crooster

I haven't seen too much feedback posted on Bruce Arnn's 920x tool, so I thought I would give my impressions. Note that this was my first time tensioning belts on a 944 so I haven't used the Kriket or the Porsche 9201 tool.

The construction, as with Bruce's other tools was top notch. I had previously used his rear bearing tool that greatly eased removing and inserting the bearing into the hub. So I ordered the full Max kit that includes the usual wrenches, flywheel lock and the 920x tool. It wasn't cheap but I hope to be tinkering on these cars for some time to come.

The instructions that Bruce provided were quite easy to follow and I felt fairly confident working thru them. I found that the 920x tool provided very consistant reading - when you snap the tool, the variances of measurement were quite small. The tools comes with fittings to tension both timing and balance belt. You have to switch over the "foot" of the gauge from a roller to a block to measure balance belt tension.

So although my experience is limited I would recommend this tool to anyone who is a bit leery of the Krikit and its reputation that its difficult to get repeatable readings.

EMBPilot

what he said. +1

FRporscheman

Thanks for the review. I might order one next time I need to do a belt job.

KY944S

I have the complete kit. It has my vote

Yummybud924

I did not have any luck using this tool. When I followed the instructions, i would get a really loose belt when it was supposedly at the correct tension. I could feel that it was way loose (the belt would slip if i ran the engine).

so I'm not sure what went wrong when I used it. I checked it a million times and still got the same results.

KY944S

^^^^---You should have contacted Bruce

crooster

On the cambelt did you tension the long run of the belt first? With the flywheel lock in, or parking brake set, rotate the cam gear CCW with a fair amount of force to get the slack on the lower run of the belt.

Techno Duck

Another happy user of the 920x here. In my opinion easier to use than the 920x!

Trucho-951

Just out of curiosity what type of variability did you get with this tool on the cam belt?

I used it last month and found it a little tricky to use, especially trying to keep the nylon roller perpendicular to the belt when using the metal reference bar.

crooster

The worst I got about 1 to 2 of the smallest graticules on the indicator dial, so about 0.002. I didn't have a problem keeping the roller at right angles to the belt.

Mighty Shilling

it's frickin great! easy to use, accurate, can't go wrong.

And I've got a friend who's a programmer making a program where you type in the ref bar reading, and it'll spit up the ideal, min, and max tensions... I know the math isn't hard, but I want it to be retarded easy...

schwank

I was a total noob... went through the instructions provided to retension my belts after WP replacement.

No problems, everything turned out just fine. I set it by the 920x, and afterward the finger test was just about right.

Bruce's tools are worth every penny in my book... the offset tensioner wrench rules too!

Trucho-951

Only 0.002, wow that's awesome! I was curious to see how this tool performed, so I ran a series of tests before setting the final tension and buttening up the belt covers.

In one of my tests, after using the wrench on the cam to turn in CCW and set preload on the belt (per instructions), I got the following readings with the reference bar: 0.350", then after waiting 30 seconds i got 0.352, after waiting 1 minute got 0.355, after 90 seconds i got 0.358, and after 2 minutes i got 0.358.

So that's a variability of 0.008 in just two minutes, without making any adjustments to the belt whatsoever, however that is still within the allowed 0.018 maximum variability for a used belt .

After running other experiments, I concluded that the camshaft will begin to rotate slightly CW over time and the belt "looses tension" (perhaps the lifters are bleeding down as the upper span of the belt under tension pulls on the cam CW). So to get consistent readings, it seems it's important to take readings immediately after turning the cam CCW to set preload.

The 902X tool is nice, I'm glad I got one, but it does have a definite learning curve. I spent a couple of hours just playing around with different belt preloading techniques in order to feel comfortable with the range of measurements, for example, I also experimented with turning the crankshaft CW to set the belt preload and to see how the readings varied, I got about the same range of variability.

Just out of curiosity, I checked the final belt tension with my Krikit, and lo and behold it was near the 40 lb mark!