Zero compression on all 4 cylinders....I opened head and....?

My guess is a lot of bent valves. Borrow a cylinder leak down tester and listen to where the air is going. Hell with zero compresson you might even be able to steal the hose from your compression gauge and blow air into the cylinders using a blow gun and hear where the air is going? Not too many choices of where it can go.

 

zero compression would mean seriously bend or even broken valvedisks. In the first case your valveclearance would be far beyond the normal reading. you could check this.
in the second case the valveclearance would be 0. You could check this too.

However i cannot image these both scenario's can occur with your timing in proper shape.
I do think your first asumption (that the compression IS zero) is wrong.


edit, of course 0 compression could also be caused by big holes in all of your pistons. However this seem highly unlikely (esspecially since the other bank is doing oke)

 

Unless by a freak coincidence the timing belt spun 1 full revolution around cam gear when the resistance of valves smacking pistons was encountered.

 

I guess the chanches of winning the lottery are much bigger than this to happen

 

first, keep in mind:

for every two rotatons of the flywheel, the camshaft will turn only once.

so the change that you have your alingment oke by looking at the marks of only one bank (can't see clear rm the pictures, maybe 'm wrong)are only 50%. to make sure your timing is oke you must look at all camshaft-alingment marks.

ps this will result in bending all stuff

 

Have you ever had the car running right?

Could be the previous owner broke a timing belt the lapped a new one on and sold you the car?

The car will run and drive on 4 cyl, it’s just slower than it should be. You are saying the car wouldn’t start with the front bank 1 tooth off……but it would have if the rear bank was working at that time. The good news is you can pull the rear head and have a look without pulling the engine.

 

Maybe your compression test gauge broke. Perhaps try a different one or try it on the other bank?

Aaron

 

+1 on the leakdown. Since you have everything supposedly at TDC, hook a leakdown kit up on #1 and listen where the air comes out. Its either going come out the intake, the exhaust or back up the oil drainbacks. Possibly some combination of the 3. You could just set the cover back on an listen/feel at the oil fill hole.

Also, since the cam cover is off, spin the motor by hand. DO the cams move? Do the thimbles follow the cam or do all/some of the valves just stay open? If that goes smooth, spin it with the starter and watch again. See if you have valves staying open - Sticking.

The good news is that from your pics, you are correctly oriented and the #1 lobe sets look to be in good condition and there are puddles of oil at the thimbles.

Rick

 

did you check valveclearance?

 

So you've never had the engine running propperly right?

The cams are clearly in the correct locations and are turning right?


If **** ain't broke inside you have compression but you don't have compression.....becasue you have bent valves and dinged pistons inside the rear bank.

 

I broke a cam belt on the front bank on a 2v engine while the car was running . I reset the timming markes put a new belt on and crossed my fingers as it started up. That was around 4-6k miles ago and the car has been fine and uses no oil or water or missfires . I havnt done a compreshion test but from driving it all seems to be well.

The main repair guy told me they dont always hit but that I was lucky no damages seems to have been done.
marc

 

If the valves are bent you would not see it in the valve clearance if whoever replaced the timing belt adjusted the valves.

It's time to pull the engine and rebuild it I'm afraid.

 

Bingo!

 

If the valve is bent, it can't close all the way and the valve clearances would be over spec....if know one touch it.

If the valve are broken that valve clearnces would be zero

 

It could be that the Valves are being held open by the wrong shims. Just make sure that the Cam is not pressing down on the lifter. Can't the cam be removed and the lifters removed to see valve stems... and maybe check them all for symmetry. I would think if one or more valves were bent then the stems would be recessed.

You could check this as a last resort before head removal.

 

Not sure you could get shims thick enough to compensate for valves that are bent badly enough to produce 0 compression particularly if a belt went in the past. Ive seen plenty of DOHC 4cylinders same setup as a 308 with a bucket and shim and there is a good .250" clearance between the base circle and bucket. My approach would be to roll the engine over looking for that clearance to know ahead of time what exactly is wrong purely from a diagnostic standpoint as its what customers pay me to do rather than say "i dont know" , but in the end, it has to come out whether you diag it further or not.

 

now two man are telling it to you, please check

 

I like the idea of putting the engine at TDC on #1 & pumping air into spark plug hole. Should tell the whole story.
Bill

 

This question sort of relates to the OP, has me thinking anyway....

Would you feel or here interference between the pistons and valves, if you turn the engine by hand (I mean turn it using a socket, and not by starting the car)?

As a matter of procedure when I change the cam seals, etc. and line up all the timing marks, install new belts and then get ready to close up, I spin the motor clockwise maybe 12-16 times, not fast but not too slow, and just listen. I always figured if something was setup incorrectly I'd here it or feel it.

Also, sometimes when putting a new belt on, and then turning the motor, it's not uncommon for the belt will slip a tooth on the drive or cam sprocket if not aligned perfectly, and you then need to start over again. Safer to find out by turning by hand then by starting the car. Just go back to PM1-4, line up the cam marks and start again.

Am I off base here?
Phil