2006 Sante ZR6 - is my idler pulley sheered off?

[jkallen21]

First outing this year. Boat began overheating - found the serpentine belt was shredded. I had a spare - went to put it on and it looks to me like the idler is just missing? Love to hear what you guys think and how this might have happened?

[jkallen21]

Update. By some miracle, I had a spare belt and was able to get an idler pulley. I got everything put back together but the engine won’t crank. It just barely tries. Plenty of battery power. Eventually, after about 10 tries, I heard what sounds like the starter motor spinning freely and no longer engaged to turn the engine.
love any insights - I’m mechanical in fixing but I do t know how the whole engine actually works.
thanks

[charlesml3]

Any chance the old belt is all wrapped up around the main pulley and preventing it from turning?

-Charles

[jkallen21]

Well that’s an interesting hypothesis - I didn’t locate all of the old belt beyond a few pieces. I did voluntarily turn off the engine though when it overheated. But the old belt could have been in somewhat of a liquid form and then hardened around the main I suppose. I also didn’t try to restart it until after I got the new belt installed so it’s possible (yet unlikely) that I misrouted the belt.

[jpwhit]

How hot did the engine get?

Don't try to start it with the starter again until you see if you can turn the engine over by hand using a socket on the crankshaft pulley with an 18 - 24" breaker bar. It'll take some force to turn it over by hand, but it shouldn't take all your strength.

If it won't turn over by hand, then there is likely some engine damage from the overheat. If there is damage, if you're lucky it'll be a blown head gasket that has let water or oil leak into a cylinder and it's hydro-locked. If it won't turn, first step is to take out all the plugs and see if it'll turn over by hand then. It should turn over fairly easily with all the plugs out. If water or oil comes out of a spark plug hole, then it was hydro-locked and at least the head gasket on that side is blown.

If it still won't turn over with the plugs out, then get the checkbook out.

In addition to piece of belt wedged somewhere, also look for the remains of the idler pulley. Think either of these blocking the engine from turning is a long shot, but you never know....

[jkallen21]

Thanks for all the ideas. The gauge only goes to 250° and that where it was when the alarm sounded. I killed the engine within 5-7 seconds of the alarm. I’ve got some work to do.

[charlesml3]

Thanks for all the ideas. The gauge only goes to 250° and that where it was when the alarm sounded. I killed the engine within 5-7 seconds of the alarm. I’ve got some work to do.

Given that, I sincerely doubt there's any damage to the engine. It simply overheated and you shut it down before it got really bad.

-Charles

[jkallen21]

A few questions:
1. Above, which direction would the main turn? Clockwise or counter?
2. Is there a problem if it was turned the wrong way?
3. any idea what size bolt is on the main?
I’m gonna tackle this tomorrow so I just wanna make sure

[jkallen21]

Update:
I called PCM And the tech told me which direction to turn the main (clockwise for me but variations of this same engine could be counter). The good news is it turns with moderate effort. There are some parts of the turning that feel like they are being held back by compression because it springs back. However, I am able to get a full rotation without over exerting myself.
The bad news is that I removed spark plug #7 because it was closest to me, and it has a oily/watery liquid on the gap.

I’m trying to get an estimate on a head gasket replacement. The dealers don’t seem to want to do this without having the boat in their hands, and all I’m trying to do is get some sort of estimate on what this costs. Anyone have any idea?

thanks