The cam and balance shaft belts are a part of the 944 Porsches that require an unusual amount of maintenance. When a cam belt fails, the relative position of the valves-to-pistons is disturbed and invariably one or more pistons strike a valve. This results in bent valves and an expensive repair.  All 944 owners should have some appreciation for belt maintenance. 

For some reason there are a high number of belt failures on these engines. There are all sorts of theories but I'm not sure any of us really know the answer. I've managed to avoid belt problems,  maybe I've been lucky. I keep up on my belt maintenance and I try to get a good look at the various belt components. I look for wear, feel the rollers for smooth operation or significant amounts of belt dust or engine oil and inspect the covers for signs of rubbing. I also like to get a look at the belts with the engine running. If in doubt, I replace suspect components.

I'm just learning about the auto-tensioner that began showing up on 87 and later engines.  Auto-tensioner is an unofficial name and a bit of a misnomer. There really isn't vry much automatic about it. It is simply a spring loaded device. When the positioning bolt is loosened, the spring places approximately the right pressure to tension the belt. With this setup, one could, theoretically retension by simply loosening the positioning belt and the re-tightening it. 

The down side is that this device is bulky and really crowds an already congested area on the front of the engine. If you use the Krikit to tension your belts then you will find that the auto-tensioner gets in the way and makes getting a good reading of the balance belt difficult.

The pin wrench can be used to maneuver the auto-tensioner. I have been ignorantly unaware of this for many years and as a result my pin wrenches have been made in such a way that they could not be used for this. Realizing my error, I have redesigned my pin wrench to accommodate the auto-tensioner. I should also point out that  two small bolts and any sort of lever placed between them will work almost as well. At any rate, some form of rotating the auto-tensioner against it's spring is needed to get it to a retracted position. Once there simply tighten the positioning bolt  to hold it there temporarily. It must be retracted to install or remove a cam belt.

A couple of things to note in this photo: the lower belt cover is installed, it must be loosened in order to get the pin wrench into position. Also note how this particular pin wrench is bare steel, this is because this is a test fit of one of my old-style wrenches. All of my pin wrenches now have a black oxide finish.

Installing the cam belt is easy, just be sure the cam and crank are both at TDC and the auto-tensioner is retracted. Then put the belt on the crank and through the auto-tensioner. The auto-tensioner will have be almost completely removed to allow the belt to be fed in behind the auto-tensioner's roller. Once the belt is in place just loosen the positioning bolt and the auto-tensioner will snap into place, applying tension to the cam belt. Secure the bolts and the cam belt is ready for a running inspection. When it comes time to re-tension, just loosen the positioning bolt briefly and re-tighten it. That's it. 

Well now wait just a sec there Bub. A lot of guys do it that way and I've gotten away with doing that too. But, for the record, these auto-tensioners are well known to NOT put sufficient tension on the cam belt. Its probably a good idea to check the tension.

Here is a link to more info on the balance shaft alignment.