Sudden Knocking Noise And Loss Of Power

[asdf205 0]

Today i just topped up my oil and headed out for a few mile drive around the block. Halfway round i felt a sudden loss of power and heard a knocking noise coming from the engine. I pulled over at the side of the road to take a look at there was a distinct noise coming from under the rocker cover. I took it easy on the way home. Spoke to one of my mechanic mates (hes pretty useless) and he said it could be that the timing belt skipped a tooth and its the pistons hitting the valves. Any truth in this?

 

Managed to get a short video

 

http://www.youtube.com/watch?v=UJA4B03yX1w...feature=channel

[SurGie 54]

Yes it could well be but it also sounded like one or more of the main bearing have spun. Take of the cam cover and have a look, they usually have a pen/paint line on the belt and the belt surrounding, turn the engine by hand to see if they are in line.

[asdf205 0]

Ill check the timing tomorow in the daylight. If it was one of the bearings wouldnt the sound come lower down in the block? This sound is definatley coming from the top end.

[Dazza 4]

Oh crickey !

 

That sounds like its on 3 cylinders to me and you would be best to compression test it first, sounds like a valve or timing to me.

 

You havent dropped anything down the oil filler neck have you like a little bit of latex glove ? quite a common thing.

[u47sb2 27 2 Cars]

That sounds exactly the same as the noise I briefly heard when my oil pump died (caused by rock hitting sump guard pushing it into sump pan and knackering the pump).

[asdf205 0]

I had a closer look and there seems to be a bit of oil seeping out of one of the rocker cover bolts which i havent seen before. Im going to take the cover off now and look at the timing.

[asdf205 0]

I decided to start the engine and it sounded fine. I let it tick over for about 5 mins with no problems atall. I then thought the problem might have gone so i took it up the road and it was fine. I changed at about 2k and no problems. Turned around and headed back and as soon as the rev counter hit 3k the noise came back. Its now back on tickover too. Surley if the timing was out and the pistons were hitting the valves this noise would of still been there when i started it up?

[large 33]

It may be too late bit I would check the crank bolt. As the oil pump is a friction grip (no key) and is reliant on the bolt being TAF.