats are being out another thousand, but to try and fix an issue and spend good money, only for it not to be that is frustrating.

I keep asking him if it could be a carb issue and he says no. I knew this guy from school and he is a straight shooter but he almost seems like he is guessing but trying to sound confident. Thoughts on what he says now?

 

[Paintman1960]

Remove them and look inside ports, See rust?, might have a issue
Test them ..

 

[Grub54891]

At this point It wouldn't hurt to have the carb rebuilt. Many mechanics are afraid to touch a carb as they are complicated. I myself have no problem rebuilding them. The only thing that will happen if you do is get rid of doubt that is the issue. Checking the manifolds is also a good idea.

 

[Eric 3.7LX Alpha 1]

Get a temporary fuel pressure gauge inline between the fuel pump and carb inlet and run it. See if pressure changes when you have an issue.

 

[glennj3]

I’ve read each thing you all wrote. I sympathize with your frustrations & feel your pain as I’ve had mine. I anticipate finding out the answer.

 

[zellerj]

Just a safety note for a new boat owner. Never swim with the engine idling. Boats have been know to jump into gear, or others in the boat have bumped the shift lever. Always have the engine off when people are climbing up the stern swim ladder.

 

[Paintman1960]

Just a safety note for a new boat owner. Never swim with the engine idling. Boats have been know to jump into gear, or others in the boat have bumped the shift lever. Always have the engine off when people are climbing up the stern swim ladder.

Absolutely!!!