View Full Version : Engine belt won't go back on??? HELP!!!

05-01-2012, 05:59 PM
My engine's serpentine belt will not go back on. In the fall of last year I had to remove my alternator and mounting bracket for a broken bolt. I reinstalled the alternator's mounting bracket onto the engine exact where it was removed. The alternator was reinstalled onto the mounting bracket. Now, the belt won't go back on. The belt tensioner/adjustor appears to be retracting just fine. Could it not be opening fully making it impossible to reinstall the belt.

How much should the tensioner move?

This is on a 2002 L-18 engine?

05-01-2012, 06:43 PM
Try reversing the process. If you started at the crank say and then wrapped start at the alternator ect.

05-01-2012, 10:38 PM
Try using a cheater bar on whatever you're using to take the tension off of the tensioner. I had a similar problem and found that the tensioner would move a lot farther than I was moving it without the leverage.
Once I figured that out..... it was a 10 minute job!

05-02-2012, 01:59 PM
start putting it on from the left side, pull the lanyard and turn the key once or twice, the engine will turn over and belt should slip right on perfectly

05-07-2012, 03:54 PM
Ok, i've tried EVERYTHING. This damn belt just will not go on. I've narrrowed it down to 3 possible problems.

1) The belt tensioner is not collapsing all the way. This seems hard to believe since the tensioner does rotate about 160 degrees. Do anyone know how much the tensioner should rotate (in degrees)?

2) Alternator / Alternator bracket is installed in correctly. This seems virtually impossible since there are only 3 bolts holding the bracket to the engine block and they all line up exact. Also, there is only one way the alternator can go on.

3) Belt is too short. This also seems completely unlikely since it's the belt that has been on the boat since I got it 7 years ago and I've had the alternator and belt off at least a dozen times. Does anyone know the correct serpentine belt part number for a 2002 L-18 (496) engine?


05-07-2012, 04:06 PM
are the belts the same size? did you try what johny123 suggested?

05-07-2012, 04:09 PM
I have not changed the belt. During the winter I removed the alternator to fix a broken alternator bolt. To do this, I had to remove the alternator mounting bracket (held to the block by 3 bolts). Once the bracket was fixed (broken bolt drilled out), I reinstalled the alternator bracket onto the block and reinstalled the alternator. Now the existing belt does not fit. I'm leaning to replacing the belt tensioner - thinking it is just not rotating enough to allow me to get the belt back on.

05-07-2012, 04:13 PM
Odds are the alternator bracket is not installed properly.

05-07-2012, 04:15 PM
That's exactly what I was thinking so I took the alternator and bracket off again and verified the installation. There are onlyh 3 holes in the block that line up with bracket so I'm pretty sure it's installed correctly. I'm going down to the boat again this week and taking the alternator and bracket off once again to triple check the install.

05-07-2012, 04:26 PM
When things don't work out for me on reassembly, I usually ask myself "what stupid thing did I do?" I once took my snowmobile's suspension apart at the end of the sled season and didn't get back to working on it till December. First and second attempts at reassembly turned up too many spare parts. Third time was a charm.

05-07-2012, 04:31 PM
I'm hoping your right on the 3 times a charm. This is just too easy to not go back together. I've had this alternator off many times and it always goes back together without any issues. I'll let you know. I'm sure it is something really stupid I'm forgetting.

05-07-2012, 04:33 PM
Good luck.

05-07-2012, 05:09 PM
I really hate to ask (honestly) but are you certain that you are installing it correctly (correct path). Sorry, not much else I can think of since it is the belt that you took off.

Good luck!

05-07-2012, 05:11 PM
I really hate to ask (honestly) but are you certain that you are installing it correctly (correct path). Sorry, not much else I can think of since it is the belt that you took off.

Good luck!

76S&S - Another great question. I went to my dealer and took a picture of the correct belt path. There really is only one way this belt goes back on. I'm pretty sure I have the path correct.