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Backing out broken bolts?

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Busted my valve cover flange bolts inside the cam cap. Yes, I was using a torque wrench and yes, I still managed to do it on both sides. :lol::p

Honda only sells the cam caps at part of the cylinder assembly, so I hope to be able to back the broken bolts out of the caps.

Any suggestions on how to accomplish this, or where I might best find someone to do it?

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find somone with some real experiance, even if you gotta pay for. like a very patient old man. i work as a tech at a harley/ buell shop and i have broken my fair share of stuff...more than i wanna remember. it depends how the break is to detemine the proper approach. send one to my message or this thread. i hope to see it again. i am new to this forum.

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you can buy extactors for this purpose, you need to be able to drill a hole into the broken bolt....the extractor will come with instructions on what size.....i just had to remove a broken clutch spring bolt....had a horrible time trying to get the hole drilled with multiple titanium drill bits...changed to carbide and it drilled easy....use a center punch to make sure you get started iin the center so that you don't end up drilling into the threads of the wall around the bolt....use oil to keep the bit from overheating.

once the hole is drilled the extractor goes into the drill..use the counter clockwise setting on the drill to reverse the bolt out

bye the way, I love the "very patient old man" suggestion.

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Seems like this is a recurring theme, I am beginning to wonder if it may be a good idea to just replace those bolts occasionally.

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But yes, the caps are a matched set to the head....so you only get one shot. An easy -out set can be had at Sears.Carefully drill center of the shank, deep enough for the remover to get a good bite. Tap the remover into the hole with a ball peen hammer and use a small cresent to turn it.

Stuff rags or paper towel around the area to catch the metal slivers.

If you have a drill press I would use it.

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inch/pounds, not foot/pounds?????

I hate 'EZ outs', they break easily and then you are in a world of hurt.

I start with left hand twist drill bits to drill the hole. They sometimes grab the bolt and turn it out. Then I use Snap-on bolt extractors. They are less prone to break. In a worse case scenario, I've had the local machine shop EDM out a pair of broken carbide pins in a flow meter. The same procedure can salvage most broken bolts. (And can do it to some really small ones, as well.)

The last time I had to pay to have it done it was $40. How much does a head cost?

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Manual calls for 7 ft. lbs., and I was using a 1/4" drive set at 84 in. lbs. - and the cylinder assembly is about $300. Someone who races in the same circuit I do says he can get them out easily... just need to find the time this week to drive an hour+ each way.

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Take the caps to a good machine shop. If they do any areospace work, they will have to problem. There are all sorts of incredible methods employed to remove broken bolts.

When tightening down shoulder bolts like these, do not use a torque wrench. Tight by hand until the should bottoms, then just 1/8 turn more.

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as stated try a left hand drill bit first, i have had good luck with these!

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So I'm guessing you didn't get to start it to see if the valves were the issue with the bike just stopping on you?

If you don't want to use a machine shop.

Try a left hand bit.

then an easy out.

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now why did they break? ... is it possible that maybe there was still oil in those "blind holes"? always make sure they are clear and clean. if there is any fluid in them you will "hydrolock" the bolt . running a bottoming tap to clear out any crap like old threadlocker or spider nests from an ongoing project is never a bad idea either....maybe i am slowly becoming the patient old man! good luck.

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Thanks, everyone. I found someone who also races STORM with me who owns a fabrication shop that focuses on motorcycles (Lone Star Motor Werx in Houston). I'll be going by with the caps in the morning, so keep your fingers crossed... thanks again for all the input.

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Is it me or I can see SAND in the picture of the Right cap?

Yes, there was some dirt on the underside of the frame that managed to drop off onto the caps when my ratchet hit the frame while loosening the cam cap bolts. Yet another hiccup in trying to get this bike back together... :p

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The bolt wont be tight, it shouldn't be bottomed out, it will come out easy once you get a hold of it. It twisted of because the cap made it tight and stretched the bolt.

Like meantioned by others, center punch the bolt as a bit guide, left had drill bit, then easy out. It may come out with the left had drill bit, that's why you should use the reserved bits because they heat during drilling (all bits do!) and turn it in the direction to loosen it.

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on valve covers and stuff like that I use my elbow as a torque wrench...I am a pro mechanic with Snap On tools and I cant tell you how many times I have broken bolts with a tourque wrench...(mainly smaller bolt sizes). Remember always stop a 1/4 turn before it breaks.

dont use caps from another head. The bores that hold the cam bearings are machined togeather. You might get away with it but it wont be right.

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the exact thing happened to me, brand new torque wrech set at 5ft/lbs (b/c i heard this was a problem) bolt snapped off

made the mistake of letting my bro try to drill and back out, drill bit slipped dug into the side and broke the casting at the top

had to get my brothers buddy to cut it off and weld around a bolt, just got it back i havent tried it yet, the threads seem stong

if you get new bolts thru honda youll notice they arent tapered at the top of the threads, where they all break off at i guess they noticed they ****ed up on the design

i was just pissed off that you cant buy cam bearing caps from Honda, apparently all of them are made slightly different and you shouldnt miss match

so you should definetly take it to a good machinist, i wish i did in the first place, woulda saved me alot of grief, plus i havent had my bike out once since i bought it in January...

good luck :p

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heres a pic of mine fixed, and the comparison of stock bolt and new one

cambearingcap002.jpg

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