Belt tension question...

[Poorboy]

Changing out the Water pump in The Little Red Wagon ('96) and want to know how tight the belt should be. Everywhere I look I get the same Basic thing "using a Tension gauge"...

I don't have a tension gauge, so I have to do this old school.

I'm reusing the old belt BTW.

Engine is the 4-oh with A/C.

[cpttuna]

Tight. I bought a new Gates belt for my wife's 01. Belt squealed for a month(no matter how tight I made it). I went to Autozone and bought theirs and not a peep out of the belt.

[Poorboy]

That's what I figured. Güdentight would be the answer then.

[Firemanray]

Excellent question. I don't know the "technical" answer but I tighten mine until it quits squealing under a load (A/C, power steering etc.)

[Tobyspaw]

I do what fireman ray does...exactly.

[Cheromaniac]

If the belt has more than a 1/2" of deflection or you can manually twist it more than 90 degrees along its longest free length, it's not tight enough.
OTOH you won't want to overtighten the belt either 'cause that'll place extra load on the alternator pulley and idler pulley bearings accelerating their wear.

[Poorboy]

If the belt has more than a 1/2" of deflection or you can manually twist it more than 90 degrees along its longest free length, it's not tight enough.
OTOH you won't want to overtighten the belt either 'cause that'll place extra load on the alternator pulley and idler pulley bearings accelerating their wear.

Kewlies! Thank you!

It was fairly tight before, but I think with the craptastic Water pump, it wouldn't stay tight.

It all goes back together in the morning. Now that I have a T-stat with a bleeder pin, it shouldn't be a huge pain to bleed the system.

I'll let y'all know once it's up and running.

[XJ Wheeler]

That's what I would say... I always tighten it till I can't twist it more than 90*.

[Poorboy]

That's what I would say... I always tighten it till I can't twist it more than 90*.

I couldn't twist it more than about 20 degrees before the pump died. It was really flappy with the bad pump.

We'll see how the thing does tomorrow. I got lucky, the idler (fan pulley) and tensioner are in great shape. No noise, no excess resistance. The Alternator seems good to. A/C clutch.... has a teeny bit of play, but I'll let that slide.

[4.3LXJ]

My rule of thumb is to find a nice long stretch and push on it. It should deflect with about 20 lbs of pressure and then stop after about a half inch. That is the best way I can explain it

[Poorboy]

Now, does anybody know the toque specs for the water pump to block, t-stat housing to head, ps pump to wp, ps to manifold and bracket to block? The numbers I have seem way, way high for the size of bolts...

[4.3LXJ]

This is for a TJ, but it will work

[Poorboy]

Those seem like far more reasonable numbers than what I found. What I really need is an FSM for the XJ platform....

[4.3LXJ]

That was from my FSM for a 98 TJ

[Poorboy]

Not much, if any differences in bolt torque between models with the same engine. Thank you good sir, I can now go put the little red wagon back together.

[prcjeep]

The nice long stretch of belt, is likely the length running between the alternator and the a/c, this is where you would want to push on it to gauge if it moves more than a half inch. On my XJ its tought to get an arm in there to push on the belt due to the battery location.

[Poorboy]

I got it güdentight. 1/4" of movement. No slip, and no squawk. Best of all, no more rattle from the pump.

[Poorboy]

I put a couple hundred miles on it in the last couple days. Belt needs to be tightened again. It's not bad, just squawks when the a/c first kicks on. After that, it seems fine.

[4.3LXJ]

Serpentine belts do stretch right after you put them on. They say they are not supposed to, but they do a little

[Poorboy]

Any new belt will stretch. This belt isn't new, but not old either. You can still clearly read the lettering on it.