Broken Bolt - Need Advice

[BimrFett]

I'll keep this short and rant-less.

While doing my T-belt/H20 Pump/VCG/Cam Seals, I snapped a small bolt (like an idiot).

Now which one / where is it, you ask? Well I was unlucky enough to snap one of the two M6 bolts that secure the Cam Seal housing to the head (Passenger side). Now the other side is intact. So far I have been very unsuccessful in drilling out the broken bolt-shaft. In fact I feel like I've made the situation infinitely worse.

I've considered reinstalling the Cam seal housing with 1 bolt - they aren't big bolts, they aren't torqued heavily, and the housing/seals are very tight in the head. However I worry about something coming losing and just effing the whole motor to Hades. This entire faux pas has left my entire project on hold for entirely too long. I'm quite frustrated with myself at this point. (Lesson learned, replace all old bolts when reinstalling)

Does anyone have any advice on how I should proceed.....? (Don't say motor swap)

Thank you in advance!

[MrBurgundy]

Pics, we need to see how bad you fucked it up.

These might work for you, but since you already "drilled it" who knows.

[e30davie]

Pics pics pics.

Not quite sure what bolt you are talking about, but worst case you keep drilling then run a tap through it and hope you got enough threads to hold it. or worst worst case drill it out the next size up.

[Kershaw]

This is going to not go well because the head is aluminum and the bolt is steel. The drill bit will walk to the softer metal. Your best bet may be to drill a small hole on the border of where the cam seal housing sits, tap it, put a washer on another small bolt and secure it like that. Or put it in with RTV, and then smother it with JB weld.

I don't think attempting to drill it out with it still in the car is going to be successful. As everyone else said, post pics and we can better advise you.

[Echo30V]

As stated above, please post a picture. I’ve had some recent success with stripped and snapped bolts. It would be easier to advise if we could see it.

[ttrousdell]

Pics, we need to see how bad you fucked it up.

Is there enough sticking out of the head to get vise grips on it?

[Andre3127]

Center punch the middle of the bolt, start with a small drill bit then work your way larger until you drill it completely out. Use a helicoil if all goes well, and if it doesn't you'll need a threaded insert.

One bolt would probably hold it fine, but if you can, do it right.

[jeffnhiscars]

Regardless of how, if the new bolt hole is not 100% concentric with the old hole, the seal will be offset and will a) leak and b) wear out prematurely.

[Kershaw]

You can open the hole on the seal housing and then use a washer to span the distance. That's not the issue.

The issue is drilling a harder metal out of a softer metal.

[MrBurgundy]

The inserts I posted above would probably save your ass, without damaging the threading of the aluminum head, but since you've already attempted to drill it out, there may not be enough meat for it to hold.

Really, the best thing for you to do right now would be to post a picture, then we can advise you accordingly

[BimrFett]

1) Thank you all for your views / replies and input,
2) Here are some pics of the situation...

As Kershaw said, the bit did have a tendency to walk into the softer metal of the Al head. Needless to say I stopped after the slightest incursion into the head.

I do have a set of drill/easy outs, but they don't fit in the well deep enough to reach the broken shaft.

I'm still leaning toward installing the seal/housing with the one bolt. It sits tightly in the head and under the end plugs, but that only if I'll be dealing with a small seep/leak of oil. I do have another M20 in a parts car that I can swap the head out with eventually, but it would need a rebuiled and I'm pressed to get the E30 running so I can fix the daily...

Any further input is greatly appreciated

[MrBurgundy]

Thats straight up fucked

[BimrFett]

Thats straight up fucked

Right?!?!? Ugh.

[cscracker]

It's hard for me to tell if that's a deep hole or a protrusion, but if it's a deep hole, you're pretty much screwed at this point. You should probably just pull the head and take it to a machine shop, they'll be able to get the bolt out and fill the void with welds, then re-drill and tap it for you. And since you'd be bringing them the head anyway, may as well have them clean it up and skim the mating surface.

For future reference, the best way to get a snapped bolt out is to build it up with a welder and use vise grips. The welding causes lots of uneven expansion to break it free, and the weld is strong enough to unscrew the remaining part with. In my experience, drilling never goes well and should be a last resort.

[potatomash]

Kinda looks like your best bet is to overdrill and retap the hole in M8. Theres no reason that wont work. If your not confident maybe get a machine shop to do it, they will come out to you usually if you ask them nicely :)

I'd say itl leak if you only use one bolt..