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3rd Shredded Alternator Belt - Islandia

Daxxer

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Hey all!

Just wondering if anyone has some ideas on my belt eating issue on the Mercury 240 efi on my 02 Islandia?

2nd belt I've put on in several months and about 20 hours on the water. When I bought the boat, one of the seller's supposedly great features was that he just replaced the belt ... so there've been at least 3 replacements, probably more. Everything seems to be hunky dory after replacement for a while.

Here's what went on last time out, and what I've done so far:

On way out there was a low chirping beep while idling down to the river but it eventually went away and we were jamming along for 15 min or so. Then came the loud incessant beeping that I've heard before and the no power from throttle. My buddy thought it was overheating ... I knew the sound to be low battery. Opened the compartment and sure enough the belt was once again thrown off and there were only 1 full and 1 half belt treads left. Only a day earlier I had been cleaning the crap from the compartment and had found some pieces of belt. Figuring they were from previous belt shreds I simply tossed them. Looking back I guess they were the other part of the current belt and it had been running on only 2 treads.

We limped home with the incessant beeping. I pulled both batteries and had them charged and tested. Both good. So what is it? I don't see how the belt alignment could be off as there seems to be no adjustment?? The tensioner pulley rocks a hair but seems fine. I guess I'll replace it just for kicks ... doubtful, but maybe bearing? Alternator seems fine as the beeping issues start apparently only when the belt is down to the last 1 or 2 treads and probably losing traction. Seems to be somehow slipping a tread at a time.

Dunno ... need greater and wiser minds to figure this one out!

Thanks for any thoughts,

Craig
 

Boat Crazy

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My guess would be tensioner pulley bearing might be bad causing it to periodically locking up and causing belt shreading. I had a belt tensioner go bad on my f350 and it shredded a belt. Had tensioner replaced and problem solved. Does your alternator pulley spin freely with alternator belt off, or does it seem to stick?
 
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Daxxer

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it seems to spin fine. Just looking at it though, it seems to be be a 1/8 to 1/4 inch below other pulley tracks. No way to align belt treads that I can find. If it is off even a little bit I'm thinking the belt treads start walking and essentially break off individually,
 

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Have you double checked that you have the correct belt?
 

Dough

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My 350 i/o gets a new one every year now due to the same problem. I side with murf, make damn sure it's a marine belt. My boat will shred an auto belt in about the amount of time your talking about.
 

Daxxer

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Mine have been the friggin expensive Quicksilver/Mercury Marine belts.

Thanks for the responses guys, I appreciate it. I'm definitely frustrated and researching and coming up with little ....
 

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Would a broken motor mount or two cause some twisting? I would think that the entire engine would move and the belt/pulleys not be affected.
 

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Are you the original owner? I ask because I had an 03 seadoo x20 with a v6 240 merc power plant and pump, I don't recall that it had an alternator. Mine and the 175 hp version I'm a another jet boT I owned had stators not conventional alternators. Maybe a previous owner of your boat modified it? I'm just putting another possibility out there.
 

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after a little digging I found this great engine manual for you, It does appear to have an original alternator page 2a-16 and after a quick google and looking at the sea-doo site at least one member noted his alternator "locked up" and wasn't spinning. I would suggest you make sure the alternator and pulley spin freely and doesn't have any wobble to it as a starting point,
sorry we can't be more exact with our answer,

http://boatinfo.no/lib/mercury/manuals/240efi_jetdrive.html#/54
 

Scottintexas

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also found this, so be sure the air compressor and any thing else is spinning freely,


http://www.jetboating.net/jetboating/common/forums/threadview.aspx?forumid=1&page=1&threadid=13632

OK, here's some more data. It really is an air compressor, but it IS fuel-related... May 12,2008 11:51:02 PM GMT

The way the DFI system works is by using pressurized air to inject the fuel into the pressurized cylinder. They claim to get better atomization because air is pushing the fuel rather than just shooting pressurized fuel alone. Here's an excerpt:

-----
A belt-driven air compressor pressurizes the system for air and fuel delivery, and an advanced Power Control Module (PCM) precisely monitors the air/fuel ratio being delivered based on data from many sensors located throughout the engine. A PCM-controlled electric oil pump delivers raw two-stroke oil to the needed bearings, then combusts it afterward. The overall result of this technology is an engine that will burn roughly 40 percent less fuel than previous generation fuel injection systems while running with virtually no characteristic blue smoke. It’s a very efficient and economical system to run, but what are the drawbacks?

One of the main drawbacks to direct injection is the reliance on an air compressor for system pressure. The compressor is driven off the engine flywheel by a large serpentine belt, and since valves regulate system pressure during operation, the air compressor runs full time. This creates two possible problems from a performance standpoint. First are the parasitic power losses from driving a power-robbing air compressor, and second is the RPM limit that must be imposed by the compressor to maintain engine reliability.
-----

So it really is an air compressor, in this case used to inject the fuel rather than just pressurizing a fuel-only stream like gasoline EFI or diesel. Verrrrrry interesting.
SeaDoo - 2001 - Challenger 2000 - Merc 240 EFI Reply to this message
 

Daxxer

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Thanks for the ideas! To answer the alternator question, yes I do have an alternator on the 240 efi JD M2, and yes the pulley spins fine. Appearance of the alternator is definitely old but again the alt pulley spins ok. The tensioner pulley spins fine also.

I do notice that, apparently by design, the belt comes within a whisker (and I mean close) of the crank sensor which is mounted with 2 small bolts right next to the flywheel. It is not positionable, but it does have some sort of mfg indentation on the top half nearest the belt which allows the bottom half of the belt (2 ribs) to pass freely by. It is a paper thin pass and makes one think about some sort of situation where the belt could bow for a split second, hit it, and shred the closest belt rib. Probably not the issue, but damn it's close.

I did find out the mercury belt I shredded had a 1 yr warranty. Took it back to the dealer who ordered it and they gave me a hard time that it must have been my fault, but finally called Merc and sent the belt pieces back for replacement of this $70+ item. Why would they give me hassle? Does merc deny warranty claims? How can anyone tell how a belt broke with just a few scraps left?

Also, I have been told that there is an automotive belt that is usable for this engine and works fine and costs $10 or less. Just don't know the number and can't find a cross reference for ANY Mercury belts anywhere. Did they somehow shut down cross referencing their products
 

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Also, I have been told that there is an automotive belt that is usable for this engine and works fine and costs $10 or less. Just don't know the number and can't find a cross reference for ANY Mercury belts anywhere. Did they somehow shut down cross referencing their products
Post up the merc belt specs/item number etc....we have some great internet sleuths here that might be able to dig up the automotive equivalent for you.
 

Speedling

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The belt probably shakes and bows a lot more than you think!
Especially as time goes on and things become slightly unbalanced. Just bring the belt into an automotive store once you get the marine one and they will match it up for you no problem.
I don't think there should really be a huge issue with a non marine belt other than the fact that it may not last as long. Buy 3 and keep them on board with a tool to change if you're that worried about it.
Be sure that everything spins as it should. With the motor running, check again and watch that everything is spinning. Sometimes in a dark engine bay this is hard to see, but putting a little dot of white out or something on the pulley and letting it dry before you spin it will let it be more visible. Obviously, it should be a constant visible circular line where you put the dot at 1k rpms or higher. If it isn't, then you have a pulley not spinning correctly.
As for the bolt and sensor that are so close to the belt, I wonder if you could tell us the two pulleys on either side of it? If one is the tensioner then the tensioner may be needing to be replaced as it may just be worn out and letting the belt get to close. If there is an idler pulley, I would check that it doesn't have any slop in it up and down. If so, replace that. If it's a paper thin gap, then you're hitting it. If you're hitting it, you should see it worn down from the belt as well.
 

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Thanks everyone! I did track down a belt with an exhaustive internet search. Mercury charges around $75 total for theirs. I found several iterations at Autozone, Advanced Discount Auto Parts, Oreilly from $8 to $18. Then I discovered Vbeltsupply.com ... yeehah $3.29!! But you need to pay steep shipping for 1 or 2, so order 4 or 5 for the same shipping charge like I did! Part number is 310K4.

I must say however, that the belt seems waaaaay tighter that the Mercury belt. Almost too tight actually ... really difficult to jam it on. The apparently correct mercury/quicksilver 57-828507Q10 belt was a lot easier to install. Soooo, dunno what that will bring, but I spent a couple hours out on the water and examined belt afterwards. Still looks good. The merc belts did last 4 months before shredding so we will find out soon enough if the cheap belts hold up! Good news is that I have a bunch of spares and keep them and a 3/8 socket wrench (to move the tensioner pulley) on the Islandia!

Will update as warranted ....
 

michaelg

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Thanks everyone! I did track down a belt with an exhaustive internet search. Mercury charges around $75 total for theirs. I found several iterations at Autozone, Advanced Discount Auto Parts, Oreilly from $8 to $18. Then I discovered Vbeltsupply.com ... yeehah $3.29!! But you need to pay steep shipping for 1 or 2, so order 4 or 5 for the same shipping charge like I did! Part number is 310K4.

I must say however, that the belt seems waaaaay tighter that the Mercury belt. Almost too tight actually ... really difficult to jam it on. The apparently correct mercury/quicksilver 57-828507Q10 belt was a lot easier to install. Soooo, dunno what that will bring, but I spent a couple hours out on the water and examined belt afterwards. Still looks good. The merc belts did last 4 months before shredding so we will find out soon enough if the cheap belts hold up! Good news is that I have a bunch of spares and keep them and a 3/8 socket wrench (to move the tensioner pulley) on the Islandia!

Will update as warranted ....
Thanks everyone! I did track down a belt with an exhaustive internet search. Mercury charges around $75 total for theirs. I found several iterations at Autozone, Advanced Discount Auto Parts, Oreilly from $8 to $18. Then I discovered Vbeltsupply.com ... yeehah $3.29!! But you need to pay steep shipping for 1 or 2, so order 4 or 5 for the same shipping charge like I did! Part number is 310K4.

I must say however, that the belt seems waaaaay tighter that the Mercury belt. Almost too tight actually ... really difficult to jam it on. The apparently correct mercury/quicksilver 57-828507Q10 belt was a lot easier to install. Soooo, dunno what that will bring, but I spent a couple hours out on the water and examined belt afterwards. Still looks good. The merc belts did last 4 months before shredding so we will find out soon enough if the cheap belts hold up! Good news is that I have a bunch of spares and keep them and a 3/8 socket wrench (to move the tensioner pulley) on the Islandia!

Will update as warranted ....
Thanks everyone! I did track down a belt with an exhaustive internet search. Mercury charges around $75 total for theirs. I found several iterations at Autozone, Advanced Discount Auto Parts, Oreilly from $8 to $18. Then I discovered Vbeltsupply.com ... yeehah $3.29!! But you need to pay steep shipping for 1 or 2, so order 4 or 5 for the same shipping charge like I did! Part number is 310K4.

I must say however, that the belt seems waaaaay tighter that the Mercury belt. Almost too tight actually ... really difficult to jam it on. The apparently correct mercury/quicksilver 57-828507Q10 belt was a lot easier to install. Soooo, dunno what that will bring, but I spent a couple hours out on the water and examined belt afterwards. Still looks good. The merc belts did last 4 months before shredding so we will find out soon enough if the cheap belts hold up! Good news is that I have a bunch of spares and keep them and a 3/8 socket wrench (to move the tensioner pulley) on the Islandia!

Will update as warranted ....
@Daxxer I wanted to know how long the belt from Vbeltsupply.com lasted. I was trying to look for a similar belt for my 2002 seadoo utopia 205 because the one from mercury are very expensive. I wanted to buy 2 or 3 to leave on the boat just in case.
 
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Daxxer

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They last about 5 to 6 trips out for 3 hours or so. I can replace them in less than a minute now that I know the routine! The Oreilly ones seem to last a bit longer but cost 12 to $20. But .... they are guaranteed for a couple years!! I've already brought one shredded belt back for free replacement!
 

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@Daxxer I wanted to know how long the belt from Vbeltsupply.com lasted. I was trying to look for a similar belt for my 2002 seadoo utopia 205 because the one from mercury are very expensive. I wanted to buy 2 or 3 to leave on the boat just in case.
Sorry, meant to hit reply so you'd get notified! Post is above ...
 

Speedling

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Such a pain that the belt shreds so fast! Do we know why and is there a way to fix it?
 

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Something has to be wrong, my 03 SugarSand uses the same motor and is still running the original belt [ bet I just jinxed that]
 

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Just thinking...is it possible that the voltage regulator is telling the alternator to run at full load, wearing out the belt prematurely?
Another thing to check is the pulley alignment. You mentioned that it was a little offset from the other pulleys. Can you place a straightedge to check in two dimensions?
 
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