Just twisted off an intake manifold bolt!!!

[ubtripn]

Great point, I just replaced the PCV for that exact reason but was still leaking oil.

I am going to have to do the job tomorrow, started the engine today just to observe how bad the leak would be and it is totally sealed up. For now. If I run it that way I gather that i could lose the engine or warp the manifold. The black Permutex worked on sealing off the oil though but I am going to get the oats stuff that was recommended.

[60ratrod]

well did you let her run until she was warm?? cause that's when everything expands and when you will find your leaks. check the oil and see if it's milky

[ubtripn]

Ran it only for about 3 minutes.

[ubtripn]

Just brought the truck up to full temp, 90 outside as well. Ran it for 20 minutes, multiple revs - no leaks. Oh well, it doesn't really qualify under the - "if it ain't broke don't fix it rule" because it can apparently go at any time and knowing Murphy's law, it would be a bad time. Plus, the bolt is broken. =) I had a feeling it would hold, I just don't know for how long.

[60ratrod]

again does the oil look milky?

[ubtripn]

Nope, no oil in the water or water in the oil.

[ubtripn]

Well, started the job today. Will be asking questions I'm sure.

[Dark Knight]

I see no one mentioned not to use the cheap gaskets that come in the kit for the ends of the manifold. Use a good silicone instead. Those gaskets tend to leak oil after a while. Don't know if you knew this or not, but if you did a friendly reminder can't hurt.

[rsavage]

I would check all your bolts once you remove the intake. There had to be a reason why the bolt snapped off and it was probably due to it being too long and bottoming out. If the intake was off previously, the wrong length replacement bolts could very well have been used. I have never had to use sealant on intake manifold bolts. Good luck on removing it. Patience is the key along with many applications of good penetrant over time. If you force it, it may twist off again flush leading to a drill out/tap cleanup as your last option. You are going to have to be super careful about any metal filings getting into the engine as you work on it with the head still on the motor.

[MrGoodpliers]

Okay, this one is going to sound silly, but I swear it has worked for me more than once. Take a rag or paper towel and twist it in the hole. She may back right out!

[OhOneWS6]

Originally Posted by 71tahoe

You should also investigate why there is enough crankcase pressure to push oil out the intake bolt holes. Make sure your PVC system is working.

The center bolts holes on a Chevy intake are open to the push rod passage. They will seep oil if thread sealant is not used. PCV only works at idle. After that it is the breather tube going to the air cleaner that takes over crank case evac.

To the OP. Now that the head is broken off the torque is released off the bolt. It may come out easily once the intake is off. I would replace all the intake bolts. It is possible that that intake bolts were over torqued by a PO causing it to fail. If one was over torqued chances are good they all were.

[68 TT]

Originally Posted by El Jay

Good advice.

To add a bit to it, I'd have everything set up & ready to go; bolt center punched & the drill loaded & ready to go.
After heating the bolt, I'd hit it with a candle to get some wax down into the threads & then start drilling with the reverse twist drill. The tip of the bolt is a little harder than the rest and when the drill hits the end, it will try to bind & back the bolt out.
If this doesn't work, then you already have a hole drilled for your E-Z out.

I was a machinist in the air force for 13 years and removed on average 20 broken or damaged fasteners per day.

Make sure you use a die grinder with a ball end carbide cutter on the head of the broken off bolt. The irregular surface will damage your drill bit and/or make it walk to the side damaging the intake.

Make sure you are drilling perfectly parallel with the center line of the bolt with the left hand drill bit or it will break the drill bit when the bolt starts to come out.

A 1/4" left hand drill bit will work well on the 3/8" intake bolts.

If you have a hammer drill use it. The shock will help break the fastener loose.