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Discussion Starter · #1 · (Edited)
Hey, I’ve started to fix up my old 500sec, and I got it started but belts are overheating and smoking. And I need some help on figuring out what part this is, belt is very tight and gets very hot when running. forums Say that it’s the a/c compressor that is seized but I don’t have a bel connected to it. So if I can get some info on what this thing is and what these belts ar for that would be appreciated
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Usually the AC clutch freezes up and ruins the Belts but it can be any pulley freezing up . Look at the pulleys and see which ones aren’t turning
 

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Discussion Starter · #3 ·
Usually the AC clutch freezes up and ruins the Belts but it can be any pulley freezing up . Look at the pulleys and see which ones aren’t turning
So you’re saying the wheels are frozen and it’s causing it not to turn?
 

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Well, I don’t really know that engine, but it looks like the red circles are around the power steering pump. And it’s pulley.
 

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As Tusabes said, it could be any pulley. What you circled in red is the power steering pump. Did you check/replace that fluid?
 

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Discussion Starter · #7 ·
As Tusabes said, it could be any pulley. What you circled in red is the power steering pump. Did you check/replace that fluid?
Power steering fluid would be in the resovoir up top right, right? And take a look at the new picture I added for a more detailed view.
 

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What’s circled in red in the second picture, that belt looks like it runs the water pump on reading left, the power steering pump on reading right.

In the first picture, the top red circle is around the power steering pump. With the car off, unscrew the black knob. Then you can lift to top/lid and see the fluid inside.

But, again, I don’t really know this engine. Mine just has a single serpentine belt.
 

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Also, if you go back and edit your original posts, we lose context. That can make things difficult.
 

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Take the belt off and try to turn the pulleys by hand. The one that doesn't move, or is difficult to move, is the problem. (The engine pulley will not turn by hand; that is normal.)
 

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Be careful when you tighten belts. They CAN be too tight, in which case they will wear out bearings. And I have found that belts tend to "tighten up" at operating temperature on this all-aluminum engine more than they would on an all cast-iron engine. If the belt is squealing and the belt is reasonably tight, there may be other problems (bearings, glazing of the belt).
 

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Discussion Starter · #15 ·
Be careful when you tighten belts. They CAN be too tight, in which case they will wear out bearings. And I have found that belts tend to "tighten up" at operating temperature on this all-aluminum engine more than they would on an all cast-iron engine. If the belt is squealing and the belt is reasonably tight, there may be other problems (bearings, glazing of the belt).
The belts are very tight and whenever I step on the gas is squeals and smokes a lot
 

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For Best diagnosis, remove and label all your belts and check your pulleys. The ones circled on the right side in your photo is the power steering pump, this should turn freely by hand, Your alternator belt should also turn freely by hand also your water pump. While spinning the various pulleys make sure you don't hear a grinding noise a sign of failing bearings. The lowest pulley also known as your crank pulley located in the middle will not turn as that is connected to the crank shaft of the engine and this is the one that gets all of them going.
 

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If the belts are tight then one of the accessories must be seized. It wasn't clear: do you see one that isn't turning when the engne runs?
 

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Discussion Starter · #18 ·
For Best diagnosis, remove and label all your belts and check your pulleys. The ones circled on the right side in your photo is the power steering pump, this should turn freely by hand, Your alternator belt should also turn freely by hand also your water pump. While spinning the various pulleys make sure you don't hear a grinding noise a sign of failing bearings. The lowest pulley also known as your crank pulley located in the middle will not turn as that is connected to the crank shaft of the engine and this is the one that gets all of them going.
Okay, thanks for the info. Does it matter the orientation that the belt goes at on the wheels? I’ve never done belts before but I know timing needs to be perfect.
 

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Okay, thanks for the info. Does it matter the orientation that the belt goes at on the wheels? I’ve never done belts before but I know timing be perfect.
On used belts try to keep the orientation the same, on new belts it does not matter. As mentioned above all of the other pulleys Power steering, Water pump, Alternator and AC are referred to as accessories driven by belts off of the crank pulley.
 

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Discussion Starter · #20 ·
On used belts try to keep the orientation the same, on new belts it does not matter. As mentioned above all of the other pulleys Power steering, Water pump, Alternator and AC are referred to as accessories driven by belts off of the crank pulley.
Thank you!
 
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