7mgte Top End Ticking Rattle?

[jayybrue]

https://www.youtube.com/watch?v=jIBMBDC541M

Ignore all the zip ties and other things wrong lol it's just temporary as I
figure this out. It's on a MAFT pro so boost leaks wont really affect the noise)

I've recently put together this 7m after it sat for about a year. The head was off of it to replace a head gasket that had not blown (preventative maintainance). I picked it up from my friend who owned it before and hes the one that took the head off.

Before the head was removed it ran fine with no noise.

Oil pressure is around 6 at idle

The strangest thing about the noise is that it does not start happening until the car warms up. After about 3 minutes of running at idle, the noise starts. The oil was changed twice before I ran it just to ensure it was clean. There was never water in it.

Everything in the valve train looks fine as far as I can tell. All the retainers are in and all the cam lobes are fine. Nothing has fallen into that area either. I've just re-shimmed the valves so they are in spec.

I'm lost here gang.. let me know what you think.

[jayybrue]

https://www.youtube.com/watch?v=07iHH5KIjOE

https://www.youtube.com/watch?v=aaFV4qYif-Q


The noise is not there as you can tell in the first video. That was taken right after start up in about 45° weather. This was the first time it had started after the ecu was reset (hence the high idle). Also the exhaust manifold has several leaks which cause that generally gross but quiet ticking in the background

The second video was taken about 5 minutes after the first, and the noise had come back at that point. The engine was warm now and idle was closer to normal.

I listened all over the engine using a long extension, and could hear the best on the top of the middle of the head where I point in the second video. I listened to the injectors and they were perfectly normal. I took each of the spark plug wires out and the noise persisted (although slightly different as idle fluctuated). I also properly torqued the cam gears but it made no difference.


Also the compression was tested twice and it is fine. This rules out a bent valve or anything of the sort.

[interested!]

Originally Posted by jayybrue

https://www.youtube.com/watch?v=jIBMBDC541M

Ignore all the zip ties and other things wrong lol it's just temporary as I
figure this out. It's on a MAFT pro so boost leaks wont really affect the noise)

I've recently put together this 7m after it sat for about a year. The head was off of it to replace a head gasket that had not blown (preventative maintainance). I picked it up from my friend who owned it before and hes the one that took the head off.

Before the head was removed it ran fine with no noise.

Oil pressure is around 6 at idle

The strangest thing about the noise is that it does not start happening until the car warms up. After about 3 minutes of running at idle, the noise starts. The oil was changed twice before I ran it just to ensure it was clean. There was never water in it.

Everything in the valve train looks fine as far as I can tell. All the retainers are in and all the cam lobes are fine. Nothing has fallen into that area either. I've just re-shimmed the valves so they are in spec.

I'm lost here gang.. let me know what you think.

Hi , Reading your thread reminded me of a problem I had with a NEW CAR . The engine would " tap " at tickover and sounded for all the world that the push rod tappets were not to spec ,but run smoothly even though it was serviced under warranty and I was still running it in , the tightest engine I have ever owned . After complaining several times at every service the tappets were adjusted and everything double checked , the problem was found to be PISTON SLAP ! . One of the pistons was undersize by enough to make the piston " Rock " at TDC and BDC , only noticeable at tickover ,which would be a problem with high mileage engines . Remedy was to rebore , which cured the problem while still under warranty . It meant I had a lot of running in before the engine was " free " . Hope this helps you find your problem .If , while the head was off , the carbon was removed from the cylinder bore at TDC , the piston is now free to "Rock " , which is why it makes a noise now .

[jayybrue]

What do you mean by "tickover"? The thing about piston slap is that it gets less intense as the engine warms up. That is the opposite of what's happening in this case.

[interested!]

Originally Posted by jayybrue

What do you mean by "tickover"? The thing about piston slap is that it gets less intense as the engine warms up. That is the opposite of what's happening in this case.

Tiickover is a UK term used instead of idle .