Broken bolt valve cover

[Jeff J]

98 Nissan Altima

One of the bolts snapped that hold on the valve cover.

I tried an extractor on it and the extractor bit broke and is still in the bolt. I’m not sure if I can dislodge it. I should have tried to clean the top threads prior to using the extractor. The bolt is not threaded all the way to the top.

What are my options here? Ultimately, I would like to remove the bolt and use a tap to rethread it. I could try drilling the entire broken bolt out. If I end up widening the hole, I will need to tap it and find a bigger bolt. Since the bolt is odd shaped. I don’t know if I will be able to find one.

Topic

[Joe Mama]

Here are two more methods I would recommend:

This is my favorite…

This is the oldest and most guaranteed to work method… this is a lot of work, takes many sharp drill bits and takes a long time and a lot of elbow grease & a lot of patience…

Removing broken bolts is a great skill to learn. The extractor is the first choice… but if that doesn’t work, either of these methods will get you the results you are looking for.

[Brian]

Valve cover bolts are designed to break if they are over torqued. Steel screw into an aluminum head. The steel screw could crack the head very badly if it were stronger. Lesson to anyone working with these, or oil pan or tranny pan bolts.

If the bolt is recessed below the top, it is obviously more difficult, but in my experience a broken steel bolt in an aluminum head is easier to remove than most think.

Spreay penetrating lube on it, or even drip a few drops of automatic transmission fluid on it. Let it soak a while.

The reverse drill bits from the local parts stores are not very sharp or sturdy in my opinion. If you have a local Fastenall store, know that they sell some of the highest quality drill bits that money can buy. If they have a small reverse bit smaller than the bolt, then buy a few if you can.

Get a small steel punch and tap right in the middle of the busted bolt to prevent the drill bit from walking (highly important). Make certain you hold the drill very square to the direction of the bolt, so you don’t drill sideways out through it. After getting a good start on this, let up on the pressure some. If you are lucky, it might walk right out as you reverse drill into it.

Know that if you twist the bit sideways, it becomes very easy to break, so hold it very straight all the time!

If you let the lube soak into it for a while, and the drill bit doesn’t walk off to the side, you will likely be able to screw it out with the reverse bit without damaging the threads.

[Jim Davis]

Since a part of the extractor is broken off in there, do you have access to a dremel tool? If so, try one of these: http://www.lowes.com/pd_93429-353-9910-03_1z140gkZ1z0wcln__?productId=1209993&pl=1
If you have an air compressor and a die grinder, you can get a carbide burr to fit it. You will need something like that to get that extractor out. With some care and making sure to stuff rags in the oil galleys, you can get the extractor and the broken bolt. As for the bolt, if you cannot find one at the dealer, just get the same size bolt and if you go to a good hardware store or lowes, look in the hardware/ bolt section and look for a piece of sleeve material that will fit over the bolt and cut it to the length you need and use a washer at the head if needed.

[Richard Kirshy]

Might look into this …
Rescue Bit
http://www.amazon.com/Rescue-Bit-Broken-Extractor-Removal/dp/B00B1E5APO

[Jeff J]

Thanks

I didn’t know about the dremel bits. I will try that and then try removing the bolt again.

[Author]

Replies