I changed my w/p and distributor seals and was trying to put the opti back on and broke the opti bolt that is on the driver's side. It was spinning in the hole with slight friction and then just snapped. I tried to EZ out it but the ez out broke in it as well. Here are my questions:

Can I use the next size bigger drill bit and drill out the hole and re-tap it?
Will the bit eat up the old screw?
Is there a bottom to that hole or does it just go to oil inside the engine?
If I drill it out, can I go too far and damage something?

And most importantly, should I just get it towed to a shop?

Thanks for any and all advice. In the Philadelphia area if anyone is interested in assisting

 

I used a drill bit and then inserted a bit that grabbed the broken part and removed it. The kit was from Sears and cost about $15.

 

Because you have broken the EZ out off in the hole, you problem now is MUCH worse. The EZ out is made of VERY hard material and is very hard to drill out. You will have to buy a few titanium drill bits to get it out.

Just out of curiosity, where did you find an EZ out that small? For and EZ out to work you have to drill out the center of the broken bolt, leaving the outside shell of the bolt for the EZ out to grab, I would find this almost impossible to do on a bolt that small.

That is a metric bolt in that hole, I would drill and tap it to the next size up STANDARD thread bolt. To keep as much metal in the hole. The bolts will not match but this is what I would do.

Worse case scenario is you will have to change the timing cover.



David

 

That's funny, mine had metric heads on the bolts but all the threads in the block were standard. ? When did it change?????? Why do we all buy 3/8 header bolts???? They wouldn't use metric and english together???

I doubt he's gona do a sufficient job at this point to render that hole useful. Since the EZ OUT has flutes on it. Try putting a couple of pin punches in the flutes and try rotating it clock wise to remove the EZ OUT.

Anytime you have a broke bolt, use the candle wax method. Heat the item so wax will wick into the hole then drill it with a left hand drill bit. It usually comes right out.

 

A veteran machinist once told me how he removes broken ez outs although I have never tried it. Heat the broken ez out till its cherry red, quickly shut off the gas and hit it with oxygen from the torch. The broken ez out should pop out like a bullet. I would pull the cover and try this on the bench and not on the car. I have drilled out a broken ez out before and it takes solid carbide bits which are expensive, titanium and cobalt bits barely scratch the surface. If and when you get the broken ez out removed try what speedy says with the candle & left hand bit method as some ez outs expand in the broken fastener make it wedged tighter and even harder to back out.

 

#1 this hole is not in the block

#2 if it has a metric head, it has metric thread

#3 All header bolts are standard thread on a small block Chevy, but again it is not in the block.


David

 

It was a 1/4"x20x2" bolt.

It was not an ezout, my mistake, it was just a left handed drill bit with nothing more than normal threads.

I am certain it goes into the block because the timing cover is not 2 inches deep even with the distributor.

Should I just try to drill it once more and really EZ out it plus the candle wax?

Thanks guys

 

What an A$$.

If the bolt in the timing cover is not in the block where is it? The transmission???????

Sorry but the bolts are all english size in the block. REGARDLESS of the fact that they have metric heads or not.

 

Hey feenix! before you ruin the TC cover, take if off the eng.. The bolt broken in the block will be much more accessible so you can remove it, it will probably protrude enough so you can use a small pair of visegrips on it, if not, at least you should be able to get the broken bit out and use an easeout or another LH bit to remove it. DONOT try the cutting torch method on a bolt that small on an eng. Danny Mc

 

It may go into the block THROUGH the timing cover..that is my bad.

BUT again, if it has a Metric head, it has Metric thread, as far as I know. Just because a metric socket fits it, doesnt mean it is a metric bolt

An 11mm-3/8, 13mm-1/2, 14mm-9/16, 18mm-3/4 are VERY close in head size. And will take the bolt out no problem. I will go look at my car to confirm.


**EDIT**
I stand corrected, it IS a 1/4-20 into the block.

But I also stand that if it has a metric head with a numeral designation on the top I.E. 8.8, 10.9 etc it is a metric head and thread bolt.

Standard head and thread bolts have a "slash" mark(s) on the top designated bolt grade or hardness I.E. 3 slashes is a grade 5, 5 slashes is a grade 8 and so on.




David

 

Also when you get it out, buy or borrow the correct "bottom tap" , run it in that hole to get it straightened up.


I am with Danny Mc on this one, that torch will ruin the timing cover.

David

 

My opti mounting bolts are 1/4-20 with 3/8 heads. Nothing metric about them.

 

11mm= 7/16
19mm= 3/4
13=1/2
14= shade smaller than 9/16


Get it right now!!!



I would pull the cover off....sounds like you should have enough there for some vise grips to work

 

You really want to get it right?

7/16 = 11.11250mm
3/4 = 19.05000mm
1/2 = 12.70000mm
9/16 = 14.28750mm