Anybody done this before???

pawzbear · 03-06-2007, 10:33 PM

So im coming off the highway yesterday, and all of a sudden my oil light blinks on. Well, that sucks. Especially when it starts knocking like a BITCH.
Pulled over immediately, check oil (doh!) its full b/c i just had an oil change 1,000 miles ago... so im like.. why did it lose oil pressure?
They take out my engine today, and when they do the end of my crank shaft falls off. Great. A 2 peice crank shaft!! wtf? Good(ish?) news the rest of the engine is in great shape. Just need a new shaft =) Check it out......

Also i was wondering if there were higher quality aftermarket crankshafts available for the 2.4L? B/c obviously the stock one isnt that great.

Here is some pics... ignore the last one. Was just goofing off with my exhaust manifold ("Its so small!!!!"). I'm used to seeing classic muscle car engine parts so my little engine cracks me up =)

diablo · 03-06-2007, 11:13 PM

Im also curious on where I can find a forged crank???...............wow man, at least you didn't hurt the block with that

cherrington17 · 03-06-2007, 11:19 PM

Quote:

Originally Posted by pawzbear

"Its so small!!!!"

...and for how many times we've heard pawz complain about that....

I just want to know... how does one go about destroying a crank shaft?? I've never really heard of one breaking in 2...

alerocar01 · 03-06-2007, 11:27 PM

Quote:

Originally Posted by cherrington17

I just want to know... how does one go about destroying a crank shaft?? I've never really heard of one breaking in 2...

i was thinking the same thing.

pawzbear · 03-06-2007, 11:37 PM

i dunno. im baffled, personally. i guess i just need a stronger one..

pawzbear · 03-06-2007, 11:39 PM

Quote:

Originally Posted by cherrington17

...and for how many times we've heard pawz complain about that....

yeh yeh what can i say????

i need a stronger shaft.

alerored04 · 03-06-2007, 11:50 PM

how many miles on it? Yeah that definately shouldnt have happened. A new replacement should hold up for you, its not like its making massive power that destroyed it. It is extremely weird that it broke like that and didnt put a rod through the block. But if there is a better one out there, my motto is, when shit breaks, upgrade it.

pawzbear · 03-06-2007, 11:52 PM

105k miles.

Mischief007 · 03-07-2007, 12:01 AM

Quote:

Originally Posted by pawzbear

yeh yeh what can i say????

i need a stronger shaft.

So so wrong....bad thoughts bad thoughts....I'm going to go put my mind into the gutter at this point.

I'd like to know how the crankshaft broke as well. How do you drive the car? Mileage?

Ghadsphi · 03-07-2007, 12:26 AM

Look out it's Lorena Bobbit! Sliced it clean off!

Eh_nigma · 03-07-2007, 01:47 AM

wow... I mean... wow... lucky? Yes, very. I think it's something to do with the headlights not being rotated, and the breaks not being lubricated. And small exhuast manifold on the 2.4? Ouch... I'll just drift back into the shadows with my 2.2...

As for why it happened, I can only offer two things. First, it may have been caused by the cranshaft nose. (Funny how working on old aircraft engines has FINALLY come to assist me here...) The keyway slot may be worn by the key in the crankshaft nose. This in turn may cause the pulley bolt to fail and begin slipping from the front of the crankshaft. This then in turn would cause an insufficient tightening torque on the assembly and eventually lead to metal fatigue and structural failure. This could also be caused by excess torque which will stretch the assembly and cause looseness... but, in a 2.4, not sure if there's enough torque. In a V-10 and V-12, running almost 2000hp, yeah, that was common.

The second thing, and I've seen this too, is simply caused by a junk shaft. If the rest of the engine is alright, and no small fragments were found chipping away at it, or burrs, or "dust" (caused by something wearing on the shaft), then this is evidence that that it was an immidiate failure. Makes me wonder if it was just that one particular shaft. Looking at the pictures of the shaft, I'm leaning towards that.

By any chance while coming off the highway, did you have your foot off the gas, and hit any potholes or a hard bump or anything like that?

Hope this helps a bit.

pawzbear · 03-07-2007, 02:06 AM

yeh i was decellerating and hit a lump of uneven concrete going kinda fast and as soon as i hit it the light went off. didnt think a bump would have anything to do with cracking forged metal, though.

Eh_nigma · 03-07-2007, 02:29 AM

may have something to do with it, but I know a buddy of mine and his gf were rear ended a few months ago. They're fine, however, their shaft snapped. Until the mechanic heard about the rear ending he was at a loss. HOWEVER, once he learned that, he figured that as the vehicle was still in motion, once they were hit, it caused the engine to lurch backwards. The added stress on the engine may have caused the shaft to break.

Though it was in a Grand Am, with a 4-banger just the same, you were not rear ended... but the thought did come to mind.

pawzbear · 03-07-2007, 02:31 AM

hmm yeh it does make sense. thanks for your help... still sucks about my engine rebuild though

Eh_nigma · 03-07-2007, 02:47 AM

No worries... but, look on the bright side, the rest of the engine remained undamaged. That buddy I mentioned, decided to continue driving his Grand Am with a knocking sound. I couldn't believe it. He actually said "Well, it still had power; not as much, but it still drove"... needless to say, his rebuild became a replace.

Good luck with it though. Although I'm sure that it wont happen with a new one, right now would be the oppertune time to look into getting something a bit better. But, that's just my 2 cents.

alerored04 · 03-07-2007, 03:21 AM

time for a full internal build then boost i say.

pawzbear · 03-07-2007, 03:24 AM

^^^lol that was suggested to me a few times tonight.

We had our Pontiac Club meeting at our shop tonight and my car seemed to be the star attraction.... a dirty alero with no motor sitting on a lift in the corner. Turbo?!?! no.. no turbo... too much work involved.
nevermind the WS6 TA over there.. or the hoard of GTO's, or the Judge, or any of the firebirds..... Lets check out the alero!!! lmao.

Eh_nigma · 03-07-2007, 03:29 AM

Judge? Somebody say 'The Judge?' and the flood of memories from the duster comes back kicking me in the nuts.

I say, once the rebuild is done, throw the smaller part of the crankshaft on a chain around your rear view mirror... sweet bling...

ptrudel · 03-07-2007, 08:44 AM

that's crazy...we're tied in damages i guess...i only took off the balancer parts from the rods/pistons being run into by them when they dropped through...shitty thing is i gotta do another engine swap cuz the second motor i put in ran for 5 mins and now it knocks too...that's what i get for gettin it from a "buddy"

p1mptress · 03-07-2007, 10:06 AM

Good luck hope your hoe is back on the road soon!