I have finally found a problem with my blazer that I can't fix by just reading what has already been posted here. In the last 2 years I have fixed countless problems just by reading what you guys have already written, but now I need to reach out and find some help.

I have a 95 2door 4x4 with the "W" CPI motor, and the other day I started it to warm it up. (I live in South Dakota, and it's been floating around 0 degrees here lately) After idling for about 30 seconds, it started making some really funny noises and running really rough, so I shut it back off. A few minutes later, I tried to start it again and she wouldn't turn over. I could hear the starter engage, and the fuel pump whine a little, but nothing really happened. So, I popped the hood, and got a friend to try to start while I watched to see if there was anything noticeable. I saw a couple of things happen (or more appropriately, not happen). While he was trying to start it, I could obviously see that the serpentine belt was not moving at all. Also when he turned the key, the tensioner and tensioner pulley swung out as though I had a wrench on them to change my belt.

The next day, after getting a ride home from work, I took the serpentine belt off and checked to see if the pulleys all seemed to spin free, and they all seemed to spin with no problems. The alternator seemed to catch just a little, but after I got it to spin a little, it didn't take much effort to keep it going.

After some more googleing with no real results I decided to just try starting it without the belt installed thinking that it would let me know if it was possibly one of the pulleys/accessories that was causing the stop, or something bigger (Like I said before, the temp is floating around 0 here, so I wasn't too worried about the engine overheating in 30 seconds). Lo and behold, she starts.

Does anyone have any ideas on what step I should take next in figuring out what my problem is? Can I assume that it is a pulley or accessory attached to the front of the motor since it starts fine when the belt is off, but doesn't move at all (other than the tensioner going straight) when the belt is on?

Any help or guidance that you can give will be greatly appreciated.

 

Put the belt back on and unplug your A/C compressor... or turn your defrost off.

 

I've had an alternator let go once, seized up with tension on it. Took the serp belt off and it spun fine. Just the bearings let go, also had an a/c compressor sieze up solid one morning. Couldn't get the motor to turn over till I took the belt off. Are you spinning the fan/fan clutch or both the fan and the water pump? Maybe the water pump froze in the cold weather, and you over looked it by just spinning the fan... It has to be one of the accessories. The 4.3 in my opinion is a very reliable engine. Just don't hold It off rev limiter, or burry the rpm needle in the red like li did on accident.. Noo good..

 

@ bandido: I'm guessing that by pulling the plug on the compressor, and turning off the defrost, it will cause the clutch in the compressor to disengage... the pulley spins smooth and free when the motor is off, but the compressor may be siezed up, which would cause it to bind when the clutch is engaged-- Is that where you were going with that?

@ ltx400: I believe that I wasn't just spinning the fan, I was spinning from the drive pulley itself, not the fan blades. Also, if I were to pull my alternator and bring it down to the local parts store to have it tested, would they be able to tell if it had failed as you had described in your post?