New 3D-Printed 944 Timing Belt Tensioner Tool

[RadioRush]

I can see that this is a huge improvement over the twist method. Tom, thanks for your generosity in sharing it!
Has anyone successfully used it on an S2 16V engine without damaging the cam housing? Earlier threads mentioned the weakness of the magnesium post was an issue.

[Tom]

I can see that this is a huge improvement over the twist method. Tom, thanks for your generosity in sharing it!
Has anyone successfully used it on an S2 16V engine without damaging the cam housing? Earlier threads mentioned the weakness of the magnesium post was an issue.

Thank you, and I agree. If you saw my Panorama article on the topic, you'll know I don't believe most people get their belts to factory specs with the 90 degree twist method, and definitely not the first-timers. That said, cars are not generally blowing up from the twist method, but that's almost surely because the belt can be outside the factory's ideal range and do just fine from a practical perspective.

I'd like to hear from anyone who has used this tool on a 16v too. To date, I have not tried it myself on a 16v motor and haven't heard of anyone who has. Time to be a pioneer. There really isn't much pressure put on that post. If it breaks from a plastic tool rotating on it to 7 ft. lbs., then it was just a matter of time. (And better for it to break in the garage than on the highway!)

Someone just emailed me asking about the new and used pointers, but I somehow lost the email. To answer that question, I'd follow the factory recommendations -- i.e., if the belt is brand new, tension it to the N (New belt) spec, which equates to 4.0 on the factory gauge. Once the belt has 1500 miles on it, check the tension and set it to the U (Used belt spec), which equates to 2.7 on the factory gauge. There is no spec for a belt between new and used, but I'd keep it on the N spec until 1,500 and then re-tension to the U spec. Whether you can spin the water pump by hand doesn't factor into the process when using this tool.

[cb_porsche]

Great Idea!

[Paul M]

First drive after new Cam and Balance shaft belts:
My car's the 8V but still thought I'd report back.
First off, a great success owing much to this great little tool.

Upon first installation of the T belt in my little shop, I got things nicely in place with the spark plugs out and a good wrench on the crankshaft. I did about 4 or 5 careful checks regarding cam belt tension.

Firstly, I adjusted it a bit too snug on purpose to stretch things in little. Did a rotation or two and re-check... yep, too tight. Then I eased it off and did the 1.5 tooth reverse method, then set to "new belt" setting. I rotated the whole engine a couple more turns and checked. Reading was a little low but not bad. I snugged it a bit, rotated some more, then sort of "joggled" the crank a little back and forth to do a final check. I set it to be bang on for a new belt and torqued things down.

Now the balance shaft (BSB) was a guess. I set it by hand (of course) guessing about 2.7/4.0 the T-belt tension by comparison... or about 65-70 percent. I guessed around a 135 degree twist on the longest belt run with thumb-finger. Not too tight but no wet noodle either. Torqued stuff and buttoned up the whole job.

Bottom line... complete success! I do have a wee bit of whine at the top end of shifting on a road test. I'd bet I've got the BSB too snug but you have to be a princess to hear the buzz. I'm thinking I'll drive it 500 or so and reevaluate. I'm confident it's good.

Hope this helps others. Sorry about the long winded post.
This tool was a godsend! This site is fantastic.

[Tom]

First drive after new Cam and Balance shaft belts:
My car's the 8V but still thought I'd report back.
First off, a great success owing much to this great little tool.

Upon first installation of the T belt in my little shop, I got things nicely in place with the spark plugs out and a good wrench on the crankshaft. I did about 4 or 5 careful checks regarding cam belt tension.

Firstly, I adjusted it a bit too snug on purpose to stretch things in little. Did a rotation or two and re-check... yep, too tight. Then I eased it off and did the 1.5 tooth reverse method, then set to "new belt" setting. I rotated the whole engine a couple more turns and checked. Reading was a little low but not bad. I snugged it a bit, rotated some more, then sort of "joggled" the crank a little back and forth to do a final check. I set it to be bang on for a new belt and torqued things down.

Now the balance shaft (BSB) was a guess. I set it by hand (of course) guessing about 2.7/4.0 the T-belt tension by comparison... or about 65-70 percent. I guessed around a 135 degree twist on the longest belt run with thumb-finger. Not too tight but no wet noodle either. Torqued stuff and buttoned up the whole job.

Bottom line... complete success! I do have a wee bit of whine at the top end of shifting on a road test. I'd bet I've got the BSB too snug but you have to be a princess to hear the buzz. I'm thinking I'll drive it 500 or so and reevaluate. I'm confident it's good.

Hope this helps others. Sorry about the long winded post.
This tool was a godsend! This site is fantastic.

The balance shaft will whine a little if its near the top (but still within) the factory spec range. It will whine louder and louder as you exceed the spec. So if yours is whining a little, but not whirring like a cheap drone, you are probably around the top of the spec.

[Mother]

Just getting to doing this on my car, and I would love to try this out instead of by hand! First time I have done this job, so it's a little nerve wracking!

[Paul M]

I for one have no problem you messaging me or private message (or whatever) for advice. I'm a journeyman red seal technician but these cars have their own quirks. Just saying I'm no expert but having gone through it once is nice. I'm never shy about learning and then passing it on to others.

[Tom]

Just getting to doing this on my car, and I would love to try this out instead of by hand! First time I have done this job, so it's a little nerve wracking!

Good luck and post any questions you have here. If you are unsure, than many others are too, so asking and getting advice here helps everyone!

[lewiso_944]

Would anyone recommend printing this in PETG? I know it's easier to print then ABS but is it strong enough to work?

[Tom]

Would anyone recommend printing this in PETG? I know it's easier to print then ABS but is it strong enough to work?

No problem. Even PLA is fine. The two areas that see stress are the tab behind the belt and the torque wrench drive socket. The tool is designed with screws to reinforce those areas, making just about any filament just fine.