Jumping belt tensioner - what to check

BuickGirlFromMars

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My main tensioner jumps. when idling, it pops back and forth on the little lines that show you how much tension is on the belt or whatever, and it doesnt seem to occur perfeclty timed when idling, so like not at a certain rotation(unless it moves, idk) but its quite often and gets close tothe last dash mark but will pop back mid way or so.

My question, is this my tensioner?
Is this a drive component?
Easy job? If i am doing it, should I do my waterpump ive been putting off at same time? Maybe PS pump?
Only things that had any cause of concern when putting this belt on last summer:
Idler pulley for SC had noise but no play, that can fail and still function as a car so im gonna send for now.not on main drive either.
AC compressor makes grind spinning, but does function properly and work, doesnt sound terrible running. just spinningturned off and not engaged.
PS Pump had a small amount of play, not concerning enough to replace then and there, but enough you can see very minimal movement while running.
Belt has no cracks, and i used my serp belt tester and it still has proper flex on the belt turned off. not glazed up anywhere that i can note.
 

HotZ28

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Are you sure the harmonic balancer is not failing? Watch it turn with an LED light while the engine is running. It should not have any movement back & forth!
 

BuickGirlFromMars

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im actually NOT confident in that at all because when i did my crank sensor my replacement pulley was junk and i put original back on, it wasnt bad but it wasnt fresh either. ill look at that too
 

JoeBlog

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Not even the same brand, but an 89 Jeep with the 4.0 6-cylinder began eating serpentine belts. I changed the idler, then the tensioner. Nothing worked until someone told me to check the balancer (it was difficult to see directly). Sucker was 3/8” forward from original location. Hope your fix is easier.
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BuickGirlFromMars

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i hope mine wouldnt be.
but my ps pump seems to be the issue, unless its compound. balancer seems normal but the ps pump has got some serious jeep death wobble considering its a fixed pulley

also, you just said balancer on jeep 6 cylinder.

that inline 6 should have much of a dampner other than some tiny weights and a pulley.
 

2007LucerneCXL

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On the PS pulley if someone tried to remove it without a proper puller it can get ugly fast. Again if the PS is bad that's another story, holding a metal flat edge ruler thin side against pulleys is a quick way to check if running true to rest.
 

BuickGirlFromMars

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On the PS pulley if someone tried to remove it without a proper puller it can get ugly fast. Again if the PS is bad that's another story, holding a metal flat edge ruler thin side against pulleys is a quick way to check if running true to rest.
oh no that bitch is wobblin

which compared to 1 year ago is way worse.

its time for a pump, then i will check belt. i will buy a new belt on safe side if my tensioner IS good and this is just from the PS pump, but if tensioner is bad. i should do it when i do that.. hmm,-----------------------------
 

2007LucerneCXL

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As it's maybe something that can be a one project event with the tensioner and PS I guess anything that's attached in the area that hasn't been done would be on the list. As Ron Popeil would say "Set it and forget it" LOL
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HotZ28

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i got water pump, aluminum elbows, alternator(if i wanted, it seems to rwork fine.), idlers, etc
oh no that bitch is wobblin

which compared to 1 year ago is way worse.

its time for a pump,
You think the P/S pump is the problem, but you did not mention a new replacement in the repair/replace agenda?
 

BuickGirlFromMars

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i didnt list it, but it was kinda in the context of "while in replacing PS pump..." that list starts after that

curious, what is the AC component held by the bracket with the low pressure line leading to it? is that a wear-part? Because if its hard to get out with alt on, i could do that too. dont need ac now
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BuickGirlFromMars

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Pump is still bad, PS that is. However, I think I discovered what was causing the problems mostly. The alternator WAS NOT mounted securely, its bolts were worn from play and the bearing had side-load on it and was not aligned perfectly. The balancer also has a lot of visible play when observing, a tiny amount of play when turned off. But once i reseated the alternator tightly and properly positioned(Bolts not tight, backed out, not aligned), it made less noise and my issues lessened and the tensioner jumped less. Still have just about everything on my accessory drive to replace yet, but at least it is improved now?

the only good bearing or pulley is the supercharger.

everything else needs something
 
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