: Cam Shaft Bolts!!!



[NortHStaR]
01-04-09, 10:42 PM
so the HG job on my 99 is drawing to a close, but today when I was running around and doing my final torque down and as I was giving the first bolt on the top shaft (closest to sprocket, top bolt) another hit with the wrench, the head twisted right off (i wasnt even pushing hard). Now its broken about halfway down so its not like I can just grab on and twist it out and replace.

Then to throw some salt in the wound when I gave up on that one I continued down the shaft and wouldnt you know it the last bolt (closest to the waterpump pully) does the same damn thing!! :banghead:

Now I was talking to my neighbor who has a 97 seville says that when he was doing his HG he did basicly the same thing (he busted off three bolts) he said that he just left it that way and his car runs fine, but I dont know if I wanna do that on my car.

So let me know what you guys think I can do any input is appreciated, cause Im going nuts!! :cookoo: :banghead:

Submariner409
01-04-09, 11:21 PM
Something's fishy......a bolt will not break when twisted to the correct specified torque.

You must remove the broken bolts and replace them with new units. Think of the upward force on each of those cam bearing saddles. Would you run the engine with only one connecting rod cap or main bearing cap bolt in place ?????

Time to go to NAPA or a big hardware store and get a couple of EZ-Outs.

[NortHStaR]
01-04-09, 11:31 PM
Thats what I thought, I knew that guy was a tad crazy.

As to something being "fishy" I'm not to sure what you mean, I wasnt hitting the bolt with any extream amount of force just making sure everything was tight.

dkozloski
01-04-09, 11:36 PM
;1725572']Thats what I thought, I knew that guy was a tad crazy.

As to something being "fishy" I'm not to sure what you mean, I wasnt hitting the bolt with any extream amount of force just making sure everything was tight.
A common problem with amateur mechanics is that they tend to overtighten everything. I've had many apprentices that I've had to educate in this area. It doesn't take much force to twist off small to medium cap screws. Go to Sears and buy one of their screw removing gadget kits. http://recs.richrelevance.com/rrserver/click?a=10153&vg=11d1def534ea1be0:-4dd5a68e:11ea4d01e45:-3182&pti=1&pa=side&hpi=1&stn=ClickCP&u=00004mJzNwCyWCozluoo7VgsBBu:139r4i8ml&s=00004mJzNwCyWCozluoo7VgsBBu:139r4i8ml&pg=20&p=00953153000P&ct=http%3A%2F%2Fwww.sears.com%2Fshc%2Fs%2Fp_10153_ 12605_00953153000P%3Fmv%3Drr

[NortHStaR]
01-04-09, 11:40 PM
Again I was not putting any hard force upon the bolt I just went through to make sure I didnt leave anything finger tight.

Submariner409
01-04-09, 11:42 PM
By "fishy" I mean just that: either bad (previously overstressed) bolts or improper torque.

Where did the bolt(s) break ?? The hex head area or the thread/shank transition ??

The FSM spec for camshaft cap bolts is 44 in/lb + 30 degrees. Tighten them all sequentially to avoid bending the cam(s).

[NortHStaR]
01-04-09, 11:49 PM
Within the threaded area, I do have a FSM and am doing everything to spec.

Thats why this has upset me so much, but whatever I will head out to the store in the morning for some EZ-Outs, nothing I can do about it now

97EldoCoupe
01-05-09, 02:05 AM
Rare occurances- the factory bolts sometimes will snap when being torqued to the factory specs. It's happened to me once or twice on cam cover bolts, luckily never on the cam bearing caps. Sub hit the nail on the head- previously overstressed. Again, these bolts are down in aluminum. Upon removal it is possible to overstress them because of the bolt seizing in the aluminum. Then when they go back in....

It's not necessarily Northstar's fault. Amateur or not- if Chacen (Northstar) does a Northstar HG job at the age of 16 he's pretty damn mechanically inclined in my books. You're doing great! Rule #1 in automotive repair, especially when it comes to engines, a snapped bolt can never be left alone. I think your neighbor is very lucky if his engine lasts- one loose cam bearing cap will result in a loss of oil pressure to the rest of them- the oil will bypass due to excessive clearances. And that's only the lubrication aspect of the situation.

Good luck with the project Chacen and keep up the good work!:thumbsup:

[NortHStaR]
01-05-09, 03:48 AM
Hey Jake, thanks for the pat on the back, I knew I couldnt just leave them like that, I knew my neighbor was crazy...

I should be coming up into your neck of the woods in the next couple months to see some friends that moved up there (in the caddy for sure). Maybe I can stop by and shake you hand maybe grab some lunch?? Also I read in another thread that you may be heading down to Texas for a little bit, let me know if that comes to be a reality. :highfive:

Also I will be hitting the key on the caddy for the first time in 3 months either tomarrow or tuesday, wish me luck!

97EldoCoupe
01-05-09, 10:36 AM
Northstar, if you drive through Ontario without stopping in at my shop I'll be p*ssed.....lol always happy to meet a fellow N* owner! I'd love to see your Deville!

With most N* HG jobs you prime the oil system, turn the key and it'll fire right up and smoothen out in the first 10-20 seconds. It's amazing how well they seem to fire-up/run after just being removed and torn down....

I'll keep my fingers crossed for you!:)

dkozloski
01-05-09, 11:02 AM
[NortHStaR], I meant my remark to be helpful rather than pure criticsm. I wish you the best of luck and if the bolts in question were pulled in two rather than twisted off they should come out easily. In fact, you might reach down in the hole with a sharp pointed tool like a scribe and "twiddle" them out.

[NortHStaR]
01-05-09, 01:22 PM
Thanks for the words of wisdom everyone, I will be heading down to the car to see if I can "twiddle" them out, and if that doesnt work I will be heading down to the store and grabbing some EZ-Outs.

97EldoCoupe
01-05-09, 05:33 PM
dkozloski is right- sometimes if it's a clean snap the bolt will just turn right out. Good luck.

[NortHStaR]
01-06-09, 02:35 AM
well today I got the EZ-outs and I cannot get the bit to stay square it just keeps on walking, so I ended up just drilling them out and cutting new threads.

Motor goes in tomarrow and should be done by wednesday for anyone interested.

97EldoCoupe
01-06-09, 10:53 AM
Always interested man!

dkozloski
01-06-09, 11:17 AM
;1726850']well today I got the EZ-outs and I cannot get the bit to stay square it just keeps on walking, so I ended up just drilling them out and cutting new threads.

Motor goes in tomarrow and should be done by wednesday for anyone interested.
Use a duplicating punch to start the hole in the middle. My Snap-On easyouts came with drill bushings to center the hole as well.

[NortHStaR]
01-06-09, 01:22 PM
I tried that last night dkozloski, No luck, but I drilled it out with a 8mm bit (I believe stock speck is 6mm) and put a larger bolt in, worked fine and everything is more than snug...

Thanks for the help everyone :yup: