Another Alternator Belt Tensioner - 3VX belts?

[82vdub]

Excellent pics!

[TylerDurden]

3VX 265:

I noticed my tachometer acting erratic after startup (on occasion ), which is my sign that some slipping is occurring. So I gave the belt a tightening at odometer reading 203,960mi.

Installation was at 203,169. = 791mi elapsed.

Maybe it's still breaking-in.

[bbob203]

You have a tac? Man id like if I had one.

[bbob203]

I would hate to have a daily driver that needs the belts retensioned every month.

Tightening belts doesn't take but 5-10 mins though I don't see a big deal.w

[bbob203]

How is the dayci working out tyler?

[TylerDurden]

The belt looks pretty good... it seems to track smoothly, also since it is taller and thinner it has more surface area on the sheave than the shallower Continentals. Only time will tell if it lasts longer than the 10mm wide belts.

I came across some info from the pros:

The Bentley manual has this segment in the maintenance & lubrication section:

Bentley-belt-Info.png

Every four years, lol.

Bando has this in a publication:

Bando-Belt-Info.png

I got belts at my FLAPS @ ~$14, but there is a place online that has the same 3VX belts for ~$8.

[chuckling1]

I recently discovered this thread and decided to give the mod a shot on my 92 jetta 1.6 TD.

I'm into it about 250mi with a gates 7280 and I'm already seeing missing cogs.

I can tell I'm about to become very good at changing these belts. my idler pulley is the original so my next step is to look in to a replacement maybe even a smaller one if that's an option. I read in an earlier post on this thread that belt companies will recommend a minimum wrap pulley so I will be looking into that and maybe that will allow for a smaller belt. Minimum wrap idler pulley with maximum wrap on the alternator pulley minimum tension on the belt.

I'm very interested to see how the belt experiment goes for tyler. I want to know which belt might be my best bet.

All in all I love the dedication of everyone that contributed to this thread. I'm going to try to do my best on reporting as much of my findings as I can. It seems like most of you have more than one car. unfortunately for me this is my everyday car and my drive to work it's 55mi one way so I need at least a semi-permanent solution. Changing belts isn't too bad but it's kind of annoying in December in western PA

[bbob203]

I recently discovered this thread and decided to give the mod a shot on my 92 jetta 1.6 TD.

I'm into it about 250mi with a gates 7280 and I'm already seeing missing cogs.

I can tell I'm about to become very good at changing these belts. my idler pulley is the original so my next step is to look in to a replacement maybe even a smaller one if that's an option. I read in an earlier post on this thread that belt companies will recommend a minimum wrap pulley so I will be looking into that and maybe that will allow for a smaller belt. Minimum wrap idler pulley with maximum wrap on the alternator pulley minimum tension on the belt.

I'm very interested to see how the belt experiment goes for tyler. I want to know which belt might be my best bet.

All in all I love the dedication of everyone that contributed to this thread. I'm going to try to do my best on reporting as much of my findings as I can. It seems like most of you have more than one car. unfortunately for me this is my everyday car and my drive to work it's 55mi one way so I need at least a semi-permanent solution. Changing belts isn't too bad but it's kind of annoying in December in western PA

Where in western pa are you at?

[TylerDurden]

G'day,

There are some tradeoffs when considering fixed-idler pulley diameter: the larger the diameter, the more deflection; the smaller the diameter, the higher the speed/heat.

I originally used cheap bearings from the farm/fleet, which got pretty sloppy in a year. (Unfortunately, I neglected to get a temperature reading before I removed them from service. I was concerned that the bearings were getting hot.)

My guess is the Gates 7280 is identical in profile to the NAPA 7270. The belt is a "nominal" 10mm but the Gates literature also describes it as .41in, which is actually 10.4mm, which is a bit different than the 9.5mm of the original spec for the vehicle.

The NAPA only lasted a few hundred miles for me. Notice how high it rides on the AC sheave - I'm inclined to think the lugs are being yanked right off.

If the vehicles always had this belt issue, the reviews would have been blistering. Assuming the issue is surfacing after ten years, I'd consider what has changed: the pulleys or the belts... my guess is the belts, more than the pulleys. (What belt mfr would want to make a 9.5mm belt just for some old sootbox?)

[chuckling1]

I'm from the Pittsburgh area.

A new 70mm pulley (gates 38088) will be here Monday and I just ordered the bando 2275. It's .38in top width and 27.5 in circumference. I also have two cheapos from advance auto parts that I'm going to wear out as well.

[bbob203]

im think new pulleys all the way around for me. mine are grooved and not perfectfectly mated to vbelts any longer(dished). the idler pulley is damn expensive.

[chuckling1]

just got done putting on a new idler pulley. The one that was on there was so bad that the bearing was clicking and was most likely the original from 92.

240617mi: New Belt, New pulley

We'll see how this goes

[bbob203]

Any idea where new c/s pulley, and waterpump pulley and new a/c clutch pulley.

[TylerDurden]

Not sure on sources for those pulleys.


I tightened up the Dayco today at 204,667mi. (Again, no squeal, but the tach was erratic occasionally on startup.) Last tension was at 203.960, so 707mi.

Not too impressive.

[bbob203]

I pretty much just tension my belts when I think about it.if its dry I might be able to go a week without it. I think new pulleys would do the trick for sure mine are dished pretty good and smooth as mahogany and glazed. I was thinking though if you got rid of a/c you might be able to do a serp belt somehow. I'm pretty sure I saw someone do it with a 16v or and 8v gasser.