P9201 tool theory of operation

[Steiner944]

AFJuvat - thank you sooooo much for that walk through.

Porsche-O-Phile - great point, exactly what I was doing and getting variable readings. I will purchase the calibration bar. One would think it is ready out of the box, but who knows.

I will continue to play, until I get comfortable. Heck, it has sat for three months another few days isn't going to kill me.

Frank

[ae1969]

I was getting whacky readings at first. It takes a few tries to get it consistent.

The trick is to make sure

1. Dont twist the body of the tool
2. The rollers are precisely in the gap

I tend to just wiggle the tool as I push down to lock the pin. I get very little variation now.

P.S when the engine is warm those belts ride up to 7-9 on the guage. AND ITS SNUG.

[Razorback1980]

Thanks for starting this thread Frank....a lot of good information in here. Thanks to all who have contributed and shared. I keep copies of threads I find helpful offline....this one just moved to the top. Thanks again everyone.

[yellowline]

Oh, one more tip...park it where you want to check the tension. Let it sit overnight. You want the car stone cold when adjusting the tension.

[Steiner944]

All,

thank you for this valuable, valuable information. There is definitely a technique to using this tool. What you have done here is way above and beyond Clark's garage. You have created the Masters level course..........Belt Tensioning 601.


Cheers

Frank

[hughett]

The 9201 tool is very tricky to use and takes practice to get repeatable and accurate readings. I find that getting a good reading on the 968 is more difficult than on the 928. The least jiggle can upset the reading.

Harvey

[swimmingly]

AFJuvat,
Thanks for the write up about calibration and operation of the tool. I ended up doing everything like you said and you won't believe what sort of tension numbers I was running.

As SoCal stated in a previous post of mine, I had a fair bit of belt whine.

Honestly, for anyone who thought 5.0 was bad, wait until you hear what my belts were at...

Okay, now that I've built up enough suspense. I put the tool to my belts and got readings of around 8.0 on both my timing and balance belts!!! Ran like that for about 2k miles now. I'm in the process of refreshing my engine bay and boy am I glad that I checked the tension. Hopefully my rollers (all roll freely without any noise) and water pump (once again, tried to wiggle and there was no noticeable play) haven't been damaged.

Thanks again guys!

[Slam]

Hmmm...

Spare head - $100 or so
Gasket set - $100 or so
Krikit tool - $15.00 or so
Fluids, fasteners, odds and ends - $35 or so
Various special tools - depends who your friends are
Learning to change your own head - priceless.

Although for some a dangerous way to live...


Porsche special tool 90210 (that's a joke, by the way) $450 or so
Belts - $100 roughly

Not as steep a learning curve as a) above


Hiring a shop to do this for you - $500 to 1,000 (it seems) or so



All depends on what floats your boat.

Good thread. Wonder if we'll hear from ccypher about the twist...

I'm still dying to know how the krikit specs out against 90210. I'm a krikit-and-change-belts-every-two-years guy, myself.

With a spare head...

[WolfeMacleod]

[QUOTE]Originally posted by AFJuvat
[B]. If you have the updated waterpump with the guide bar, you need to remove the bar to measure the tension accurately.[/quote

What I'd like to know is: What about those of us with a spring tensioner? I was told by the deler that with those, there's no need to use the 9201 tool...just release the tensioner, and you're set. However, someone else says use the tool in conjunction withthe spring tensioner...which I believe in.
But, withthe spring tensionr, you can't remove the guide bar, as part of it fits behind the tensioner. Or...can you??

[hughett]

Good question...I'd like to know the answer too.

Harvey

[AFJuvat]

As I had stated in my original post, you DO NOT need the tool for the cam belt if you have the spring tensioner. you loosen the two nuts on the tensioner and let the tensioner deflect as much as it wants too. FWIW, if you measure the belt tension on a new belt with the auto tensioner, it will notmally read 5.0 - 7.0

You must still stick to the retension at 1K miles, check tension at 15K miles, and replace at 3 years or 30K miles, which ever comes first.

You still need the 9201 for the balance shaft belt, regardless of what year you have. This is also applicable for 924, any 944 and any 968.

AFJ

[shikzachaser]

I am by no means an expert so please don't place me in the league of SoCal et all, I am still way down the foodchain compared to most of the guys. I use my next door neighbor and his tools. He has been a Porsche dealer mechanic for 25+ years. I am learning by filling him with beer and attempting to do things myself under alcohol shaded influence. Basicly it goes something like "not that way ahole, like this" now you try. Next time I will know. I am a mechanical engineer by training but I learn more from people that do things than I ever will learn by reading. I also finally realized the tool is not a measure of any real unit. I am not too bright, when I started the supercharger idea for my car it took me a month to figure out where 2 extra injectors would go in a 4 cylinder engine.

Steve

"Normal people feel that if it ain't broke don't fix it. Engineers feel that if it ain't broke it ain't got enough features yet."