Mrmerlin

for any owners wanting to keep the Porsche tensioner ,
I suggest to use Hondabond 4 on the tensioner gasket.
Then use STP oil treatment to fill the tensioner after its installed.
The STP takes longer to leak and the HB4 will help keep the oil from leaking.
Shown here is the visene bottle used to fill the tensioner with the STP.
Also its great for priming the oil pump so you get suction on startup

docmirror

Being certified metrologist, here's the deal with the factory tool. first, it's design is somewhat suspect for measuring belt deflection accurately. You would think the Germans would get their tooling right, but in this case it is somewhat dependent on operator skill, and that should be taken out of the process with a proper tool for the job. I've seen three different people check tension on a belt without it moving and get three pretty different numbers.

Next, since the tool left the factory in the 90s, how many times has it been calibrated to certify accuracy? This is a tool which is not a pass/fail, it has a graduated scale(as does the Kempf tool), with a pointer that has a linear metric behind it. That means calibration, and I'm betting that NONE of them have ever been looked at since the factory.

Added to that, upon manufacture, did the tool maker use a calibrated source with certification to standardize the tools? If they did, congrats, not every mfg is so diligent.

Finally, did that extra small turn on the tensioner fix the light warning problem? If not, there's more than likely a fault in the wiring, or one of the rollers in the system. If yes, that would point to tool use, or accuracy problems, or a fault in the tensioner itself which allows the sensor to stay on for long enough to set the alarm.

Kevin in Atlanta

Any tool that does not provide consistent and repeatable results is not useful. I have used the Porsche tool and it was less than optimal. Kempf's tool is perfect. Consistent and repeatable. The tool of choice for those of us with OCD.

Randy V

To the OP - did you fully rebuild the tensioner each time?

Also, the wire that runs from the tensioner to the ground point often breaks inside the insulation, causing intermittent warnings.

Bjbpe

A lot of very good and useful comments. Thanks all. As for my comment regarding what I believe to be a less than acceptable design, especially for a Porsche, I stick by that. In the aerospace industry I feel that such a configuration would be deemed unacceptable strictly on the basis of reliability. True, a failure of this belt configuration would not leave Messers Aldrin and Armstrong stuck on the moon but it could leave them stuck on the side of the road waiting for triple A with the need for a valve job. While there are undoubtedly timing chain failures, especially in GM el-cheepo engines, I'm closing in on 200,000 miles on my Northstar engine with little likelihood of a problem.

Bjbpe

After my most recent post, I decided to read Randy's comment about rebuilding the tensioner. This I have not done. Anybody want to provide instructions to do that?

depami

I recently bought a Kempf tool so I hope they are accurate enough.

But to say consistency that can’t go wrong, seriously?

Alan

Ahh - yes - thats a pretty important part right there. It is highly likely that the tensioner is dry in which case all bets are off. It won't do any significant adjustment based on temperature. You really need to either rebuild & refill the stock tensioner or get a Porkensioner. There are recent threads about rebuilds.

Alan

Bill Ball

I have one issue with the Kempf tool. I presume it is "calibrated" by Jay initially by adjusting the angle of the tabs to which the spring are attached. Should the tool get knocked around in your toolbox or the spring lose tension, the readings can change over time. I have accumulated 3 Kempf tools, and they each give different readings. I don't think Jay has ever described a specific way to re-calibrate the tool, although I did see a post a while back where someone described attaching a 5 lb weight to the tool which should bring it to the top end of the adjustment window.

docmirror

A 'calibration' is a comparison to a known standard. Hanging a weight off the Kempf tool may, or may not provide accurate results, because this is a direct standards method. A more useful to us method would be to use a newly calibrated 9501 Porsche tool on a car and set the belt to exact tension. Then, that becomes your reference, and the Kempf tool would be tested against the tension on the belt that was just done with the 9501. This is a transfer method, and isn't as accurate.

However, if the tool was calibrated by the weight in the first place, as long as it's consistent, that is what counts. The maker of the tool should provide instructions for continued accuracy, but of course that is rarely done.

Bjbpe

Slowly but surely I am getting an education. What is a Porktensioner??????? Does this have some sort of relationship to Porky Pig?? That was a cartoon character for all you young whelps.

Indeed, if someone has an answer to that minimalist question, I would greatly appreciate any other answer you may have related to "porky" like where to buy, how to install, what classical music to play while installing, etc., etc. Please do not suggest playing any music from the english bugs forward. Ever since 1963 I have smashed all bugs, especially english ones against my windshield.

docmirror

A. Porkentioner is an after-market belt tensioning system. It uses more modern effect.
B. Call Roger at 817-430-2688, he will have that, and the other bits you need(if any for successful install)
C. No relation to Porky Pig.
D. Musical selection while install would be: Pachelbel of course.

newworld

merlin-
i tried using stp as u suggested and ran into an issue. its great stuff, very viscous, but it would not flow into the bleeder valve at all. i ended up putting it in the boot and sealing that end. trying to figure out how to fill the cavity.

i used dwayne's clear pipe plastic method, but it was too viscous. can u show how you filled your tensioner? with visine bottle?

inject it in or bleed?

safulop

Porkensioner is a brilliant invention, so simple. Basically it's a modern hydraulic timing belt tensioner from an Audi A6 or something, modified to bolt into a 928. My old-time 928 mechanics are mystified by it, but they say it is working great. Invented by a guy named Ken who hangs around here much of the time. He also developed a nice drive shaft clamp that appears to prevent the dreaded drivetrain walk forward that eventually leads to thrust bearing failure in the more powerful automatics (anything over 300 hp is vulnerable due to the amount of excess torque).

Bertrand Daoust

Look at the left for "PKT belt tensioner".
Ken as many other great products too.

http://liftbars.com/