Serpentine Belt

[RednBlack]

Anyone ever have the tensioner go out of alignment? Bearing is perfect, back stud locks like it should, but the case is spreading apart on the tension side. Bolt is not bent. Everything looks great, except the belt crawls off about a 1/4 ". Not good at 7000 RPM. (or thereabouts)

[WhiteZ34]

I had one go bad about a year ago. Luckily I was out of town and left it at my parents house. My father decided to go for a drive and it went out on him. So he payed to have it fixed. I would give ou some advice if I knew what the actual problem was.

[BMFH]

Hello All

The problem with the tensioner is common to ALL types of belt tensioners.

That is except the ones that have sholders on the edge of the pulley, (sholders can and will be worn off if the belt runs against them for an extended period of time).

Groved type pulleys for the surpentine belt to run in will keep the belt tracked no mater what, barring a complete failure of components.

During their normal lifespan they are always moving back and forth, if only slightly, they have a plastic wear surface installled internally (I.E. Plastic Bushing) to keep the metal parts seperated, provide a wear / bearing surface, and keep the parts properly aligned with each other, as it wears the pulley is pulled to the side by the belt tension and allows the arm to move out of alignment, this forces the belt to walk / track off the center or the idler roller.

Observe the belt and tensioner operations while SOMEONE ELSE THROTLLES THE ENGINE, STAY OUT OF THE BELTS EXTENDED PATH WHILE OBSERVING THE MOVEMENT OF THE TENSIONER AND BELT, SURPENTINE BELTS HAVE BEEN KNOWN TO CAUSE SERIOUS INJURIES IN THE PAST, IF THE BELT HAPPENS TO ACCICENTLY BREAK WHILE REVVING THE ENGINE,

"NEVER EVER" LAY OVER THE TOP OF THE BELTS OR FAN AREA WHILE REVVING ANY ENGINE, PEOPLE HAVE BEEN "KILLED" BY FAN BLADES GOING THROUGH THEM, I KNOW WE DON'T HAVE A FAN THREAT, BUT JUST IN CASE! REMEMBER MURPHY'S LAW.

Some idler rollers have a slight crown to the belt contact surface, this crown helps keep the belt tracked in the center of the idler roller, but this crowning is not designed to compensate for any gross miss-alignment of the Tensioner Arm or pulley.

If any of you have ever had any experance tracking a conveyer belt by miss-anligning the rollers at each end or the conveyer belt it will help you to understand the way the belt can walk off the tensioner pulley.

Install a new tensioner assembly and everything should go back to normal, that is if everything else in the path of the belt is in correct alignment.

Make sure all Accessory components have all their bolts installed, are tight and secured proplerly so as to NOT effect the designed in belt alignment by the OEM.

Hope this Helps

John

[RednBlack]

After taking it to work and looking at it under the comparator, the inside of the spring housing has cracked and is causing the "out of alignment" issue. I always get the "Wierd Shit". Door noises, full blown cat destruction, tires losing air, etc. It's that damn black cloud.

[napatiger]

same exact thing happened to me.

but the tensioner actually separated when I dissasembled the engine.

anyways I had bought a new one and noticed that my old one looks just like that; although I didn't have a problem with the belt prior to engine removal.

maybe if the mounting bolt loosens on the older units they release tension in the spring and break the seal.

[RednBlack]

This sucks! New tensioner, new belt...WTF? Could the UD pulley be tapered that much? Note the belt crawling off 1/4"? Added Note: It has never thrown a belt. (Not at my house anyway. :P ) And I race the puppy!

[your_I.D.]

Are you sure the little timing tit on back of tensioner went in the hole? How long have you been running UD pulley?

[RednBlack]

Tit is in the hole. (That's funny) UD pulley has been on about a year. Not sure if the previous owner had the same problem. I'll pull the whole mess tomorrow and indicate it all.