When to retension ALH TB

[eb2143]

I seem to recall reading a discussion about this topic but I can't find the thread now. I think this may be normal and acceptable. I was doing a routine check of the TB. It had been at least a year since I checked the tension via an inspection mirror.

Would you retension this? (in first half of crosshatching on cold engine--I assume it would move into "proper" tension when the engine was warm"). 50k on belt, installed by me; indicator was in middle of window on cold engine then.

 

[AndyBees]

I've never known of anyone re-tensioning a TB.

 

[red16vdub]

x2 ^^

 

[RIP TDI]

1Z/AHUs had a 30K TB tension adjustment interval (on 60K belt).

 

[eb2143]

I found this article by Litens that discusses the crosshatch area, or belt wear indicator: http://www.litensaftermarket.com/fi...enspanner/VW_1.9L_TDI_installation_notice.pdf

Not very reassuring that this is normal at 1/2 rated service life, but, also found previous discussion on topic and I probably won't do anything, quite yet. One excellent point below is that you need to observe tensioner with engine at TDC or while engine has just started up cold to get accurate idea of tension. Early opinions were to keep the belt tensioned perfectly throughout its service life, later opinions are that it needs to be way out before adjustment is warranted; still other respected opinions take a middle ground. The bentley, with advent of alh "semi-automatic" tensioner, does not address this question head on, but does seem to imply that adjustment should never be needed, as does Litens, IMHO.

http://forums.tdiclub.com/showthread.php?t=65207&highlight=Tensioner+adjustment
http://forums.tdiclub.com/showthread.php?t=181081&highlight=Tensioner+indicator+wear
http://forums.tdiclub.com/showthread.php?t=346069&highlight=Tensioner+adjustment
http://forums.tdiclub.com/showpost.php?p=2367109&postcount=3
http://forums.tdiclub.com/showpost.php?p=1519660&postcount=11
http://forums.tdiclub.com/showpost.php?p=1519419&postcount=10
http://forums.tdiclub.com/showthread.php?t=31587&highlight=Tensioner+adjustment
http://forums.tdiclub.com/showthread.php?t=32193&highlight=Tensioner+adjustment
http://forums.tdiclub.com/showthread.php?t=289501&highlight=Tensioner+adjustment