So last night we had a little impromptu Prius modding meet-up. It seems ThunderJon has a friend who needs a BT Tech brace and a Coastal EV mod installed. I showed up to supervise, cheerlead, and provide V8CobraKid's torque wrench, which I had cleverly stolen after a previous meet-up. The EV mod went in first. ThunderJon is masterful at field-stripping a Prius dash by now having done his, mine, and who know how many others. He can take a dash apart with his eyes closed (maybe that's his secret). The EV mod went in and TJ didn't even get bit by the sleeping Prius. He's getting good at this. (Of course, I helped with my expert flashlight holding capability. I can hold the flashlight on a spot for minutes at a time.) Then we went to install the brace. "We" in this case is ThunderJon, who actually did the work under the car. First he undid the existing plate with his dual-mode monkey wrench. We carefully checked to make sure its length was designated in metric as well as English, since everyone knows you can't use an English-only monkey wrench on a metric bolt. Since it was designated as "200 mm" in addition to "8 inches" we knew the wrench was safe to use. Installing the BT brace turned out to be our downfall. "We" (TJ) got three of the bolts in without incident. But the fourth proved enigmatic. At first it felt "wrong" -- as though it was cross-threaded or something. Then it seemed to go in OK, if a little stiffer than the others. As TJ was carefully torquing it to the recommended 24 ft-lbs., it twisted off in his very hands. I knew TJ shouldn't have been bulking up at the gym at work. Viewed from 1000 feet, we might have resembled an anthill just poked with a stick. After the anthill settled down, we had a plan. We would go to Orchard hardware and get a screw extractor and a replacement bolt, then on to a friend's house who has a floor jack, stands, drill, pizza, and lots of beer. (The last two are my idea.) But at OSH we were let down. They had the EZ-outs (although a different brand which can't use that recognizable trademarked name). But a bolt? "Yeah, we're looking for a metric 6mm hex-head machine bolt that fits a Toyota." Not your everyday request at OSH, I guess. We looked at their selection of bolts, but didn't find any that looked like it belonged on a Prius. At that point we made a command decision to contact Brian and seek the real bolts before completing the installation. What went wrong? We're a little stumped on that one. True, TJ has biceps that look like tree trunks, but that's what the torque wrench is for. Did I steal a bad torque wrench from V8CobraKid? I'm pretty sure it's a good one -- and we've used it already on at least two BT installs. It's possible the bolt was somehow defective. But that seems like a stretch. So I prefer to blame it on everyone present except myself. After all, I was only the cheerleader.
Since you state that the nut/bolt felt "funny" coming off, it may well have been cross threaded when first installed - and twisted enough to start the "twist-off" effect. When you guys did your thing, it probably added enough twist to the already weakened bolt that it completed the twist-off job. Normally I feel little sympathy for those who refuse to accept responsibility for their actions, so I'm with you man: Way to go, TJ!
I was worried about this happening to me too! I just used a regular wrench until it was reasonably tight. As far as OSH, I can never find anything there! Home Depot has a much better selection, although you are usually on your own to find what you need!
i missed that little after party? we have planty of bolts at Ace hardware... OSH?... you won't find much there lol
That's what you get screwing around with your Prius's and bolting. You guys should be practicing safe Hex. But then again, its only 6mm, who would notice anyway?
<div class='quotetop'>QUOTE(jbarnhart @ Apr 16 2006, 01:58 PM) [snapback]240575[/snapback]</div> I found mine at my local hardware store.. its a standard metric thread.. its easy to find... just look for stainless. You should be able to find the exact screw in fact.... My hardware store is even pretty small and they had it. Getting the old one out will be your funnest trick.... Reverse drill bit may work, but if not, easyouts may be the trick.... I think thats what my mechanic used.
I received an email from Tony requesting a replacement bolt for the one he "twisted" off.. Please let me know if you still need this bolt as I can send one off to you tomorrow. If you notice we coat the bolts with a anti-seize grease to make it easier and more precise when you torque the bolts to spec. If one of the bolts snapped then chances are pretty good that it was torqued over 34 lb/ft. Also, if the bolt was cross-threaded then this could have contributed to it. In the many plates that we have sold I have only heard of this happening a few times and most admitted to not using a torque wrench and overtightening the bolt. Thanks and please let me know how you guys make out and if you still need me to send the replacement stainless bolt. Thanks!! Brian BT Tech 305-652-3115 <div class='quotetop'>QUOTE(jbarnhart @ Apr 16 2006, 04:58 PM) [snapback]240575[/snapback]</div>
Wait a sec, the bolts that come with the plate are rated to 34 ft-lb and we're putting 24 on them? Hmm, not a whole lot of margin for error. . Did it snap at the head, or down the threads a ways? . _H*
Great narrative, Joe <_< Brian, yes please we really could use another bolt. The bolt broke off about 1/4" down from the head, ugh.
This really sounds like a fluke. I hope the threads in the Prius aren't bad now. Of course, that can be fixed.
I specify 22-24 lbs/ft for the bolts. 34 lbs/ft torque is A LOT more torque than what is specified. Thanks!! Brian BT Tech 305-652-3115 <div class='quotetop'>QUOTE(hobbit @ Apr 17 2006, 07:42 AM) [snapback]240817[/snapback]</div> No problem Tony.. We will get one off to you today in the mail. Thanks!! Brian BT Tech 305-652-3115 <div class='quotetop'>QUOTE(ThunderJon @ Apr 17 2006, 11:38 AM) [snapback]240902[/snapback]</div>
<div class='quotetop'>QUOTE(hobbit @ Apr 17 2006, 06:42 AM) [snapback]240817[/snapback]</div> Also, stainless bolts are weaker than regular bolts - typically they don't even make it to SAE Grade 3. When I installed the plate, I canned the stainless bolts for a set of SAE Grade 8 capscrews - with anti-seize as well.
