So I recently bought my wife a GX470 with three broken skid plate bolts. I searched the sight and did not find very much in the way of complete info so I decided to share this little how to.
First and foremost DO NOT use a bolt extractor. I tried two on two different bolts and they both snapped, making my day longer than I had cared it to be. Bolt extractors are good for broken bolts. Not seized bolts.
First the tools.
One VERY important thing not pictured is a good pair of goggles or safety glasses, metal shavings in your eye will ruin your whole day.
One optional item you may need is a roll of nickels. If you decide you want to use an extractor it'll cost you about $3.50 for the swear jar when you break it off.
A 3lb hammer and a center punch to dimple the center of the bolts so that when you start drilling you bit wont wander and stay centered. Continuously keep checking your hole to make sure you are centered. If you are not, it is easy enough to tilt your drill, work your way over to the center, then re-adjust.
You will need a couple of decent drill bits in different sizes and a good drill. Make sure none of your bits are larger than the core of the bolts that should go in. The idea is to drill away all but the threads.
One thing I found extremely helpful is the use of a small floor jack. Once you get the hole started, you can use the floor jack to gentle ease the bit up. I did not need any lube for the bolts. So just dry drilling is all you need.
Once you get a hole drilled through the center, use progressively bigger bits until you have drilled out most of the bolt. This pic is actually when I drilled out the bolt extractor, but you get the idea.
Then place the point of the center punch between what is left of the bolt and the frame. Pound in several places to separate the threads from the frame. in all three instances, what was left of the bolt was punch through into the cavity of the frame.
Once that is complete, use an 8 mm tap to clean up the threads.
Once that is done, use the tap and wd-40 on all of your other non-seized, non-broken bolt holes. Chances are they are pretty narly too. here is what I got out of one of the non-problem holes.
After that I reinstalled with aftermarket stainless steel M8-1.25 x 20 bolts and of course anti-seize. I have seen others recommend M8 1.25 x 25. Those are too long and I think that is part of the problem. The stock bolts are that long and they sit above the hole, exposed and rusting, which might be part of the snapping issue.
FYI, when drilling out the hardened bolt extractor. I needed a carbide tip, cooled with WD-40, running on the highest speed of my drill. It took a while and a couple of bits, but it came out.
Here is all the dum dum I removed from the skids, oh and the safety glasses I used. And yes, that is my precious moments coffee mug in the background...
First and foremost DO NOT use a bolt extractor. I tried two on two different bolts and they both snapped, making my day longer than I had cared it to be. Bolt extractors are good for broken bolts. Not seized bolts.
First the tools.
One VERY important thing not pictured is a good pair of goggles or safety glasses, metal shavings in your eye will ruin your whole day.
One optional item you may need is a roll of nickels. If you decide you want to use an extractor it'll cost you about $3.50 for the swear jar when you break it off.
A 3lb hammer and a center punch to dimple the center of the bolts so that when you start drilling you bit wont wander and stay centered. Continuously keep checking your hole to make sure you are centered. If you are not, it is easy enough to tilt your drill, work your way over to the center, then re-adjust.
You will need a couple of decent drill bits in different sizes and a good drill. Make sure none of your bits are larger than the core of the bolts that should go in. The idea is to drill away all but the threads.
One thing I found extremely helpful is the use of a small floor jack. Once you get the hole started, you can use the floor jack to gentle ease the bit up. I did not need any lube for the bolts. So just dry drilling is all you need.
Once you get a hole drilled through the center, use progressively bigger bits until you have drilled out most of the bolt. This pic is actually when I drilled out the bolt extractor, but you get the idea.
Then place the point of the center punch between what is left of the bolt and the frame. Pound in several places to separate the threads from the frame. in all three instances, what was left of the bolt was punch through into the cavity of the frame.
Once that is complete, use an 8 mm tap to clean up the threads.
Once that is done, use the tap and wd-40 on all of your other non-seized, non-broken bolt holes. Chances are they are pretty narly too. here is what I got out of one of the non-problem holes.
After that I reinstalled with aftermarket stainless steel M8-1.25 x 20 bolts and of course anti-seize. I have seen others recommend M8 1.25 x 25. Those are too long and I think that is part of the problem. The stock bolts are that long and they sit above the hole, exposed and rusting, which might be part of the snapping issue.
FYI, when drilling out the hardened bolt extractor. I needed a carbide tip, cooled with WD-40, running on the highest speed of my drill. It took a while and a couple of bits, but it came out.
Here is all the dum dum I removed from the skids, oh and the safety glasses I used. And yes, that is my precious moments coffee mug in the background...
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