Thread: 300TDi knock noise

I fiddled with a TDI that was at best guess 3 teeth off on timing once
Ran like **** buy pump was retarded relative to crank
It wasn’t noisy

I know that doesn’t help

Bad news that it isn’t vacuum

Only other easy one on the right of block is to remove the lift pump (don’t disconnect lines it will run ok for a bit)

But honesty we need JC to listen to your video
I’ll text him

S

Originally Posted by roverrescue

I fiddled with a TDI that was at best guess 3 teeth off on timing once
Ran like **** buy pump was retarded relative to crank
It wasn’t noisy

I know that doesn’t help

Bad news that it isn’t vacuum

Only other easy one on the right of block is to remove the lift pump (don’t disconnect lines it will run ok for a bit)

But honesty we need JC to listen to your video
I’ll text him

S

Thanks! Yeah i really need someone who has listened to lots more 300Tdi's than me to have a listen. If i lived in Perth i would run it down to Rovertech as i have heard the guy there is pretty good.
I am only going off memory that my other 300Tdi didn't make that higher pitched knock as well.

I flicked the link to JC
His feeling was too much advance or cam out of time

You mention 1.6mm Of lift at the IP so might need to check cam timing

JC mentioned he had a 300tdi that the cam was out enough to let piston kiss the valves and it was still banging along

S

Originally Posted by roverrescue

I flicked the link to JC
His feeling was too much advance or cam out of time

You mention 1.6mm Of lift at the IP so might need to check cam timing

JC mentioned he had a 300tdi that the cam was out enough to let piston kiss the valves and it was still banging along

S

Thanks
I will pull the timing cover and check the cam pulley is still timed spot on. Also, a good chance to re-check the harmonic balancer crank key.

Had a knocking noise from my hyundai engine last year. Thought it sounded like bearing or piston. Turned out to be the power steering pump. Car had 200,000 km on it, and from the number of pumps on ebay, it was a common problem.

Originally Posted by roverrescue

I flicked the link to JC
His feeling was too much advance or cam out of time

You mention 1.6mm Of lift at the IP so might need to check cam timing

JC mentioned he had a 300tdi that the cam was out enough to let piston kiss the valves and it was still banging along

S

After work today i pulled the harmonic balancer - was still nice and tight.
Pulled the timing cover and checked the cam timing it is still spot on.
I then put the balancer back on and ran the engine without the cover - just to check that the noise wasn't a loose cam/FIP pulley or something behind the timing cover and found that the noise is not coming from behind there.
So then i pulled the rocker shaft to check the bolts/studs and they seem fine. I looked down the pushrod holes and the lifters look ok (no smashed cups/edges).

However the noise sounds like it is coming out the side of the block (front right-hand side) exactly where the follower assemblies are inside. And when i lift and drop the lifter up and down on the 'penny' it seems to make the same noise that i am trying to find!!

Maybe its just a coincidence... What are the troubleshooting steps to rule out the followers? Why would a follower make that sort of noise? I obviously checked the valve clearances and they were ok - so how would the follower have enough 'play' to make a knock like that? I put a long skinny screwdriver down the pushrod hole and checked for horizontal play but still looks ok.

The only thing I can think of is a chunk out of a cam lobe
So with tappet adjusted there is follower pressure on the lobe but then when it rotates around there is a step or jump.

BUT

To get to that your at stripped down engine level diagnosis.

Can I commend you on your chase - you must be fully frustrated and needing a beer or seven !

Thinking back to the video it could be a single cam lobe issue - timing at idle seems about right. How bad would it be to run with the rocker cover off- probably messy but you might see some shimmy or kick at the offending tappet??? Would at least confirm noise is between cam and pushrod????

Steve

Just for a giggle,
with the engine idling crack off each injector pipe at the injector and see if the noise largely disappears, obviously do it up before moving to the next!

Cheers
James