I was just pondering on if anyone had blown a motor in the ss/sc LSJ?

 

No but mine sounds like complete **** right now. I am taking into service today. Sounds like the cat but then when I listen closer sounds like lifter s??? Im pretty pissed too because I just did all of these mods and now can't use them...... for now.......

 

The motor in my car blew. It is currently all torn apart at the dealership, and awaiting a complete new engine. By the way, all I had was an intake on it. I must just be the unlucky one who got a bad motor! Very aggrivating though!

 

What popped?

 

you dont think it was cause it was running lean or ne thing do you? what rpm where you at when it blew?

 

I started the car 10 minutes prior to leaving. I was driving to work. (I'm in the Air Force) I left the house. I was nice and slow through first. Then I gave it a little gas in second, and then I have to slow down because the street isn't long. As I was slowing down the car just suddenly died out before I stopped. Almost like it stalled. Then I couldn't get it started again. The dealership replaced the PCM first, as they thought it failed. The car still didn't start after that, so they took the valve/cam cover off and found the issue. One of the rocker arms had broke and twisted, and ground one of the cam lobes. A couple other rockers fell out of place too. They pulled the motor all apart, and found metal filings in the oil pan. At that point, the motor was pronounced dead.

The intake did not cause the failure because it ran fine for weeks prior to this happening. Know one really has a good answer for me as to why it broke. I guess I'm just the unlucky one here. Kinda sucks.

 

Thats sad to hear man, good thing you have warranty though. The engine went on my Caprice Classic a while back, as the original owners didn't change the oil in 100 000 kms!! Anyway, my engine just began revving unusually high then there was a small *bam*. Then my gas V8 engine sounded like a diesel engine. Turns out three pistons blew their seals and twisted the crankshaft also destroying my roller rockers and lifters...

 

Not to discount the suckiness factor, but that's an interesting failure. I'm getting the impression that our rocker arms are perhaps one of the weaker links in our engines. It's not the first time I have heard of failures in that part. Except the failure I've heard about had to do with the rockers not being set in place correctly following a cam shaft remove and replace. There really isn't anything in there that keeps them in place, they just kindda ride on the lifter, cam and valve stem. I'd be more willing to believe that the rocker fell out of place, and then got mangled by the cam shaft. Not sure why the other ones would have fell out though. Was the cam bent? Did the broken rocker move around and knock others out?

 

Correct me if I am wrong, but in DOHC engines, I thought there wasn't any rocker arms etc. I thought push rod motors had rockers and rocker arms...

 

yup we have rockers too the cam is what acuates them and no push rods

mrb

 

Its kind of a lever arrangment. The hinge point is the hydraulic lifter, the cam is in the middle, and then the valve stem on the end.

 

the reason i ask is because while i was out visting my cousin this past weekend i went for a ride in a cobalt ss.. Black g85 packgage really sweet. Anyway the guy gets on the high way and downshifted from fourth to 2nd and told me to watch. He revved the motor to like 7800 rpms i was astonished... after reading in the manual it states there is no rev limiter on 1st or second gear. originaly i thought that was wrong but i guess on the down **** the rev limiter is eliminated/ im too afraid to try this on my cobalt just wondering if anyone has maybe by accident had this happen to them or has done this!? I believe you have to be spining the motor over the 6800 rpm limiter to do this let me know?>

 

buddy's cobalt ain't gonna last long, and there is for sure a rev limiter as I've hit it a couple of times, oops.

 

Okey Dokey then that is going to be a toasted clutch, motor, pistons, EVERYTHING TOAST MAN !!

 

Ok, thats more or less what I thought...

 

In exactly what "manual" (and section/page#) do you claim to have read this ??
WopOnTour

 

i read it in the manual that came with my car as soon as i get home i will post it... as i dont have the manual on me! But i am not making this **** up, i saw it with my own face... it was crazy.... possibly a tach glitch?

 

Well my engine isnt blown turns out there is a problem with the tensioner for the timing chain. All fixed now. Now all I need to do is find an srt4 .... here turbo turbo turbo......

 

^^^^ Lucky duck!!!! I still have no engine in sight yet!!!!

 

The SS has a rev limiter that surely kicks in at 6500 rpms in all gears . Its a pretty aggressive one too , I dunno how ya missed it . Without PCM access to adjust the rev limiter I couldnt rev past 6500 if I wanted to or not .

A good friend of mine is a Saturn Tech , he replaced a blown engine in a 04 Redline , late in 04 . Thats all Ive heard about . If I remember right , he said it was a timing chain failure . And said it looked like the oil never had been changed , the car had almost 14K miles on it . Never truely made a exact diagnosis .

On the rockers , while I have no factual proof . I have heard the ecotec rockers are extremely weak pieces . One of the quotes I read was a guy hitting a rocker with a hammer and it fractured it , if thats the case , not good . If could whack the hell outa one my stock LS1 or LT1 rockers and it wouldnt fracture them . Its something I hope the aftermarket addresses sooner than later . I havent had the time to fully research just what kinda hard parts are out there for the ecotec engine ....maybe some of the more popular companies like comp cams or crane already has a ecotec rocker , as their are and have been for awhile high hp ecotecs in drag racing .

 

If you downshift into first and the wheels are spinning faster then the rev limiter would allow the engine to go, even if the limiter was working, the engine would still spin faster then that unless the clutch was disengadged.

 

Not me !

 

Question to the people who have blown the LSJ. What method did you use to break your engine in? The factory recommended way or break it in how you plan on driving it?

 

If you have to downshift to 2nd on the highway to hit 7800 rpms, that should tell you that maybe its not a good idea. Any motor will spin 8000 rpms if you throw it back in second gear at 80 mph. You might loose a rod or two as a result though. The rev limiter will work to prevent the engine from accelerating any faster once you are over 63-6400 rpms. If you use an outside force, in this case the momentum of the car, to overspeed the engine, cutting fuel or spark wont do a thing. I agree that the rev limiter should be set higher, but please tell your friend to stop trying to kill the engine. Thats all hes gonna do driving like that.