Two weeks ago I took the car on a small trip (40 miles each way), after I got off the highway on the way back home I heard this HORRIBLE noise. Scared the crap out of me. Threw the car in the garage and left it. Started it a few days later and it was back to normal. A little while ago I wanted to take the car out for a ride, started normally and ran good, but the second I put it in reverse, I got the noise again. The oil level is good, the oil was changed about a month ago and the filter is brand new as well. Here's a video:

http://s250.photobucket.com/albums/gg253/jbrown122/?action=view¤t=video-2010-09-12-12-55-24.mp4

Please don't say I need a new engine!! ='[!!
--
Jake

The car is in the shop now. So far all I know is that is has no compression in cylinder 3.
A while back, on the highway, it made the SAME noise and ran like it was only on a few cylinders. I let it wait a minute then it was back to normal. Now it's doing the same thing over again.

Why is this?
--
Jake

Hello,


A valve is sticking.


Goatman

Thank you. I think my mechanic is just going to go ahead and do a valve job. I have a spare head w/ valves, if I had more time to trouble shoot I could have done it.
--
Jake

well. the mechanic called and said that the piston basically exploded and the wall got all scraped. so I'm on the hunt for a used engine. ..
--
Jake

Think John Mc is right - it's the fiber timing gear coming apart. Wonder if you put a timing light on it and see if it bounces around. You can replace the gear set without pulling the engine.

Although it can be very difficult to get the hub off the cam shaft without the gear to hold on to.

When the timing gear fell apart on my PV's original B18, it made a HORRIBLE racket. LIke a jackhammer, or maybe like a big diesel engine started up on a cold morning. But it never stopped running, even though the gear was so knackered it fell off as soon as I took the timing cover off.
--
'63 PV544 rat rod, '93 Classic #1141 245 (now w/16V turbo)

well I hope that is all! the lubrication at the top of the engine seems decent and the noise is just about the same with the cover off. tomorrow my mechanic wants to hear the video. so maybe by the end of the week I can have it taken to the shop. I really hope that's the problem!
thank you guys for all the help. I'll keep updating. .
--
Jake

To me that sounds much too "sharp" and regular to be a timing gear breaking up. I'd first check for a stripped tappet adjuster or a broken valve spring. With the valve cover off and plugs out, turn it over by hand and watch the action of the valve gear. You might see that one doesn't work a smoothly as the rest.

I removed the plugs and valve cover and turned the engine, everything seems to be 'smooth' up there
--
Jake

Any true catastrophic engine failure such as a bearing would not be intermittent...

a timing gear separating could be.

--
-Matt I ♥ my ♂

The link doesn't work. I'd guess the character "¤" doesn't belong but don't know what would work.
Can you describe the noise a bit more clearly, and specifically when you hear it and where it comes from?

It is a LOUD, fast paced clicking. It gets faster and louder as the revs increase. Cant tell where in the engine it comes from.

if the link doesn't work try this

http://s250.photobucket.com/albums/gg253/jbrown122/?action=view & current=video-2010-09-12-12-55-24.mp4

(delete the spaces between 'view & current')

kinda sounds like a spun bearing :O
--
Jake

Can't get that one to work either. It takes me to a login screen.
You can't tell whether it is high or low in the engine, left or right, front or back?
Does it get louder if you take of the oil filler cap?

I've taken the liberty of linking your video directly, should get more replies...

That is loud, shouldn't be hard to locate the source.

Good luck!
J.J.

thanks a lot!! I'll definitely locate the noise tomorrow
--
Jake

Nasty sound, for sure, but I'm not thinking it's really a bad rod bearing. It's just not deep and 'clunky' enough for that, sounds a little lighter in tone. When my PV's engine spun a rod bearing the sound was deeper, and also came and went depending on what the motor was doing. Didn't really make any noise at idle unless you pulled the spark plug wire for that cylinder.

First and easiest check, pull off the valve cover and crank the motor over and look for anything unusual. I'm not really holding out much hope for that - the usual failing in the valve train is a flat lobe - and those happen pretty quietly most of the time.

Another possibility - something small and metallic got into a combustion chamber somehow, and now it's hammering away. A quick check might be to pull the spark plugs, if there's anything bouncing around in there the plug will get beaten up some.

My own crystal ball hunch - is that it's the timing gear coming apart. The outer fiber section can come loose from the steel hub, and that allows the gear to rattle against the aluminum timing cover on the front of the engine.


At the very least, you have an incremental way to work toward the problem. Pull the valve cover, look for problems. Pull the plugs, look for problems. Pull the timing cover, look for problems. You could pull the head and look for problems after that, but at that point you're probably going to have to pull the motor anyhow.
--
'63 PV544 rat rod, '93 Classic #1141 245 (now w/16V turbo)

Is it louder with the oil filler open?
Have you run it with the valve cover off?

Its so loud that it sounds like its all over. I can start it up again soon and see if I can tell. I'm pretty sure its a bad bearing however
--
Jake

That sounds like a Ford Model T running without oil.
BEFORE you start it up again, take off the oil filler cap and tell us if you see plenty of lubrication on top immediately after starting it up.
--
My Volvo, now on 6 pages at: http://www.californiaclassix.com/Bernard/PV544-1.html