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What is the torque on the bolts that go into the tapered bushing on the spindle on an IS3000Z?
I've snapped one off before and don't want a repeat.
I'm having repeated problems with the driver's side (furthest left when seated facing forward) spindle.
This is the second time the keyway wallowed out and the spindle is loose.
It is the spindle closest to the tensioner pulley.
Is the bolt over the pulley on the tensioner bar (the bar that has the nut where the spring hooks over) supposed to be tight or is that bar supposed to have slack?

If you are talking about the nut that holds the spindle pulley on it is 85-90 lb/ft

ILENGINE said:

If you are talking about the nut that holds the spindle pulley on it is 85-90 lb/ft

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I added a picture. It's those two little bolts that presses the tapered bushing into the spindle pulley.

In your picture you have the 1/4-20 x 3/4 screws in the wrong holes. They need to be in the threaded holes of the taper bushing. If grade 5 you can only torque to 80 in/lbs.
The threaded holes in the taper bushing is for pressing out the bushing. And really you don't even have the keyway line up in your picture which should a hint that things are not assembled correctly.

Also please post the seven digit model number as the ones coming up doesn't have this setup which is very similar to ones that Scag uses on the STT mowers.

Also if Grade 8 screws. This is per JD 652R service manual.

StarTech said:

In your picture you have the 1/4-20 x 3/4 screws in the wrong holes. They need to be in the threaded holes of the taper bushing. If grade 5 you can only torque to 80 in/lbs.
The threaded holes in the taper bushing is for pressing out the bushing. And really you don't even have the keyway line up in your picture which should a hint that things are not assembled correctly.

Also please post the seven digit model number as the ones coming up doesn't have this setup which is very similar to ones that Scag uses on the STT mowers.

Also if Grade 8 screws. This is per JD 652R service manual.

View attachment 68655

Click to expand...

The Model is IS3000ZLKAV2661. In the picture, the bolts are in the threaded holes of the bushing. They go in the unthreaded holes during install into the pulley. The picture is just to show which bolts I'm referring to. I know they are in the take out position. I'll align the keyway when installing. 13-17 lb-ft is probably why I broke the bolt off last time. Pretty sure I did more than that. Thanks for the heads up. I appreciate it.

Tnx for the model number that tells me you had originally Grade 5 bolts which I would suggest upgrading to Grade 8. And yes if you just do it without a torque wrench it is easy to over torque them. I too had to learn to use a torque wrench on every screw as I was snapping off several every month until I did.

Ferris 5025010X8 BOLT, 1/4-20 X 1 GD5 superseded to 5025010X8SM​

Do not use grade 8 bolts unless you intend to increase the torque to the proper spec for a grade 8 bolt. Torque specs are specific to a fastener not application. The torque on the fastener will cause it to "stretch" to create the maximum clamping pressure that the fastener is capable of without breaking.Using a grade 8 bolt in place of a grade 5 will cause the bolt to not be in tension and will be loose. It will fail.

And many of torque wrenches out there they are not calibrated to within their specs either. I have return several new torque wrenches from HFT due them meeting specs. They should be within +-3% but when they are off by 10+-% this un-acceptable. One I returned was off by 25+%; otherwords, instead torquing to 20ft-lbs it was torquing to 25 ft-lbs and when set at 100 ft-lbs it was torquing to 125 ft-lbs. Currently replacement (another brand) is within +-1%. I use a digital toque adapter to check the calibration but I don't like using it for regular torquing as I can easily over torque trying to go by buzzer.

Another note all torque wrenches should be stored unloaded to prevent the calibration changing.

Ru4him said:

What is the torque on the bolts that go into the tapered bushing on the spindle on an IS3000Z?
I've snapped one off before and don't want a repeat.
I'm having repeated problems with the driver's side (furthest left when seated facing forward) spindle.
This is the second time the keyway wallowed out and the spindle is loose.
It is the spindle closest to the tensioner pulley.
Is the bolt over the pulley on the tensioner bar (the bar that has the nut where the spring hooks over) supposed to be tight or is that bar supposed to have slack?

Click to expand...

General guidance......

You can check and adjust your clickers with a good old beam style torque wrench in a pinch. They are still the most accurate and durable. There is a service in Beckley WVA that I have used to have them recalibrated. I have checked before and after with a beam style to confirm that it works. If you are in a business such as aero , then you would want the documentation. I think, for automotive and small engine you can be safe doing it yourself. The key being that you did it at all. As far as bolts and torque go, you can probably find a fastener manufacturers site and be able to get a lesson in nut, bolt and torque relationship. I took one years ago and it has made me a better tech, I hope.

StarTech said:

And many of torque wrenches out there they are not calibrated to within their specs either. I have return several new torque wrenches from HFT due them meeting specs. They should be within +-3% but when they are off by 10+-% this un-acceptable. One I returned was off by 25+%; otherwords, instead torquing to 20ft-lbs it was torquing to 25 ft-lbs and when set at 100 ft-lbs it was torquing to 125 ft-lbs. Currently replacement (another brand) is within +-1%. I use a digital toque adapter to check the calibration but I don't like using it for regular torquing as I can easily over torque trying to go by buzzer.

Another note all torque wrenches should be stored unloaded to prevent the calibration changing.

Click to expand...

I've never had an issue with HFT torque wrenches. I've got three of em and they're over 15 y/o. Only one got out of spec, the 3/8 torque wrench. But I calibrated it myself quite a few years back and it's still within specs. I've used em on many rods, heads, and other things that I wanted to be accurate with torque specs. I also have a beam torque wrench that's still very accurate. I often use it to make sure the HF torque wrenches are within specs. I've been wanting to try out one of those digital torque wrenches. I'm still researching the accuracy on them and how to calibrate it if needed though. You are correct about storing them unloaded too. Many times I've assisted other people and grabbed their torque wrench out of the tool box and it would set on like 95lbs. I'd ask them when was the last time they used it and they'd say something like a few months ago to a few years ago . I told em that it may/may not be accurate and need calibrating. If they still used it, well, I warned em.

Different story here as I have lost three in one year and got three poorly calibrated ones. Even the scales didn't line up on the last one. I gave up after three tries and brought another brand off Amazon.

But of I have 8 torque clicker wrenches now. In the 1/4, 3/8, and 1/2 square drives I both RH and LH versions. The 3/4 square drive I haven't need the LH one yet. And just got in a 10-70 inch/pound 1/4 hex drive screwdriver version yesterday. The HFT one only goes down to 20 in/lbs and I got some screws that are torqued at 15 in/lbs.