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View Full Version : Need some ideas, got a loud SCREECH again.



HOWARD O
06-27-2010, 08:42 PM
This happened about a month ago also, but I chalked it up to possibly an ignition problem and after I finally got the boat running great, it happened again this evening. My "ignition problem" turned out to be a broken spark plug.

Anyway, I was out running around a bit after supper tonight, went for a 10 mile ride, part of which was in pretty good chop. Coming up river towards home (in smooth water), I had been cruising for about 10 minutes at 3200 RPM and SCREEEECH, hideous sound and I lost propulsion for about 2 seconds. Pulled back on the throttle, it went away and it ran just fine. To my untrained ears, it almost sounded like a spun bearing or something to the effect. It wasn't long enough to determine if the engine had actually cut out or not, but I don't think so, or if it came from the transmission or even the propeller hub. It was pretty unsettling though. Temp and oil pressure were fine, clean fuel, new plugs and even a new ignition. I changed the outdrive oil not 2 weeks ago and also changed out the tranny oil maybe 2 months back. Otherwise, it has been running just great. Have had no signs of the tranny slipping out of the hole either, but I'm easy on it.

If it's any clue, it seems to happen when I am running a constant RPM for a while? 22c, 454/330 TRS w/Merctrans

Open to any ideas? :confused:

Cuda
06-27-2010, 09:24 PM
That tranny had just been rebuilt with an extra clutch installed. I was told it was good to 650 hp. It's a single speed Ford transmission. C6 I think.

Screetchings sounds like a belt.

Check there is clearance between pullies.

It has a Merc distributor and box in it. I'd check the distributor wires, but I don't see how that would make it screetch. It isn't a bearing, they rarely fix themselves.

Good luck!

BlownCrewCab
06-27-2010, 09:50 PM
Does it have some sort of drive coupler? If not then it's probably a Belt, if the belt is not loose then the alternator is momentarily locking up. (or maybe a power steering pump if you have one). but something rubber is spinning unwillingly against something metal. Did you smell smoke?

MOP
06-27-2010, 10:19 PM
When you say you lost propulsion do you mean it felt like it came out of gear???

HOWARD O
06-27-2010, 11:45 PM
It did lose propulsion, but it was one of those things that happened so fast that I couldn't determine where it had come from. However, the first time it happened about a month back, it was for a longer period of time. It definitely lost propulsion that time too and it was almost violent. I really thought I had possibly run aground or hit something underwater. I put it in neutral and it was idling fine. Shut it down and raised up the drive to have a look.....nothing out of the ordinary there. Looked and smelled around the engine, nothing. Started it up and idled a while and all was well. Got up on plane and went the half mile back home with nothing out of the ordinary. This time was much the same as that, but a bit shorter period.

At the time I thought I was either having ignition problems or had some kind of weird thing with water in the fuel. Since then, I replaced the distributor and ignition with a new Pertronix HEI, new plugs and also added a Racor filter. Oh, I just changed the waterpump impeller too. In the midst of all that, one of the new plugs I had installed had a hairline crack. That drove me nuts for a while because I really thought something had happened with the engine. Finally tracked down the broken spark plug and voila, the boat has been running better than it ever has for me. I had easily buzzed up to 62 mph GPS with 4 adults in the boat and had I left it there, would've gone faster easily, but I don't really run it hard like that very often, I'm a cruiser. I was just showing off a little. I've been really pleased the last couple weeks. Then this shreek happened again when I really had thought it was taken care of.

I have had no issues with the tranny at all. Sometimes if I'm not trimmed inand goose it too much out of the hole, it may slip a hair, but I back out and that's only happened rarely. It shifts great and doesn't display anything weird. I'm always pretty easy on the tranny. I haven't removed the outdrive to do anything internally like u-joints or such, but I did change the oil a few weeks ago. The old oil was very clean, didn't smell and no water in it.

Cuda is sure right about bearings, they definitely don't fix themselves. I was only trying to describe the sound. It's bugging the heck out of me because it's only happened twice and the boat is running with no issues right now. I'll go through the belts again but I did that when I put in the new impeller. The alternator belt was a bit loose, but I tightened that up at that time.

Now let me run this by you real quick because I have a hunch that BlownCrewCab has touched on. I've been suspicious of the alternator since I've had the boat. My voltage gauge is pegged and drops considerably if I put a load on it with anything like trim, lights, blower, etc. I've asked about this last year because I know it wasn't always like that and it was good when Cuda owned it because I've seen a photo of the gauge when he was running the boat at 60 mph. Let's say the alternator IS locking up temporarily like CrewCab suggests. That would kill the ignition, no?

Geez, I can't believe I just wrote all of that...... :boggled:

mrfixxall
06-28-2010, 12:13 AM
loosen the alternator belt and spin it by hand,,it should be nice and smooth with no noise what so ever..i have seen them lock and kill a motor at idle,,when they go and your volt gauge is pegged then its throwing a/c voltage at your electrical system and will blow your light bulbs..

Cuda
06-28-2010, 06:57 AM
I didn't notice on the first post that you change the ignition. That would be the usual suspect for breif power loss. Those problems often fix themselves. It's usually a loose wire on either the coil or the distributor.

Might want to follow Fixx's lead. I've never fooled with alternators much. Remember, that alternator is 28 years old.

HOWARD O
06-28-2010, 07:38 AM
The very reason I had changed out the impeller was because I was getting a slight what I thought was a belt screech at idle that went away with a tiny increase in RPM. Although the impeller was missing a blade, it wasn't the impeller making noise, it was the alternator belt. I tightened it while changing out the impeller. The alternator seemed to turn free and smooth, but I was so suspicious of it at the time, I actually searched on the 'net for a replacement. True enough, it is 28 yrs. old and doesn't owe me a thing. They aren't too expensive.

LKSD
06-28-2010, 08:02 AM
Is it possible that you cavitated your prop? Depending on your prop, trim angle, load & water conditions you may have broken its bite loose in the water. It can sometimes make a noise & speed or motion loss for a brief period of time. Then once you slow down, alter trim or stop and restart everything is fine again..

If you did do that then it may just be that you either need a different prop or more seat time..

;) Jamie / Lakeside

Chris Duval
06-28-2010, 08:08 AM
Howard, I have the same engine set-up as you (not that this really matters), but two years ago I had the same issue and it was bad bearings in the alternator. Don't know if that is your problem, but something to check. Good luck, Chris Duval

HOWARD O
06-28-2010, 08:49 AM
Howard, I have the same engine set-up as you (not that this really matters), but two years ago I had the same issue and it was bad bearings in the alternator. Don't know if that is your problem, but something to check. Good luck, Chris Duval

Thanks Chris, that helps a lot. I am leaning towards the alternator as the culprit.

mattyboy
06-28-2010, 09:02 AM
Howard,
that happened to me on my 16 in lake george a few years back , the water was rough and i busted one of the ears off the alternator it shifted out of alignment causing the belt to screech.

BUIZILLA
06-28-2010, 09:08 AM
i'd be very surprised if it was the alternator..

fogducker III
06-28-2010, 09:49 AM
Just a thought, are your belts tensioned correctly? I take it you have individual belts and not a serpintine set-up?

My serpintine did the exact same thing, loud screech and when it slips it obviously is not driving any of the engine components, adjusted the tensioner pulley and all was well.....:crossfing:

HOWARD O
06-28-2010, 12:04 PM
i'd be very surprised if it was the alternator..

Jim, because it's intermittent and if it was shot, it'd be doing it constant? This thing is the old kind with the VR piggybacked on it.

Fogducker, the alternator belt is tight and I double-checked it this morning. I will say it was run with the belt fairly loose for a while. When I started it this morning, I had a momentary squeel at idle that went away immediately, not even long enough to get back there to determine where it was coming from. I was having that squeel during the time this happened a month ago. My first thought was the impeller making a noise and I replaced that. Squeel didn't return, until yesterday. The alternator spins freely by hand...very freely, with no slop in it either.

I don't know, maybe I'm barking up the wrong tree........again. :boggled:

HOWARD O
06-28-2010, 12:05 PM
Just a thought, are your belts tensioned correctly? I take it you have individual belts and not a serpintine set-up?

My serpintine did the exact same thing, loud screech and when it slips it obviously is not driving any of the engine components, adjusted the tensioner pulley and all was well.....:crossfing:

I'm going to clean up the pulleys real good and replace the belt for good measure. At least that's a cheapy!

Cuda
06-28-2010, 12:12 PM
The very reason I had changed out the impeller was because I was getting a slight what I thought was a belt screech at idle that went away with a tiny increase in RPM. Although the impeller was missing a blade, it wasn't the impeller making noise, it was the alternator belt. I tightened it while changing out the impeller. The alternator seemed to turn free and smooth, but I was so suspicious of it at the time, I actually searched on the 'net for a replacement. True enough, it is 28 yrs. old and doesn't owe me a thing. They aren't too expensive.
I just sold one for $25.

Cuda
06-28-2010, 12:14 PM
Just a thought, are your belts tensioned correctly? I take it you have individual belts and not a serpintine set-up?

My serpintine did the exact same thing, loud screech and when it slips it obviously is not driving any of the engine components, adjusted the tensioner pulley and all was well.....:crossfing:
It's V belts. If the belt wore it's way to the bottom of the pulley it will screech.

Cuda
06-28-2010, 12:19 PM
Jim, because it's intermittent and if it was shot, it'd be doing it constant? This thing is the old kind with the VR piggybacked on it.
Fogducker, the alternator belt is tight and I double-checked it this morning. I will say it was run with the belt fairly loose for a while. When I started it this morning, I had a momentary squeel at idle that went away immediately, not even long enough to get back there to determine where it was coming from. I was having that squeel during the time this happened a month ago. My first thought was the impeller making a noise and I replaced that. Squeel didn't return, until yesterday. The alternator spins freely by hand...very freely, with no slop in it either.
I don't know, maybe I'm barking up the wrong tree........again. :boggled:
I'd be surprised it it was the altenator too, but what do I know.

I had a guy across the street (a friend of my neighbor) tell me he fixed 6 engines by replacing the coil. I've got a whole garage full of coils where I convinced myself it HAD to be the coil. It never was once. I told that guy he probably fixed a bad connection when he replaced those coils. He was drunk as a skunk when he tried to tell me that. All the coil is is a winding of wire. Very little can go wrong with them.

HOWARD O
06-28-2010, 12:20 PM
It's not all that worn, but it has some wear. Here I am again over thinking and jumping at the wrong conclusions when it could be just the belt. :bonk: Lack of experience I suppose. But the upshot is that I am gaining some! :cool:

HOWARD O
06-28-2010, 12:24 PM
I think I'm dumb enough to keep throwing parts at a problem, just not rich enough to do it!

Once again, thanks for the sage advice! :yes: