0 compression on motor - non f-body

[BAS]

Timing chain was acting up.. getting noisy. Girl ran it with little oil. Found some plastic
in the chain on tear down. (thought it
was metal at first). Had originally thought
the chain broke.

Tested compression. I have 0 compression in every cylinder (95 saturn SOHC).

So I figure the chain jumped or something
funky. I tear it all apart. Didn't note
were the timing marks were, but when
I went to reassemble it today, after reading where the marks where for
timing, I noticed it was off. The right
plastic chain guide was missing and busted
off. I replaced the chain, tensioner,
chain guide and sprockets and set
the timing correctly.

Still NO start. NO compression in #2.
(Didn't want to bother to test the otheres.).

I guess my question here, is that
without compression, there isn't
any chance of a cylinder firing?

It appears that no cylinders are firing..

I don't know if there has been valve
or piston damage. There is nothing
hitting (before) or now when I crank
it or rotate it.

I imagine the engine is toast with mechanical problems.

[N20LT4Bird]

If the timing is correct now, and still no compression, then there is an internal problem ranging from headgasket, to piston rings, bent valves (from timing chain jumping) etc. Check all of the cylinders for compression, if they are all without compression, this limits the number of possiblities for the problem. Did you do a wet compression test (spraying oil in the cylinders)?

[tabahr]

Re: 0 compression on motor - non f-body

Originally posted by BAS


I guess my question here, is that
without compression, there isn't
any chance of a cylinder firing?

For any internal combustion engine to run, including rotary engines you need 3 things.. Without all 3, there is NO chance.

1) spark (unless it is a diesel)
2) compression
3) Fuel

Any time you have an engine that will not run the problem will be one of the 3. Are you absolutely sure you set the timing right? If there is still no compression in all the cylinders I would say the timing is off yet. I find it hard to believe the rings are so trashed there is 0 compression.

There is a possibility that when the timing slipped the valves crashed into the pistons and got bent up. This will happon on interfenence based engines. I'm not sure if your engine is interference or non-interference. If this occurred, you will get 0 compression even if the timing is correct.

[BAS]

Re: Re: 0 compression on motor - non f-body

That's what I was thinking ( spark/fuel/compression) needed..

I'm 100% sure the timing is on..
Was at TDC #1, and camshaft was straight up as manual said.. Had the chain set perfectly ( up top (12 oclock), and below (6 oclock on crank)
with color code chain segments)..

I can still turn the crank by had at
the fly wheel pretty easily. I'm still
amazed by this. It is so much harder
to turn my 8 cylinder f-body with a
breaker bar...I can feel/hear the
compression in my LT1.. but this
car, NOTHING...

I wish I had time to tear it apart though.

I'm not in the mood for tearing the
timing chain back off and then pulling
the head off.

I thought it would be non interference,
but everything I've read only said to
be careful with hitting valves with
the chain off and turning the crank.
I did confirm that something would touch and not allow movement when this
happened.. (I had to move the crank
and cam into position slowly )..

I at least have fuel to the fuel rail,
pulled the line off, and it turned
the ignition on and it dumped fuel
onto the motor..
have some spark.. put a gap checker
on it and it sparked .. probably needed
to make that gap bigger...but there
is spark..

It's been a really Long day

Originally posted by tabahr
For any internal combustion engine to run, including rotary engines you need 3 things.. Without all 3, there is NO chance.

1) spark (unless it is a diesel)
2) compression
3) Fuel

Any time you have an engine that will not run the problem will be one of the 3. Are you absolutely sure you set the timing right? If there is still no compression in all the cylinders I would say the timing is off yet. I find it hard to believe the rings are so trashed there is 0 compression.

There is a possibility that when the timing slipped the valves crashed into the pistons and got bent up. This will happon on interfenence based engines. I'm not sure if your engine is interference or non-interference. If this occurred, you will get 0 compression even if the timing is correct.

[Torque]

To get absolutely 0 compression you usually have to have bent valves. Even with timing off, if your valves are sealing at all, you should get some reaction out of your guage.

My bet is that it is a crash valve motor and your valves are bent. If this is the case you should have 0 compression. What were the symptoms when the motor quit?

[BAS]

I wasn't there, but she said it just quit.

I asked her if it went boom or anything,
and she said no.

women!

Originally posted by Torque

My bet is that it is a crash valve motor and your valves are bent. If this is the case you should have 0 compression. What were the symptoms when the motor quit?

[Torque]

That's the worst when you have nothing to go on, when you are not there. I hear you, not to generalize, but my wife definitely could do a better job paying attention to these things.

I can't beleive the times I get in her car, take off down the freeway, and say, hey, how long has the steeringwheel been vibrating two inches back and forth at 70? Oh, yeah, been meaning to tell you about that, couple months now.... okay! Time to get the tires balanced...

Good luck with the saturn. If you have to replace the motor, I bet one of those would move pretty good with a small block!

[Rekisito]

Good luck fitting a small block in a saturn. Right now I'm considering dropping the 3800 SC series motor in mine.

[Torque]

Wow! I was kidding, but I guess people actually stuff bigger motors in there. Saturns are FWD right? You leaving it that way?

[Rekisito]

yeah FWD, and will leave it that way. A conversion would cost more money than I can afford right now. Right now I'm caught between stuffing the 3800 in there and stay with the auto tranny, or for Saturn to release the Ion Redline with the supercharged ecotec. I'll probably end up going with the ecotec, since they're supposed to be capable of handling up to a 1000HP.

Anyhow, these are just future plans for when I finish college, right now I have decided to keep the car and do a budget turbo setup on it. Small used (rebuilt) turbo, something that spools up quick, and all the various other pars I'll need. I'll have to get a turbo exhaust manifold custom made, that will probably be the most expensive part. Once I finish I'm hoping for high 14's with my crappy autotragic. I'll only be running like 4 or 5psi since my motor is not built up.

I'll have to wait to finish college and get a decent job before I get my F-body.

[Torque]

Not to sound like the wise old man on the soapbox ('cause I'm not wise and not that old!). If you can swing it, don't spend the money on the car, finish school, get a good paying job, buy a car and do it right the first time.

I bought my '96 in college. Did a bunch of nicle and dime stuff with the money I could scrounge together (cold air induction, flowmasters etc.) and got down to 13.6 @101.3. It was cool at the time, but, looking back on it, if I did it all over, I would have been much better off saving the money and putting it in right all at once and I would have had just as much fun in the 14's.

I was lucky to get a great job out of school, built a killer motor, basically built my dream car (although this definition continues to evolve). In the process however, I ended up replacing all the small stuff I did while I was in school and then I have pretty much done everything twice while learning things the hard way here and there. I would hate to see you blow a ton of money on a turbo, then have something happen to the motor, now you are off the road or spending more money etc.

Then again, you probably don't have my luck so everything would probably turn out fine. If you are like me you'll trick out your Saturn anyway (that's what I would have done!!). Good luck with it either way!

[Rekisito]

Hahaha I have HORRIBLE luck when it comes to my car. My turbo setup won't run me much more than a grand since it will consist mostly of used parts. Right now my best quarter time is a 16.3 with nothing but intake and a catback exhaust. If I can get low 15's or even break 14's out of it I would be happy. I really desire a fairly quick car for the time being. I'd really be happy if it was a manual but that will wait.

In general I just want a decent car. Before I start the turbo project I have to get my headlight fixed since I hit a dog doing about 70mph on the highway, replace my corner lights (dog), and just some light work on the fender. My car held up really well considering how fast I was going (I was within the limit though) and the fact that dog weighted almost 200lbs. My interior needs a little work too, and I REALLY would like a semi-nice system cause my speakers aren't really cutting it with the bass anymore.

In a way it is kinda wasting my money, but it gives me something to do and have fun with. I'm not exactly a tech head when it comes to working on cars but I love the feeling after working on my car and everything turning out successful. Driving is also one of my FAVORITE things to do whether it be just cruising, or on occasion showing your usual cocky rice-boy what's up.

If my motor takes a dump on me for some reason I'll have a crappy old nissan in the garage as a backup car.

[Torque]

Sound excactly like me when I was in school (except for the dog part). One thing I will say, if you do a nice stereo, you can make it last forever. I did a killer stereo in my car when I was in school. My parents, even some of my more gearhead friends did not understand and thought I was wasting my money.

Well, I still have all my components, most of them are in my boat now (stripped the car when I put it on a diet), and all those (inclusive of my parents) really enjoy cruising in my boat while listening to some tunes! Unlike high performance car stuff, stereo stuff should not blow up if you do it right, and will last forever and can be enjoyed forever if you take care of it. I still never regret a dime I spent on stereo stuff...

Glad to hear you have a beater in the garage in case something bad happens... I did not tear into my car until I had a backup.. .boy did I need it!

[Rekisito]

Right now I have Infinity 6.5" reference series all the way around, they throw a lot of bass considering it's just a speaker but I want more bass. I have a Kenwood deck, don't know the model off hand, but it has MP3 CD playback capability, which means 150 track CD's, which are GREAT for road trips.