1999 VP 5.0GL SX - stuttering, died, bendix gear won't engage now

[Augoose]

Well,
For all the times I've towed others in, it was my turn today.
In an attempt to troubleshoot, here's what happened....
The boat ran normally today at first. We ran about 40 minutes, moored the boat in rough chop with the stern towards land and the bow into the wind. The chop was about 2' swells on average and the boat was bouncing around quite a bit for several hours.
Went to leave and the boat started normally. Idled away and ran for about 20 minutes at headway speed, just cruising. Went to increase throttle and the boat stumbled a bit.
This stumble has happened before - maybe once every 5-6 times out. The stumble in the past has always cleared up when I eased off the throttle and then got back on it again. Usually it was when I was getting on the throttle hard pulling a skier. It was the same symptoms today. I didn't think much of it other than making another mental note to figure out what's causing it.
So we continued, running the boat at about 2,500 rpms for about 20 minutes. Everything seemed normal and then the boat started stumbling again. At the same time, the radio started cutting out. The boat then seemed to enter what I can only describe as a limp mode. The boat would run and sounded like the engine ran normally, but only if you kept the rpms low, say around 1,500. As soon as I tried to increase throttle it would stumble again.
Oil pressure stayed normal, engine temp stayed normal, but the voltage was reading 11.7v according to my fish finder.
After another five minutes or so while running in the "limp mode", the engine stopped. When I attempted to start it, it sounded like the bendix gear would only spin and not engage the flywheel. I tried tapping the side of the solenoid and it didn't do any good.
So, I was initially thinking hydro lock. However, I think that is unlikely because ever since I started noticing symptoms, the engine never suddenly died and in general I never allow the stern to get swamped, such as cutting out the engine while on plane. Even when exhibiting symptoms, the engine would run well and it "sounded" strong until I asked for more throttle. Then it quit.
Now I'm thinking I have a bad or failing alternator or a bad connection somewhere. Considering my radio started having issues at the same time the boat when into "limp mode", I'm wondering if for the last several months my alternator hasn't been keeping up with charging the battery properly and when I'm at open throttle, there is more demand from the electrical system than it can deliver, such as the operation of the fuel pump? The engine then starts stumbling (weak spark), the radio begins to cut out, and then it dies completely? Then when I attempt to re-start the engine, only the bendix gear spins, possibly because the solenoid has failed too? Is that just a coincidence?
In an attempt to troubleshoot the electrical system, I've put the battery on a maintainer. The plan is to attempt to start the boat again on muffs to see if a charged battery changes the symptoms. I then plan on pulling the alternator and taking it to one of the auto parts stores for them to test since the electrical system was reading 11.7v.
Thanks for any suggestions or help

 

[dypcdiver]

Sounds like the battery is not putting out full power due to possibly a lack of charge, loose/corroded terminal, battery isolation switch etc. Does your radio go through the ignition or is it wired directly to the battery?
I once had a spring loaded isolation switch that had become a little dirty and whilst supplying 12.6 V and lighting up all instruments, as soon as a demand was put on it the voltage dropped to zero.

The starter if not supplied with a good voltage can frequently not rotate fast enough to throw in the bendix.
Let us know how you fix it please.

 

[Augoose]

Thanks for the response. I've got two batteries in parallel on a mechanical switch. No isolator. The radio, fish finder, etc all run direct through battery #2, which is a deep cell. Battery #1 is the starter.
Glad you brought that up... I was on battery #1 when the engine started stumbling and when the radio started malfunctioning. If battery #1 was failing because of low alternator output, why would the radio start exhibiting problems at the same time the engine started stumbling if the radio is on battery #2?
Unless a bad ground somewhere is the common problem?

 

[Augoose]

Well I pulled the plugs and got a ton of water coming out of the #7 and #5 cylinders, followed by somewhat less water out of the #8 and #6. #'s 1 and 2 had no water. #'s 3 and 4 had very little. Once the plugs and water were out, I cranked the engine by hand to rid the rest. Then I sprayed WD-40 into each cylinder and then manually cranked it some more. I then used the starter to turn the engine over, so my starter appears not to be the problem anymore.

So, I'm trying to figure out if I had an electrical problem which caused the boat to die suddenly and take water up through the exhaust or whether I have a water immersion problem which is what caused the whole ordeal to begin with.

When I was moored at the beach, I trimmed up nearly all the way because we were in the shallows. The boat started fine after leaving the beach and ran like I said above for at least 30 minutes. I can't see how water was in there from being moored and yet the engine started and ran at low rpms fine?

Then when we tried to accelerate the first time, we first noticed the stumbling and the radio cutting out.

If you dramatically slow the boat down after say pulling a skier but continue running the engine, can water work its way up past the exhaust? What other ways can water work its way in? Considering the majority of water was in the #7 and #5, what would that mean?

Maybe all this water entered the engine after the final stumble where the boat died and I still have just an electrical problem - such as the alternator failing and the fuel pump stopped?

My plan is to put the plugs back in and attempt to run the engine for a bit and then change the oil and see what it looks like.

Other suggestions?
Thanks

 

[Saline Marina]

This seems like a remote possibility, but if you have an intake casting which is compromised (rotted and leaking in a thin spot) between water jacket and the plenum that would cause poor running by virtue of now having an air/fuel/water mixture that's barely combustible and having the excess run into various cylinders when stopped. As you crank & run more and more water gets pushed into it as well in this scenario. I've never seen the intake casting on a 5.0GL but have had the same part on a 4.3GL in my hands more than I'd like. That one has a very large water passage in it that bathes the lower side of all of the intake runner system.

 

[Augoose]

Thanks Saline for the suggestion. I think the water came up through the exhaust because it's back up and running now on muffs, seemingly with no water infiltration.

Sorry for all the posts - here is where I am now.
I reinstalled all the plugs and took the alternator to a local auto parts place for them to test it, but unbeknownst to me they say they can't test marine alternators - so that didn't work. I did however clean the connections and found several posts a bit loose.

I put the boat on muffs and attempted to start it. It sounded horrible as it cranked over for about 10-15 seconds, presumably pushing out all the WD-40 I sprayed into each cylinder. After some rough sputtering, it cranked and started idling normally. I was able to work the throttle between 1,000 and 2,500 rpms with no issues.

I went through a couple of start/stop cycles and every 4th or 5th cycle I heard a bit of scratching or grinding while the starter was turning. Additionally, during one of the test cranks the starter just spun and I got the same sound as described in the initial post. Thinking I had water in the cylinders again, I checked the spark plugs but they were fortunately dry. I manually turned the engine over a bit and tried the starter again and it started normally.

I ran the boat again for about 15 minutes and did several start/stop cycles. Other than the occasional extra noise when starting which I presume is because the starter was damaged during one of the attempts to start the boat out on the water when it was hydrolocked, each time the boat started fine and ran fine.

So, I'm thinking I had an electrical issue out on the water yesterday which caused the stumble. I presume that if I was taking on water into one or more of the cylinders while underway, such as from a bad exhaust manifold or riser gasket, the boat would do more than just stumble and immediately recover. This stumble has always been just occasional, except for yesterday it was severe.

I presume the last stumble yesterday caused the engine to stop completely, a wave then hit the back of the boat just right (it was super choppy and windy) and water came up the exhaust and into a few of the cylinders. I then attempted to start the boat and whirrrrrrrrr.....the starter just spun because you can't compress water. Sound plausible?

I checked the oil on the dipstick and it wasn't cloudy whatsoever. Should I change the oil now or run it for a little while longer and then change it?

I also plan to revisit every starting/ignition circuit contact at the rear of the boat in an effort to prevent future stumbles.
Thanks all for the help.

 

[Lou C]

Normally when you get water in the cyls from bad exhaust its after sitting, not running because the exhaust pressure pushes it out when running. If water gets in the cyls when running, that can be a bad head gasket, cracked cyl head or block (both unlikely but possible). While a rotted out intake manifold is a remote possibility, they usually rot out right under the thermostat housing which would put water right in the cam valley...into the motor oil but not cyls. I'd keep running it on the water hose and check for water in the cyls...also...check under the valve cover via the oil fill opening...for signs of milky oil...that much water...some must have gotten into the oil...so change it....

Fresh water or salt? If salt when were the exhaust manifolds and elbows last replaced? Any sign of leakage around the gasket between the manifolds and elbows?
Does it ever diesel when you shut it off (attempt to keep running after switching off the ignition and before stopping run backwards for an instant)? That for sure can pull water up the exhaust. In this case it does not sound like you had a hydrolock after sitting but when it stalled, if it dieseled, that could explain what happened.

 

[Augoose]

Thanks Lou.
I assumed that the exhaust from a running engine would push the water out, but I wasn't sure.
I think the cracked block or head is unlikely as its never even come close to overheating and running in the driveway for about 30 minutes left no indication of water in the cylinders. Its also good to know the other ways in which water could come in and then compare those possibilities to other indicators I see.
Its been in fresh water since 2012. Prior to that with another owner my understanding it was in brackish water however it only had 123 hours on the engine when I bought it. It now has 300.
The exhaust manifolds and risers were last checked a few years ago and there has been no indication of rust or leakage that I can see around the manifold or elbows. I need to check them now.
It has never dieseled - always been a clean shut off.

I'll change the oil as soon as I can and continue running the boat in the driveway.
I'm also worried I also broke some teeth either off the starter or off the flywheel (hopefully just the starter), as during one of the start/stop testing cycles, the starter just spun. Plan is to pull the starter and then get my head down in the bilge with a flashlight and inspect the flywheel while someone manually cranks the engine over.

Thanks again all

 

[Augoose]

Just another update. I pulled the risers, no indication that the gaskets have failed or that water has been working its way into the gas only section of the manifolds.
As stated above, the oil on the dipstick appeared good, however it was high - indicating that water had made its way to the oil pan. After draining the oil, it was indeed milky. I ran through about 8 quarts of the cheapest oil I could find by way of "flushing" the system and then pumping it out. I'll change the oil filter this weekend and run the boat again for a bit and then change it one last time.
I also pulled my starter and noticed that as soon as the first bolt was out, the starter was already loose. Not good. What was good however was the condition of the flywheel, so that was a relief! I manually cranked the engine over with a 1/2 socket on the bell housing in front of the water pump and the teeth all looked fine.
My plan now is to install a new starter, change the oil filter, replace the manifold gaskets (since I opened them up) run the boat on muffs again, and then drain the oil one last time which will hopefully rid the system of chocolate milk.

Thanks again to all of those on the forum who post such great information. Without this resource I'd be boatless by now for sure.

 

[harojs]

Does your 5.0 have "Flappers" at the top of the Y-pipe below the elbows? My 5.0L VP from 1995 does. It is possible one or both of the flappers have failed and fallen down into the Y-Pipe. That could then allow water back up to the manifolds in certain cases. That happened to me. I used a scope to find them down in there. You might be able to use a coat hanger to retrieve flapper from the top after removing elbow, or else you need to pull the leg to retrieve fallen flapper from exhaust bellows. I heard that VP discontinued the flappers after some model year. I would check your model specs.

 

[Augoose]

My understanding is that Volvo did away with the flappers in '99. The boat has 300 hours on it and I've never had this issue before nor any overheating issues. I think a bad connection at the alternator caused the boat to die (fuel pump stopped) and a surge of water to slap the back of the boat, causing the water ingestion. At least that's what I'm telling myself anyway.
I'm reinstalling a new starter today, fresh oil, and new manifold gaskets.
A water test this afternoon will tell.
thanks for the help

 

[Augoose]

So the water test went well. New starter seems to be fine. Never failed to start and I ran the boat 2,500 rpms and below for about an hour. Mostly idling as I wasn't sure how much milky oil was still in the system.
For anyone suffering similar symptoms, in total I did three cycles of pouring in about 3-4 quarts of oil and then pumping it all out in an effort to draw out all the milky oil. I replaced the oil filter after those three cycles and it was of course full of milky oil. I then added fresh oil and ran it as I said above for about an hour on the lake. Brought it back home and pumped out all the oil again into a clear container. Looks tan to me - like good oil on its way to being black. If the water intrusion was caused by something else such as a bad manifold gasket or a bad head gasket and not just water coming in through the exhaust from a sudden stop, I feel like I ran the boat long enough that I would have seen evidence of a failure in some area.
I'm going to replace the oil filter one more time and put in some fresh oil and run it for the rest of the season. I'm also going to replace the alternator as I don't trust it - I think that's what got me in this mess to begin with.
Hope everyone is enjoying their Saturday.