valve cover bolt snapped

[PlanZero]

After replacing the valve cover gasket and tightening the bolts in the proper order, the last bolt snapped. Must've been on it's way out. I tried to drill out the piece but accidentally drilled along side since the bit slipped through that soft aluminum like butter. So now the hole is slightly off and I couldn't replace the original plug and bolt ( got a replacement @ junkyard). I wound up having to use a regular bolt and washer to hold that corner in place, and now I have a leak because I either can't get proper torque or the absence of that plug/ washer is preventing the cover from sealing properly. I can see the leak behind the bolt. Any suggestions?

 

[Insane20]

Why not get a tap and tap new threads in that hole.

 

[PlanZero]

I kinda passed the point of no return I think. There is now a new hole right next to the snapped bolt, so if I tried to tap I'd have an even bigger hole.

 

[bryanwheat]

Either drill and tap a larger hole and use a longer bolt or use a heli coil or timesert.

 

[PlanZero]

Don't know if 4g63 covers have the same bolts as 420a, but there is a cup like washer that rests in the recessed hole, which the bolt goes through. My problem with my replacement bolt and washer is that it isn't holding the VC down properly. If I use bryanwheat's method, won't I still have the same problem?

 

[Miasma]

If you align the VC with the head, and drill a larger bolt hole into both, then tap the cylinder head bolt hole you should be able to torque the VC down properly. Just go slow and don't aggresive so that you don't crack the VC or ruin the head.

 

[dsmcrzy]

OP I don't use those rubber grommets in the bolt holes at all and I have zero valve cover leaks. The absolute key is to torque it down in the 3 steps like it has in the manuals. U could use a through bolt or some helicoils. With the little but of torque the valve cover bolts see you might be able to get away with some JB weld to fill the hole and the. Re drill and tap that. Just a thought if all else fails.

 

[2slow4now]

Probably won't help but if you do have a bolt snap in aluminum and you can get to it with a welder just weld on top of the broken bolt which heats up the aluminum and gives you something to grab hold of with vice grips to be able to back the broken piece of bolt out. The problem would be making sure to not get any junk in the head when you weld. Then the extra hole to the side of the bolt hole. It will have to be filled. JB weld, marine tex, or weld up the aluminum. Maybe even high temp silicone in the hole and on the bolt threads but it very well might still leak.

 

[PlanZero]

Thanks for the input guys. I gotta wait til the weather breaks a little ### unfortunately I gotta do my repairs outdoors. Luckily, the leakage is minimal but still noticeable. It's hard to tell how much
Has spread down over the exhaust manifold and thermostat housing. It's also allowing moisture in, as evidenced by the condensation under the oil cap. Is there any danger in this?

 

[gieri002]

No, as long as you keep checking your oil levels you will be fine.

 

[Liltazz803]

Ill just get a new one