PewterC5-2000

All,

For starters....I'm feeling pretty low right now.

Hopefully those of you that worked your way through abnormal ticking noises can help me figure this one out. I've read tons of related threads but I haven't found anything that seems to be exactly the same. For what its worth you can see the mods for this daily driver in my sig below. The car has ~50K on it of which maybe 20K is on the heads/cam setup.

On the way home today I make a shift from 4th to 3rd with the rev's hitting maybe 3K once in 3rd. Immediately I hear an obvious ticking (wouldn't describe it as a thunk but more like a click or tick) noise doesn't sound normal. At first I'm thinking that I just broke a spring (thank goodness for the MTI dual springs).

Anyhow, after getting the car home here is what I know:

1. Removed all rockers and pushrods; no visible issues like rod end problems or rocker play or bearing issues. Push rods are straight as I can tell as I rolled them on a granite countertop (i.e very flat surface)
2. From what I can tell after looking at them forever I don't see any broken springs although I can't see the inner springs in the dual setup.
3. I'm not sure where the noise is coming from but it sounds like its possibly the top of the engine.
4. The noise seems to come and go at idle (which is odd) but its always there above ~2.5K and it increases in sound level with RPM.
5. The ticking at idle is about 2 ticks/sec....so.....
If my math is correct (may not be as I'm dazed at the moment) a given cylinder is at TDC at approx 700(rev/min)*(min/60sec)=11.7 times (revs) per second.
A given cylinder fires at 11.7(revs/sec)*(.5fires/rev) = 5.8 fires/sec so wouldn't this mean that valve or lifter noise would be at approximately (1/5.8=.17 sec per fire)? I'm sure I've screwed up my math here.....anyhow, the 2 ticks/sec don't seem to add up for a valve train issue although I'm no expert in this area. I was guessing at the 2 ticks/sec....I don't think I'd be off as far as .5 compared to ~.2.

6. The car doesn't seem to be running rough or misfiring.

Tomorrow I plan on checking the plugs and the plug wires as well as the oil (hopefully I won't find any debris).

My gut tells me this is a lifter problem but then again I've never had to go down this path.

Does this sound anything like a header leak? It doesn't to me who knows at this point.

Any thoughts or experience with these same symptoms?

TIA,

Richard
Austin Texas

2000 C5 Hardtop Daily Driver (50K total....~20K on the heads/cam)
MTI 2E Heads, Stealth-I cam, kooks headers, MTI pushrods etc.

mcamp001

iTrader: (1)

same thing mine did, lifter broke and destroyed the motor with metal shavings. Drain the oil and check the drain plug for metal

PewterC5-2000

Thanks for the input. How did you determine that it destroyed the engine? Did you have to disassemble the entire bottom end?

vettenuts

iTrader: (4)

Depending on which one is ticking, you can pull the intake/valley cover and see some of them but not all. I would start with the easy to reach stuff first, like valve springs. 20K on a performance set of springs and aftermarket cam are about due for a change.

PewterC5-2000

Arrgghh,

Here is what I've found. Anyone seen damage like this and know what the culprit was?

http://rides.webshots.com/album/550898473ULtfFl



Richard
Austin Texas

2000 C5 Hardtop Daily Driver (50K total....~20K on the heads/cam)
MTI 2E Heads, Stealth-I cam, kooks headers, MTI pushrods etc.

1stz06

iTrader: (18)

That doesn't look pretty!!! Sorry I have no helpful advise but I am curious as well.

J.R.

PewterC5-2000

All,

Here are some pics of the carnage.

I pulled the cam out and as you can see its toast as expected.

Additionally, I found some fairly nasty shavings (that are not ferous/magnetic) in the oil filter. I'm no expert but I'm assuming the shavings are bearing material.

Pics are located here: http://rides.webshots.com/album/550898473ULtfFl

So, the question is what shortblock to buy now?

Richard