Does rod knock get louder with higher revs?

Hi Don - took some photos, not great resolution as bore scope maxed out here
I think my rail is different to yours?
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Is the piece of rail that fits into the tensioner piston hitting or touching the aluminum wall of the timing cover? There should be at least 1-2mm there Is the chain stretched and what you are hearing is the tensioner rail hitting that wall? Had that happen on a 2002, same difference had other issues but ended up putting in a new chain and a much better cam gear

Thanks, Rick
 
I don’t know what to say- do you have a cell phone you can use? I’m simply using an iPhone 11- nothing special. Your pictures are completely out of focus?
Is this an m30 engine? Can you take an in focus pic from a foot away or maybe 2 feet away? Your chain is a complete blur. please don’t take boroscope or close up pics- it’s defeating the purpose. Take an exact copy of the picture I posted from the same distance with a clean lens. Copy the 1st picture I posted exactly. Use a cell phone.
thanks!,!!
 
Are these better?
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It appears to me that the tensioner may be touching the wall on the lower timing cover? Can you check this by using a large screwdriver in the spot I have marked?
The tensioner and tensioner piston should be very stiff and barely move.
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Mine isn’t very stiff at all. But the small arm that slots into the tensioner piston does not touch the wall however hard I try to move away from the piston. from the video the “long side” of the tensioner does hit against the wall when you pull it towards the piston far enough.
I am a bit confused how mine isn’t very stiff - given it’s a brand new OEM spring from BMW. Used the part number from RealOEM. I guess I need to find a stiffer spring?
 
You know, I bought 3 new tensioner pistons awhile ago. I could not get any of them to pump up hard Ended up going back to a good used one that I had, pumped up just fine On these new ones there is a ball with a spring in the center small hole in the groove of the tensioner, I am assuming that oil is forced in past the ball and spring and holds pressure in but I could not get enough oil in behind that ball to ever get the tensioner hard ( now, everyone quit laughing and get your mind out of the gutter )

The old tensioner did not have that spring or ball Is this something new?

If you can't get the tensioner to tighten up, that rail will be banging back and forth as the engine is running and more so on start up and low rpm rather than higher rpm where chain speed is fast enough to compensate for the loose tensioner

Thanks, Rick
 
I found a trick to getting the bleeding going is to loosen the 19mm cap on its threads a little, start pumping with the long screwdriver, when oil starts to pass the threads then tighten the cap and keep going until it’s firmed up. If you shake a clean new piston you should be able to hear the bb rattle inside.
 
In your video, there is way not enough oil in that little well area, fill it right to the top edge of the wall, you may see small bubbles of air as you bleed it The piston has to be completely emerged when you are doing this. Be prepared to add more oil as it gets drawn into the tensioner Right now, all you will get is exactly what is happening, in and out with no effort at all On some of the older tensioner pistons, you could actually hear the oil being sucked in as you pumped it up.

Thanks, Rick
 
Well- that’s quite the movie..

The spring is not the problem. The one you have is fine.

We notice immediately that there is no hydraulic tension in the piston…

Properly bled, I assure you that you would not be able to move the piston 1/8” With your tool.

The other guys have explained clearly that the tensioner piston needs to be bled for it to work and also very clear you have to have oil in the catch basin to bleed the piston.

You need to install your upper timing cover, fill the oil basin at the piston and go back and forth with your screw driver/tool to bleed the piston.

Bright flash light, quart of oil and bleed that piston with eyes right on it to actually see the air bubbles come out. Liston and watch- push in and wait for bubbles to come out. No bubbles, release pressure and repeat. No bubbles ever- you got a problem .
 
Last night I did that. Had same problem with Rick so replaced with old piston which worked better. Primed and piston did become a lot firmer. Started engine and knocking noise still there.
I’m going to dismantle tonight and try again
 
Oil pressure guaranteed?

can you post a pic of top of head showing full position of oiler bar?
 
Grap the yellow plastic guide and verify it does not move.
 
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