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Discussion Starter · #1 ·
When I pulled my clutch cover, I wasn't paying attention and removed the two bolts holding the engine side-cover that don't need to be removed. Put everything back, torqued to spec, no prob.

Yesterday when prepping for an oil change, I checked the bolts and found the one at 8 o'clock slightly loose, then realized it had stripped. I removed it and found a nice spiral of thread on the bolt. A bit shocking to me.

Not knowing the importance of this one bolt, I'm wondering what the best approach for repair is? Possible to use a longer bolt, or another simple/appropriate fix? Or is it more critical? I looked briefly at the heli-coil type fixes and thought of drilling, etc makes me very nervous...
 

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Without getting too technical, torquing bolts into aluminum can be problematic. If you mix a couple screws up and one is shorter, the shorter thread engagement will strip that one every time. So, first see if you have the correct length screw/bolt installed. Maybe you even have a lot of threads left if that is the case.

Now, since the bolt won't reach torque and then strip itself, you perhaps haven't developed a very good feel for this yet. Don't be shy about getting someone to help you if you decide on the heli-coil. The side benefit is that your assistant may already have the kit and you won't have to buy an entire kit.

Also, avoid lubrication on threads into aluminum. Even if you have a situation that requires some sealer, be careful as you can change the torque easily to beyond what the threads will take.
 

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Mr Leakered
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On my eBay motor, the PO or their shop stripped one of the valve cover bolts. The hole was drilled and tapped extra deep so just using a longer bolt is working for me. I torque it to a couple N-m less just so it lasts. No leaks.

Have a good one.
 

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Discussion Starter · #4 ·
So, first see if you have the correct length screw/bolt installed. Maybe you even have a lot of threads left if that is the case.
That's something I was wondering. IIRC, there are three different length bolts. Parts diagram doesn't help much. Does anyone know for sure which length bolts go in which position?

Now, since the bolt won't reach torque and then strip itself, you perhaps haven't developed a very good feel for this yet.
And that's what's weird to me. I snugged up all the bolts in a criss-cross pattern, then used a torque wrench in the same pattern to bring them to spec. Everything seemed fine at the time, and nothing was touched until just yesterday.

Thanks for the feedback thus far.
 

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Use one of the longest ones to find out how deep the hole is and when it bottoms you can measure how much you have sticking out so you will know what length to buy.
 

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A depth gauge (like what is used on tires) or a piece of wire (low tech) will show you how deep each hole is. Get a bolt that is a few mm short of the bottom of the hole.
 

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not sure which one you have issue with, but one of them has a dowel b/w cover and case and needs to be longer ideally anyway. i'd always go longer as first resort. if it's not there it might weep from the case/cover join.
 

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In my humble opinion many of the torque setting regarding alloy are pretty high.
If you take a say 5mm thread - #10ish from a reputable engineering website - they are talking about 19.2 inch / pounds, so converting to N/m say just over 2 N/m, if the maths is right.
What does the manual say for a 5mm Hex to alloy?
 

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Managed to dig this out of the manual, now that I had access again, saying M5 are 5N-m so on these small items 2.5 times..the 2N-m suggested.
 

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Discussion Starter · #10 ·
My shop manual specifies Clutch Cover Screws (6x1mm threading) specifically at 9nm.

And I can't tell in the torque tables what the other two case screws are called. 'Casing connection screws', maybe? I'm going to have to spend some more quality time with the manuals.

I have tentative plans to pull all the bolts again, measure the hole depth and go from there. But with my luck, I'll probably strip the rest of them somehow. So I might just do an oil change and ponder the rest...
 
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