N8Custer

I have a 2003 C230 Coupe. When I was driving the other day, I heard loud belt noises and pulled over to inspect. My serpentine belt had a bunch of slack and the tensioner pulley was completely gone. The new pulley that I received came attached to the tensioner bracket. In order to remove tensioner, I have to take off supercharger and intake manifold. Would like to just change the pulley (car is stranded in advance auto parking lot and weather is horrible) Can I just remove the pulley from the bracket using T50 tamper resistant Torx? Is there anything specifically that I can do to test the tensioner that is already on car? I don't want to change only the pulley then have it fail because of the tensioner. I guess I could just change the pulley to get car home, then change tensioner bracket later. I am also changing the roller pulley and serpentine belt. Is there any certain tools I should have to make this job easier? Would appreciate any feedback.

Thanks

Pulley Gone


What was left of Pulley


New Pulley

xpoloniusreapx

I had to do the same on my 03 coupe just about 2 weeks ago. I replaced just the pulley. When I was routing the belt, the amount of pulling I had to do on the tensioner to get enough slack was enough proof to me that the tensioner was still alright. It is much easier if you remove the supercharger silencer to get to the pulley.

N8Custer

I changed pulley today. Bearings were shot in pulley but tensioner was good to go. I also removed silencer to have better access. Thanks

hiralah

Did all this but can't release the tension on the belt to re-install new one - PLEASE TELL ME HOW........

Benzoman5000

All you have to do is use a t60 torx socket bit which is right to the left of the pulley and turn it counterclockwise and it will release the tension on the belt. My only question though is how to tighten the serpentine belt. Anyways, good luck!

pcy

The only function of the belt tensioner is to keep the belt tight.

Benzoman5000

So is there any possible way that I stretched the serpentine belt? I have 1-1/2 inches of space on the belt from the power steering pulley and it will not get tight, but the tensioner is still hard to pull back and seems to work.

pcy

If you've routed the belt via all the pullies (idler pulley, tensioner pulley, PS pump pulley, AC compressor pulley, crankshaft pulley, and alternator) and the tensioner is engaged on the belt, there should be no slack on the belt. I have not seen belt being stretched that much; although it's possible.

If you are sure the belt is routed on all pullies properly and there is slack, then only thing you can do is order a new belt.

ontmiss

If you've routed the belt via all the pullies corectly as "pcy" says then the only thing could be a tensioner. Doesn't metter that the tensioner is still hard to pull back, could be that doesn't go all way back as happened to me. Like when you release it, it goes back only half way or so, like 40° of 60°

Benzoman5000

It's actually rubbing up again the torx bolt, so could that be going back too far?

pcy

can you take a picture of the tensioner with belt installed and post it here?

When the new tensioner is shipped, they usually put a pin in the tensioner so that the pulley doesn't cover the mounting bolt hole. After installing the mounting bolts for the tensioner, you need to remove that pin. I am thinking that you may not have removed that pin; as a result, the tensioner is not releasing fully. Arrow in the below picture is what I am talking about...

Benzoman5000

I only changed the alternator. Nothing else has been modified or changed. After installing the alternator, I tried to start the car and it wouldn't turn over. I took the battery to Autozone to get it recharged and still no turn over of the engine. Sounded like the belt was too tight. Indeed it was, so I yanked on the crankshaft pulley until the belt loosened up. It became too loose. I'm thinking I ruined the tensioner or crankshaft or somehow stretched the belt in the process.

ontmiss

You can always buy onother belt compare with yours, and if it's same you can return it to store.

pcy

^ +1.
Compare the belt's length to a new belt. If the belt length is the same, then looks like you may have damaged the tensioner. I don't understand how you could've damaged the tensioner by hand.

ontmiss

Here some pics if that can help you somehow.

Benzoman5000

Thank you so much for the pics!! I did have it on wrong this last time, but I did put it back on the right way once again and it still will not start. Is the crankshaft pulley suppose to be in a certain position for the engine to start? As I noticed it is marked with numbers on the outside of the pulley and I have turned it many times and it is not in the same place that it was when I took the alternator out.

pcy

Crankshaft pulley doesn't have to be at a specific location with respect to the other pullies and the belt. Only crankshaft pulley needs to be at a specific location w.r.t the internals of the engine. If you didn't remove/install the crankshaft pulley, then you don't need to worry about that.

You say that you've now put the belt correctly and the car doesn't start. So, the belt is on all pullies and it is rotating properly, right?

After you installed the alternator, did you connect the alternator wires correctly? Are the battery cables connected correctly? While removing the alternator, did you remove any of the ground connections?

Benzoman5000

I hooked the alternator up correctly. And the ground from the battery is the only one I took off I believe. Although I bought the alt on ebay and no one in town could test it, so I don't know if it's good or not. The engine would still start though correct?

pcy

If the battery is good (above 12V) and all the electrical connections are intact, and you have not touched anything else, the car should start right up. The engine worked fine before the alternator replacement, right?

Air, Fuel, Spark - what is missing?

Benzoman5000

The engine ran just fine before the alternator replacement. The battery is great. The only other thing I've done by accident was drain reserve water and the power steering fluid drained out, but that wouldn't cause the engine not to start I don't think

Benzoman5000

I have right now the silencer off and air box. Because I ruined the airbox while taking it off. It just sounds like the belt is too tight. It tries to turn over but doesn't. I'm thinking maybe the starter went bad also maybe. At this point though I have no idea. The car started and ran fine before. Then the battery kept going dead. I figured it was the alternator because I bought a new battery. I'm in the dark now on the whole car.

Benzoman5000

air intake not air box

C230 Sport Coup

You may have a combination of issues.
Do you have electric seats?
Perhaps you have the dreaded seat module issue, makes the battery dead overnight.
You can solve that temporarily by unplugging the modules under the seat.

What about Fuses? Have you checked those?

Have someone crank the ignition and see what the voltage is at the time it is cranking.
Should still be 11-12v.
The car would run without the belt entirely.
Remove it and see if it starts just momentarily.
Remove and see if any pullies are stuck.

And as you said EBay alternator.
Is there no auto electric shop in town?
Get it tested, and or get the old one repaired.
I hate buying rebuilt crap.
Better to have the original alternator rebuilt by a local man.
It helps if you put your location in your profile, so people can know
if you're in the US, or what. It effects the answers you'll get.

As far as pulley routing, please refer to your owners manual for the correct routing.

pcy

That's a good suggestion. If the car starts with the belt off, then one of the pullies is stuck. Then the diagnosis becomes much easier.

Benzoman5000

earlier I took the belt off and tried to turn the alt. pulley to the right and it was seized up. I took it off and it was fine. I realized I had tightened the bolts a little bit too tight. Whoops. Now it's working, but making a loud noise. I'll have to deal with it for now and probably just buy a refurb alt from autozone. That's what I get for buying used off ebay. Thanks for all the help guys!!