Ticking noise
 

After rebuilding the top end of my 3.3 (rings + head work) there is a distinct ticking sound coming from around the center rear(away from the fan) of the engine.

The ticking sound becomes noticeable after the engine warms up and seems to be about 1 every 2 engine revolutions.

I can hear it even when driving the vehicle.

I pulled the engine and re-adjusted the valve clearances accurately using a dial guage. The noise is still there. I also did a cold leakdown with the engine removed and the numbers were good (4%-6%).

Can anyone give me an idea on the steps to track this down?


Steve

Do you have a stethoscope, with the long tip on it for pinpointing the noise? narrowing the area down can really help.

I had a noise like this that turned out to be a broken valve spring, though it sounded to me like a poorly adjusted valve. No telling yet whether yours is the same problem though, probably not likely.

Keep in mind exhaust leaks will generate a ticking sound that you would swear is mechanical noise.

I agree with WERK I :

Once I also had a "ticking" noise...
After some research the exhaustmanifold - head connection was leaking... And no, it wasn't noticable by traces of carbon etc.
This was also after the rebuild...

Other "ticking noise" I once had: One of the so called "elephant feet" (valve adjustment screw) was worn out. Yes, you can set your valves properly but once the engine is warmed up the worn out elephant feet will start ticking...

Good luck!

Dick

911SC cab

Great info guys. I am back home in Australia at the end of the week and I'll check all three suggestions and let you know.



Steve

I had this for a few years and then finally did the top end. Turned out to be very worn valve guide. Hard to believe this is the cause for you since if the valve stem to guide was loose enough to make an obvious noise it would not measure or feel during the re-install, but I guess stranger things have happened. What I had was a definate tick tick sound, I thought it might be exhaust leak...then pulled the exhaust to look and $$$$ later had a rebuilt top end and lots of other stuff...clutch/etc.

My bet is on the exhaust leak as well. One of those cost me hour to hunt down. Just didn't really believe that that could have been it till I ruled everything else out....sometimes I like to learn the hard way!
Nabil