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View Full Version : Crank shaft bolt broke?????? Why??



renello79
05-18-2012, 08:33 PM
Someone told me that when the tensioner goes bad it gets tighter and can cause the crankshaft to snap. Is this true and if not what would cause the crank bolt to just snap?

BECERRASC
05-18-2012, 08:44 PM
harmonic balancer is broken loose the belts then check the pulley see if it moves

David Neibert
05-18-2012, 09:27 PM
Someone told me that when the tensioner goes bad it gets tighter and can cause the crankshaft to snap. Is this true and if not what would cause the crank bolt to just snap?

No that's not true about the tensioner. Bolt breaks because the balancer is bad and is no longer absorbing vibrations from the crankshaft.

David

renello79
05-18-2012, 09:33 PM
I'm not doubting anyone's knowledge here, but ford said that I would feel the vibration if it was bad. That was not the case it was running perfect then I heard snap the bolt hit the ground and bounced and hit the underside of my car and it just died

SUPERVIC
05-19-2012, 06:46 PM
They will break if the bolt was loose

sts70004
05-19-2012, 07:10 PM
We've all been there before, get a new balancer and bolt. If you do it now, all you have to do is drill out the old bolt and use a balancer puller on the bad one. If you wait, it'll snap off leaving a tiny sleeve behind the timing cover and if you're lucky that's all.

sts70004
05-19-2012, 07:11 PM
I'm not doubting anyone's knowledge here, but ford said that I would feel the vibration if it was bad. That was not the case it was running perfect then I heard snap the bolt hit the ground and bounced and hit the underside of my car and it just died

When my bolt snapped I heard the same thing but mine didn't die for another three weeks. Back when I was uninformed about the balancers

renello79
05-19-2012, 09:26 PM
We've all been there before, get a new balancer and bolt. If you do it now, all you have to do is drill out the old bolt and use a balancer puller on the bad one. If you wait, it'll snap off leaving a tiny sleeve behind the timing cover and if you're lucky that's all.

Ok I got luckyish I have a tiny sleeve that broke off the harmonic balancer left on the crank. How the heck do I remove it?

90sc35thann
05-19-2012, 09:48 PM
If it were me. I would pull the timing cover.

renello79
05-19-2012, 10:12 PM
I am lacking the tool for the cam sensor. Is there a way to do it without the tool?

bowez
05-19-2012, 10:30 PM
If your talking about the tamper proof torx bit you need to get one, that is really the only special tool you need.

You could try and leave the cover on--wouldn't suggest it. Remove the the front seal and if you have a steady hand cut a notch in the sleeve and then remove it.

I'd suggest removing the cover and using a bearing puller--not a gear puller.

90sc35thann
05-19-2012, 10:45 PM
I am lacking the tool for the cam sensor. Is there a way to do it without the tool?

Mark the position of the outside of the cam sensor shaft housing relative to the timing cover and mark the inside (under the cam sensor) relative to the shaft housing. Reinstall aligning both marks. No need to adjust cam sensor.

renello79
05-19-2012, 10:54 PM
Mitchell says there's a alignment tool for the cam sensor if this is not a problem then great! How ever I am not willing to ruin my engine due to lack of information. So I turn to you guys this is proving to be the best resource for information on my car

ThunderRoad
05-19-2012, 11:28 PM
Ok I got luckyish I have a tiny sleeve that broke off the harmonic balancer left on the crank. How the heck do I remove it?

SCREW IN 3 SHEET METAL SCREWS:) AND GENLY PRY OUT:rolleyes: ALSO USE A REVERSE DRILL ON THE CRANK BOLT :eek:IT SHOULD SPIN IT OUT WORKED FOR ME:D CHECK SEARCH SITE ;)

Mike8675309
05-19-2012, 11:47 PM
Ford guy is unaware that the crank in your SC is internally balanced. The balancer doesn't actually balance anything on our car, it instead works as an inertial dampener to absorb detrimental harmonic vibrations that occur in the crankshaft. Thus no, you will barely notice if it is failing.

The bolt breaks because it is not supposed to be the primary means of balancer retention. The stock balancer uses a steel outer ring with a layer of elastomer and then a aluminum center section. As the elastomer wears and becomes damaged from oil and coolant leaks, it stops being effective. This will cause the aluminum center hub to expand enough that there is no longer a proper interference fit. This causes excess stress on the hub bolt, causing the bolt to fail. The primary retention method for the balancer is an interference fit between the balancer and the crankshaft.

Installing the cam sensor requires the crank shaft to be positioned at 26 degrees After Top Dead Center. Pictures in this thread make it clear the alignment you need, and highly accurate is not necessary. plus or minus a couple degrees won't impact anything.
http://www.sccoa.com/forums/showthread.php?t=40905&page=1&pp=15
If you pull the timing cover, don't forget the bolt on the bottom corner behind the oil filter.

Inspect the key on the crank before replacing the balancer. If it has become worn, you will want to replace it with a fresh new key.

the-big-e
05-20-2012, 09:07 AM
I'll second using the two or three sheet rock screws method.....

You can then use a puller to remove the ring.....

http://www.sccoa.com/forums/showthread.php?t=122769&highlight=puller

Taking the timing cover off has its own "alligators in the swamp"....

The long bolts that hold the water pump and timing cover to the block can sometimes get corrosion on them and snap off.....:mad:

renello79
05-20-2012, 06:02 PM
My baby is back up and running, I want to thank you guy's for all the advice. I wouldn't have gotten it done this quickly if I didn't have you guy's to turn to so thank you.

David Neibert
05-21-2012, 09:09 AM
My baby is back up and running, I want to thank you guy's for all the advice. I wouldn't have gotten it done this quickly if I didn't have you guy's to turn to so thank you.

Did you replace the balancer ?

David

renello79
05-21-2012, 01:23 PM
Yeah I put a oem balancer on for now but a BHJ is in the near future

sleeper bird
05-21-2012, 08:33 PM
my bolt also broke off,common deal i hear.

sts70004
05-21-2012, 09:11 PM
SCREW IN 3 SHEET METAL SCREWS:) AND GENLY PRY OUT:rolleyes: ALSO USE A REVERSE DRILL ON THE CRANK BOLT :eek:IT SHOULD SPIN IT OUT WORKED FOR ME:D CHECK SEARCH SITE ;)

I did the same thing, but used washers and the balancer puller to remove it. There is a thread with pics here on the site that tells you how to do it. Sure is easier than pulling the timing cover...