What sounds like a timing belt, but isn't....

[packrat]

Alright, so after poking around for the past 24 hours, I haven't come up with much on the forums or through google.
I'm runnin' a '94 tsi, and last night I stop at a light and she just dies. Try to start her up and it sounds like there's a bit of compression but it's weak. I push her to a parking lot where I could see a bit, and I pop the oil cap, note where the lobe is, spin the starter....and the cam doesn't spin...So I panic, and think shit, the timing belt broke. (This shouldn't have happened as it only has 40k on it). No clunking sounds or anything, she just puttered to a halt).
Car get's towed home and I poke around a little bit more. I don't see any shiny bits in the combustion chambers, and even more curiously, I pull the upper timing cover off, fully expecting to find a broken timing belt...and it's still there, tightened up and looking quite healthy...
Now I had a broken timing belt on a ca18de before, but when it broke it just sounded like a whizzing noise...the noise coming from the 4g63t sounds like it's trying to do something, but the cams won't spin when the starter is hit...(Timing marks are: Exhaust at 3:00 and intake at 9:00)...
Someone wanna explain what the hell kinda voodoo this is here?!
Thanks,
Packrat

 

[92AWDHX40]

First do a compression test.

 

[WES_393]

So the cam gears don't move at all? Have you checked the crankshaft sprocket that drives the timing belt? It sounds like you broke some teeth off the belt or lost tension at the crankshaft.

 

[constant_proj21]

Id just try and turn it over by hand with a ratchet and see if you banged valves.

 

[packrat]

Extremely limited on tools out here guys...all my tools are at my garage in PA with my Nissan and I am 200+ miles from there.
Can you loose tension down there and still have tension upstairs, so to speak? I've never seen the bottom of this engine before...on a ca18de/t that wouldn't be possible, so I am a little baffled as to how that could happen. The belt does indeed look to be in good shape, no cracks or anything, and this car is bone freakin' stock, and no I wasn't even doing anything stupid in it. (I just coming home from work).
I have no compression tester right now, and no jacks/jack stands....

 

[TAL0NTSi]

It's going to be tough to come to any real conclusion without a compression tester or tools. I recently ran into a situation where my intake cam seized in my head and caused the same symptoms you're describing. I would suggest stopping by AutoZone and picking up a compression tester, I got mine for like $20.

 

[96 420a-t]

If you sheared the teeth off of the belt at the crank pulley tou would have your symptoms axactly. I would look there.

 

[2gTurBoD]

Are you sure your starter is coming out? It could just be spinning but not engaging. Just my .02 cent. If something was stuck id imagine you'd know fairly quickly. Check your crank sprocket if your able to.

 

[packrat]

Are you sure your starter is coming out? It could just be spinning but not engaging. Just my .02 cent. If something was stuck id imagine you'd know fairly quickly. Check your crank sprocket if your able to.

Wouldn't this sound more like a whizzing noise?

I dunno how I'm gonna check the crank sprocket with so few tools and no way to jack the thing up :/...

It's going to be tough to come to any real conclusion without a compression tester or tools. I recently ran into a situation where my intake cam seized in my head and caused the same symptoms you're describing. I would suggest stopping by AutoZone and picking up a compression tester, I got mine for like $20.

Well if the cams aren't moving some of the cylinders are going to have crap for compression...
I don't know...
What's the balance shaft thing do?
Anyone have a picture of the timing side of an unmolested 4g63t?

 

[2gTurBoD]

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What if anything is moving? Is the crank pulley moving? You dont have at least a breaker bar to rotate the engine, a wrench or something? Someone around has to at least have one tool they would let you use.

Without taking it apart, it would be difficult to just sit and guess. It could be alot of things that have been mentioned.

At least see if you can get some type of wrench or something to rotate the engine over and that would at least let you check the timing belt.

 

[jimbob_843]

Timing belt probably jumped some teeth, causing valves to hit the pistons and caused everything to lock up.

If the motor is not running or turning over he cannot test compression. I suggest a leak down test to see if your valves are bent. Oh and balance shafts have been known to sieze up too.

 

[WES_393]

Watch the crank pulley while a friend cranks the engine over. If it spins and the cams don't, you having timing belt problems.

 

[2gTurBoD]

Going off what he said above me, also check the position of the cam gear dowel pins.

 

[packrat]

That has gotta be the strangest setup I have ever seen....thanks for the pic!
I will ask around tomorrow, but like literally I have a 1/4 socket set and my spark plug socket is two extensions and a big ass hex key i shoved in the end to get me to this point...I'm thinking the jumping timing theory seems most plausible, due to the condition of the belt that I can see...I was downshifting to slow down for the light, but nothing crazy. (3k rpms-ish).
I will also pop the sparkies to see if the pistons are actually moving too. I am assuming they are moving due to the sounds I am hearing, but I haven't actually seen them move.

A fully snapped belt sounds like whizzing/clanging, just like if the starter was freewheeling the crank/piston assembly and bashing it into things.

This sounds more like it's trying to start, but it's compression is weak(Non-moving cams help this theory). No clanging/banging/weird metal on metal sounds. Almost like...ever tried to start a motor with a blown head gasket btwn cylinder's 2/3 - kinda like that...

Confirmed. Bottom end does spin. Top end doesn't....

 

[packrat]

Turns out there aren't any bent valves! O_O i'm...i'm still in shock...

 

[packrat]

If you sheared the teeth off of the belt at the crank pulley tou would have your symptoms axactly. I would look there.

This is exactly what happend. Due to a cam seal blowing out inside the timing case, it soaked the belt in oil and caused the teeth to take a hike.
Luckily the thing stopped at TDC. didn't smash anything.
All seals and bits have been replaced on that side of the motor.
Shinigami is back in action.
Thanks dudes!
Rat

 

[97gsxIA]

Glad to hear you had no bent valves! I've broken a valve completely off into the cylinder before.. I know I got a picture around here somewhere.......

 

[packrat]

I had all my exhaust valves bent on a ca18de when the timing belt got all screwed up. So I know how rare this is!
I gave my Talon a hug when I got her back!
I'm a sick man...
Rat