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Bypass AC compressor 2001 Mitsubishi Eclipse GT 3.0 v6

I charged my AC a few weeks ago. After I added oil it began to make noise. Like metal on metal or a bad bearing. Could be the clutch pulley, bad bearing from what I’ve read. I don’t want to replace it, nor do I want to spend the time and money putting in a bypass pully. I’d like to simply bypass the AC compressor by putting a shorter belt on. Problem is I can’t seem to find any clear info on how and what size belt to use. I see a few saying it can be done and one saying it can’t. Also, is the 2.4 the same as the 3.0 in regards to the belt diagram? Any help would be appreciated, I need to fix this asap, before it seizes up and I lose the belt or damage other stuff. Thanks.

There are kits to eliminate the AC compressor for some engines, but not all.

You may be able to use a shorter belt, but sometimes the shorter belt will contact some part of the front of the engine which would wear it out…or make it impossible to get the new belt on.

You could estimate the length (if it won’t interfere with anything) and if it’s too long take it back until you get the right one.
This may take a few trips to the parts store.

If it is just the clutch…most can be changed out without removing anything but the clutch mechanism on the front of the compressor. But Like the by-pass kit, they are not avasilible for all applications.


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This belt is for the four cylinder PS without AC.

But when it comes to the V6 engine, they all came with AC.

So finding a different belt to eliminate the compressor is going to be difficult.

The belt routing is different between the 4L and V6 engine.


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Is it hard to remove the clutch pulley? Would I need any special tools? Thanks

no, it is not hard to remove the pulley, but you need one special tool to remove some clamps. There are plenty of videos on youtube, some with very good instructions. Like previously said here, make sure a shorter belt does not rub against any parts of the engine or other accessories.

A second option is to completely remove the a/c compressor and replace it with a dummy pulley as shown in the photo. I used this temporarily in place of a broken a/c compressor until I replaced the compresor.

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OP :nor do I want to spend the time or money putting in a bypass pulley.


oops, missed that

If you don’t want to use a bypass pulley, you will need to look at your belt routing and see what happens to the routing if you bypass or remove the a/c compressor. Will the belt hit anything if it went from the pulley directly before to the one directly after and will the tensioner still work?
If there will be interference, a bypass pulley is your only option. If there is room to do it, make a diagram of your new routing and note the position of the tensioner pulley. cut you old belt and use something the same diameter as the tensioner pulley and held in the same place and route you belt around the pulleys to approximate the length.

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So it makes this noise even when the AC isn’t turned on?

why did you add oil? Was this a brand new a/c compressor? I’d be interested to know how you added the oil.

Perhaps OP got his terminology wrong

Perhaps he meant the ac compressor made noise after he added refrigerant . . . ?

Yes. When putting on the AC it gets a little quieter for maybe 10 seconds, then it starts to sound about as loud as it does when it’s not on.

No not a new compressor. I was under the impression that I needed to make sure there was adequate amount of oil because the system was pretty much dry. I was told after that the recharge cans had what’s needed and I didn’t need to add anything special. It was a compressed can version of oil. Maybe 20% -30% refrigerant, but mostly oil. Maybe it was a coincidence, but it got noisy right after that.

I guess I’m gonna have to dig in and see what’s what. I was hoping someone has done it before on this car or a similar model. That way I would know exactly what I need (if it can be done). It’s pretty tight in there and I’ll have to take some stuff off in order to measure, etc…

I’ll look up a video to see what it takes to get the clutch pulley off. If it’s not too bad, I’ll look into getting the part from a yard or parts car (if I can find one)

It looks like I’m gonna have to take some stuff off to measure and size one up, if one can be run without interference.

Once you get the clutch , pulley and coil off, use a string to measure the length of the belt you need. Wrap it around the various pulley you want the belt to turn and cut the string at the appropriate length. Then take it to parts store and compare with the type of belt you need.

Btw, adding only off-the-shelf canned refrigerant should not give you that problem. Does your clutch (not the pulley) even turn when the a/c is on?

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It is uncertain what you are listening to. It is unlikely for a pulley bearing to fail just after recharging the system. You may want to have an experienced person examine the problem or post a video of the compressor malfunction and noise. Many failing compressor vehicles that I have worked on only had contaminated or loose belts.

Good idea, not sure how to post a video tho. And is it possible that it’s not fully disengaging? If so, what would cause that and what would be the cheapest and easiest way to fix that? I’m in a financial hole at the moment, so im unable to bring it in to have a professional evaluate it.

It might be best to start from the beginning and tell us what made you add refrigerant in the first place. Did anything happen during the a/c top off? How did you know that the system was pretty much “dry” (low on pressure?)?
What is happening now when you turn the a/c on? Do you get cold air (besides the noise you are hearing)? have you looked at the front of the pulley? There is a clutch. This clutch should turn with the pulley when the a/c is on and not turn when the a/c is off.

I am still confused when you said you added oil. There shouldn’t be any oil to add. Everything the system needs is what is in the can. Generally, oil is only added to a brand new compressor because they may be shipped with too little or none. If you added oil, how did you add it and how much?

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