Causes of Balance Shaft Belt wear?

[Devilsfutbol17]

I was just replacing my timing belt due to it having some damage. I found the culprit of the timing belt damage and will easily take care of it. But while I was down there, I noticed my balance shaft belt has wear on the wheel or drivers side of the belt.

It does look a little loose as shown in the video, could that cause the wear? I won't be pulling the BS belt until next weekend, so any help is appreciated.

[YouTube]B7U7nva3uXM[/youtube]

 

[bmoha7321]

Or balance shaft belt? It'd be hard to feel bad bs bearing by hand. Unless its destroyed. You could spin the bs tensioner pulley and see what it feels like. Theres no way given your circumstance that I'd try to reuse the front bs without looking at the bearings. Why chance it? Just eliminate it and the rear one. It sucks but I'm sure the last time was expensive.

 

[HaveBlue83]

the BS pulley is OEM mitsu new. its fine. I would LOVE to do a BSEK but to pull an engine that has 161K on it and do all that work that is gonna disturb the front cover stuff, I'd rather just drop in a 6-bolt or new 7 bolt.

just sayin it blows. yeah it cost me about $400 to redo it, with a head in not as good of shape.

if the belt was new kevlar, and the tensioner pulley was OEM new, then the bearings are the only other wear area I can think of....unless it wasn't tensioned properly...but I would think the edge would show wear from that.

 

[DSM1G90]

..I've always wonder on them Kelvar belts since they seem not to have the reliability as stock Mitsu or even Contitech belts ( which Contitech makes the belts for Mitsu in the first place..) They may be good for the drag and track where one would be pulling them out on a frequent basis, but for duration, I would remain with stock high nitrile belts.

I'm just running stock Mitsu belts and after 24K miles from the install, no probs ... - DSM

EDIT: I did like that report within that link above, but wonder on a small goof in the BS description of both BS shafts counter rotating. The rear shaft is rotating CCW where the front is rotating CW. That's why you do either the screwdriver in the hole trick to get the rear BS in phase, or the trick mentioned in VFAQ which is tons easier-by rolling the oil sprocket to where it rolls CCW to signify that the BS is in phase.

But, he's right about Suba's boxer 4 motors ... with pistons are 180* apart, they do cancel each other out and run smoothly.
Just that they need to get the plug fouling situation cleared up and move the turbo away from the block on the STi's so the heat of the turbo doesn't cook up that part of the block.

Kinda funny hearing Sti's, chugging away on 3 cylinders since the one got a bit overcooked and scorched the cylinder walls, thus loss of compression a bit..

Course, Subaru's background was in avation why they took the aircraft motor for automobile use.

Even the VW's flat four is the same, but the connecting rods are joined together-end to end-around the one lobe.

But, who asked me .. I'm still stock as it came out of the factory, but just got a JDM VR4 and a b16g ...

DSM

 

[TunaTalon]

I did like that report within that link above, but wonder on a small goof in the BS description of both BS shafts counter rotating. The rear shaft is rotating CCW where the front is rotating CW.

Yes, one shaft runs CW and one CCW, that is the definition of counter-rotating, so where’s the goof?

 

[DSM1G90]

Unless he means that the two shafts spin-each in different directions, but it was worded it as if they both spun CCW and I took it that way...

 

[TunaTalon]

He = me. If the document is worded ambiguously I can change it. I just checked the description of the balance shafts and found:

There are two eccentric
shafts counter-rotating at two times the
engine speed and registered so that both
shafts "up" and "down" forces are
additive to counter the up and down forces
of the piston imbalance. Since the two
shafts counter-rotate, the left to right
forces of the two shafts are balanced to
zero.

That was my best effort to make it clear along with Figure 34. It still seems clear to me. Thank you for making the effort to dig into the physics instead of just accepting the lore on the topic.

 

[DSM1G90]

Sorry on that-didn't know it was your page..no offense, of course.

I have a habit of digging into the finess of things..including the physical logic in which I then pick apart to get details so I can understand them.

Simply put: I was looking for CW and CCW descriptions and missed it since it was hidden in a compound word that I wouldn't have used.

thx-DSM

 

[kablamo97spyder]

just 86 that s**t already!!!!