Anybody done this before???

[pawzbear]

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]

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

[cherrington17]

"Its so small!!!!"

...and for how many times we've heard pawz complain about that.... :rolleyes2:

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

[alerocar01]

I just want to know... how does one go about destroying a crank shaft?? I've never really heard of one breaking in 2... :huh:
i was thinking the same thing.

[pawzbear]

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

[pawzbear]

...and for how many times we've heard pawz complain about that.... :rolleyes2:


yeh yeh what can i say????

i need a stronger shaft.

[alerored04]

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]

105k miles.

[Mischief007]

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]

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

[Eh_nigma]

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]

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]

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]

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

[Eh_nigma]

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]

time for a full internal build then boost i say.

[pawzbear]

^^^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]

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]

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]

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

[Redog]

Ouch, I don't know if they make an aftermarket crank but they do make an aftermarket cams for the 2.4.

You give me dirty thoughts BTW :p

[Cliff8928]

didnt think a bump would have anything to do with cracking forged metal, though.

I'm pretty sure your crank shaft is cast, not forged.

[pawzbear]

^whatever, sorry.. i never claimed to be a crank shaft genius. Im no good with those details like that...

[Eh_nigma]

I just threw that one in there because it's happened...

[SweetNLow]

I'm pretty sure your crank shaft is cast, not forged.

ya its cast. BIG difference between cast and forged cranks.

i think this is simply a case of bad luck though. havent ever heard of somthing like this ever happening in a 2.4 thats for sure

[Spilner521]

It was probably just one of those one in a million chances of being a defective part from the factory. I've beaten the piss out of my 2.4 with a turbo and stock internals and haven't broken anything yet **knocks on wood**

[pawzbear]

^^ well thats nice to hear. new stock crank herrrrrre we go!!

[spyhunter]

It was probably just one of those one in a million chances of being a defective part from the factory. I've beaten the piss out of my 2.4 with a turbo and stock internals and haven't broken anything yet **knocks on wood**

Definitely can vouch for the stock crankshaft working just fine, only bottom end work is JE pistons and Eagle rods, granted it's all balanced but that's it.

I also have a verified 360+hp and 360+tq on this motor and growing, haven't broke the bottom end yet. The stock crank should be good for near 500hp, a few sources on j-body.org are claiming, but only like 1 guy on j-body has built a 2.4 to over 400hp that i know of. hah.

[pawzbear]

Well, apparently my engine block was worn or something as well...
My mom explained this to me secondhand from the machine shop and so sorry if it doesnt make too much sense...
Basically they bored out the block and are putting in the slightly bigger pistons.
woohoo what an engine mod!! im catchin up to the pack, yall.....

......kidding. =/

i just want my fucking car back, im sick of driving trucks.

[Gr1m]

yea i was so pissed when the body shop had my car for like a month and a half...although i got to drive around in a 07 TSX for most of it, but i still missed the 'ho

[jackal2000]

the block getting bored and honed is normal for high mileage rebuilds.

[pawzbear]

naaahhhh reallllyyyy =-P

[Ghadsphi]

I would have thought a cute girl in a truck was a stud magnent in N. Carolina... Shows what I know.

[cherrington17]

....shes a magnet for something... i'm not so sure its studs though.. :glare:



:lol:

[jackal2000]

naaahhhh reallllyyyy =-P

yes really. and just because the pistons are bigger doesnt mean jack. they will rip apart just as easy as the ones you had in there. switching out stock for oversized stock is not an upgrade.

[pawzbear]

i was being sarcastic jon.. i knew it wasnt a big deal and knew it was routine.. im not auto genius at all but that i didnt need schooling on =-P

[AlbinoMonkeyRat]

....shes a magnet for something... i'm not so sure its studs though.. :glare:



:lol:
probably got an extra vowel in there...............

just ribbin' ya, Candace. ;)

[Eh_nigma]

With the mechanics doing this, is it being possibly covered by insurance? Just something that happened to my old roomates Bronco... he threw in a rebuilt a few years back, this winter it had the same thing happen - minus the crank shaft breaking, but it was pretty damaged. They bored it out, however, under the cost of the repair, he threw in new forged pistons. Granted he had to add about $300, but the insurance claim covered the initial $900.

Just a thought...

And for the record, if you think driving around trucks is bad... my rental while the 'ho was in the shop... Toyota Echo. When I accidentally broke that, I went to a focus. Ford... Focus... yeah... so, minus Driving an old Datsun, I personally wouldn't mind hopping in a truck as a rental.

Anyway, yeah, just throwing the idea of some piston possibilities your way.

[pawzbear]

nah we got all the parts back now. and the work done on my car is virtually free anyways (except for parts)
The truck isnt rental anyways... its a spare one. we have a few trucks.. one for work, one for everyday driving, and the summer family ride/boat tow-er.
im rollin in the huge boat tow-er fit everybody-mobile.. the Expedition.


better than my old Silverado, eh Jon?
I loved that fucking thing.....

[pawzbear]

SOOOOOO apparently my engine is blue now? lmao.
the tech thats rebuilding my engine knows i love my bloo car, and since the black paint on the engine previously wasnt very pretty, he sanded it down or whatev and painted it blue for me. (uhm, k? black was fine but blue is cool....) We have high temp engine paint in all colors lying around, its not like it was a big deal. Its more of a grayish blue in person.. like my car.
Also i love my shiney NEW pistons and bored engine block.. its quite pretty.

I have Eibach springs, kyb2 struts, and front/rear strut bars coming in this week to be installed while its down.. might as well!!

[Oldsman]

looks like a ford blue

[jackal2000]

are those pistons flat top? i think i see a very small lip but im not sure....

[pawzbear]

uhmm i dunno i only looked at it a minute... i think its flat top... im not a piston genious however...

i think its a pontiac blue actually.. dunno!!

[ptrudel]

are the 2.4's supposed to have flat tops? cuz if ya my rev limiter def wasn't workin when mine blew up cuz there's valve indents in the piston tops

[spyhunter]

2.4's are flat top essentially... depending on where you get the pistons they'll either be 9.5:1 or 9.7:1... the older models used 9.5:1... they interchange with no problem, but you just can barely see the there's a slightly recessed ring in the piston for the compression change... FUN RIGHT?

btw, love the blue.