S54 Vanos post Beisan/DV Rebuild Timing Issue

[Arinb12]

Btw, Neither 60 deg and 0 deg are the correct absolute working cam angles. Their working range are: IN [70: 130] after TDC and EX [-83 : -128] before TDC.

Are you saying my mechanical timing is 10° off? Because it's stating 60° while 70 is the minimum range starting point?

[Arinb12]

From that one sample of command to move EX to max advanced position (zero deg is max advanced and 45 deg is max retarded), 5 deg adaptation makes no sense, and so I think the test had performed moving at a few positions and then averaged out the error to a value of 5. You only posted one sample data and so we haven't seen the other values, I think.

That screenshot (diagnosis) is the vanos adaptation values from a different place in DIS. The test I did stopped after showing me the following intake values, it did not get as far as the exhaust values.

I am not sure if it is saying it failed on the inlet or the exhaust being out of range (photo below)

[Arinb12]

DIS did not show me anything more than that

One thing I did notice was that the exhaust piston was easy to slide in and out, could slide down jsut by turning the vanos on its end. While the intake piston was a little more resistant (better seal?)

Maybe the exhaust side did not seal well with my replacement piston from another vanos because the inside seal was already worn to the original piston size? Perhaps this is causing my issue with the advance/retard part of exhaust test?

It can't be the actual timing if my pin slides in and bridge is flat when at TDC right? (It's easy butter slide for exhaust, and little resistant to slide but still slides easily enough for intake)

I couldn't have done anything wrong when using a solid tensioner? Maybe too much or too little tension did something?

[sapote]

What do you mean regarding the EX? It's not commanding it to move?

From that one sample of command to move EX to max advanced position (zero deg is max advanced and 45 deg is max retarded), 5 deg adaptation makes no sense, and so I think the test had performed moving at a few positions and then averaged out the error to a value of 5. You only posted one sample data and so we haven't seen the other values, I think.

[sapote]

I think the tool commanded to move the vanos end to end, and the posted pic is only one sample out of a few target positions. And from averaging many samples, the DME chose to use that adaptation data.
The values in the pic of 60 and 0 are relative angles, with 60 as the max retarded and zero is the max advance for Intake (130 -70 = 60) . For exhaust, they should be 45 and zero (-128 – (-83) = 45)

Take a video and maybe we can interpret it better.

[Arinb12]

The tool display doesn't make sense to me either.
Consider the DME commanded Intake to 60* and the actual was 59.8* with error only 0.2*, so why it needed to adapt a whole -1 deg?

For EX, command is 0 and actual is 0.5, and the adaptation is 5 deg.

Btw, Neither 60 deg and 0 deg are the correct absolute working cam angles. Their working range are: IN [70: 130] after TDC and EX [-83 : -128] before TDC.

What do you mean regarding the EX? It's not commanding it to move?

[sapote]

Exhaust 5.0 adaptation?!
Inlet shows -1.0 (makes sense as pin didn't slide in easy but bridge did lay flat)

The tool display doesn't make sense to me either.
Consider the DME commanded Intake to 60* and the actual was 59.8* with error only 0.2*, so why it needed to adapt a whole -1 deg?

For EX, command is 0 and actual is 0.5, and the adaptation is 5 deg.

Btw, Neither 60 deg and 0 deg are the correct absolute working cam angles. Their working range are: IN [70: 130] after TDC and EX [-83 : -128] before TDC.

[Arinb12]

The solid tensioner is to take out any slack on the pulling side of the chain (RH side vu from front).
I would do these steps:
Loosen vanos solenoid block to release oil pressure.
With stock tensioner, turn crank to 3mm before TDC compression (stop crank at 3mm on the left of TDC ref mark).
install solid tensioner just snug. Don't tighten too tight as it pushes hard on the guide and can break it. Slowly turn crank CW to TDC (3mm more than before). Snug up tensioner if it's loosen after turning crank CW. Set cams to retarded and verify with the bridge pin.

At this point the chain should have no slack. Proceed to pretension the hubs and finish the remained steps.
After the hubs bolts are torqued to spec, install the stock tension, then rotate the crank 4 turns and check timing with bridge pin.

Okay so someone help me understand what the hell is going on!

Situation.

New/2nd hand vanos. (Used exhaust piston from my old vanos as this ones piston was missing a seal)
Vanos pressure tests confirm hot engine pressure of 115 bar.
Leakdown fast, accumulator still bad.

Engine timed as per using the solid tensioner and standard preload method.

Engine turned over 10 times post vanos install. Checked at TDC.

Exhaust, bridge flat, pin slides in like butter.
Inlet, bridge flat, pin needs some pressure to slide in.

Ecuworx tool shows (photo):




Exhaust 5.0 adaptation?!
Inlet shows -1.0 (makes sense as pin didn't slide in easy but bridge did lay flat)


DIS shows (photo) the same adaptations.



Vanos test FAILS?! - WHAT THE HELL IS GOING ON?! (photo)








image widget

[sapote]

Here is after the first rebuild



And next the ISTA+ testing values

Questions and comments:
Why the test only commanded the vanos to move Intake to 130 deg (max retarded which is an easy motion) and not to 70 deg (max advanced which is a more difficult motion)? And, for the Ex cam, why commanded to to to max advanced (128 deg) instead of max retarded (83 deg)?

ISTA test value:
For exhaust cam: The actual steering advanced is 128, which is perfect. But the actual steering retarded is 79, which is not too good when the command value is 83 I assume. So 4 deg off here.
For intake cam: 70 deg advanced and 130 retarded and so they are perfect with zero error.

[Arinb12]

This sounds like a lot of works to use the solid tensioner. I would just cheat the crank a little by setting it at 2 or 3mm BEFORE TDC compression, then set the cams timing with the bridge pin, and finish the rest using the normal procedure. Cheating the crank will compensate for the chain slack that normally caused the cams timing to be a little off (bridge foot lifts off on the head intake side.

I managed to find the right size socket to use today so I'm going to try this first. I like to learn and try new methods

[sapote]

This sounds like a lot of works to use the solid tensioner. I would just cheat the crank a little by setting it at 2 or 3mm BEFORE TDC compression, then set the cams timing with the bridge pin, and finish the rest using the normal procedure. Cheating the crank will compensate for the chain slack that normally caused the cams timing to be a little off (bridge foot lifts off on the head intake side.

[sapote]

Does this assume my current starting point is vanos off and hub bolts loosened?

No, you don't want to turn the crank around with the hub bolts loosened. The hub bolts loosening starts when you ready to set the cams timing with the bridge pin.

[Arinb12]

The solid tensioner is to take out any slack on the pulling side of the chain (RH side vu from front).
I would do these steps:
Loosen vanos solenoid block to release oil pressure.
With stock tensioner, turn crank to 3mm before TDC compression (stop crank at 3mm on the left of TDC ref mark).
install solid tensioner just snug. Don't tighten too tight as it pushes hard on the guide and can break it. Slowly turn crank CW to TDC (3mm more than before). Snug up tensioner if it's loosen after turning crank CW. Set cams to retarded and verify with the bridge pin.

At this point the chain should have no slack. Proceed to pretension the hubs and finish the remained steps.
After the hubs bolts are torqued to spec, install the stock tension, then rotate the crank 4 turns and check timing with bridge pin.

Does this assume my current starting point is vanos off and hub bolts loosened?

[Arinb12]

The solid tensioner is to take out any slack on the pulling side of the chain (RH side vu from front).
I would do these steps:
Loosen vanos solenoid block to release oil pressure.
With stock tensioner, turn crank to 3mm before TDC compression (stop crank at 3mm on the left of TDC ref mark).
install solid tensioner just snug. Don't tighten too tight as it pushes hard on the guide and can break it. Slowly turn crank CW to TDC (3mm more than before). Snug up tensioner if it's loosen after turning crank CW. Set cams to retarded and verify with the bridge pin.

At this point the chain should have no slack. Proceed to pretension the hubs and finish the remained steps.
After the hubs bolts are torqued to spec, install the stock tension, then rotate the crank 4 turns and check timing with bridge pin.

Thank you very much, I will try this today and report back.

I had my timing on point with the inlet, the exhaust was just on the boundary. But I've had to put in a new vanos so thought I'd do the exhaust timing again. Ended up accidentally loosening the inlet hub (wasn't thinking properly!) And now I'm having a hard time getting it timed well again on my 6th try already!

[sapote]

Could you give me the steps to use the solid chain tensioner you recommend?

The solid tensioner is to take out any slack on the pulling side of the chain (RH side vu from front).
I would do these steps:
Loosen vanos solenoid block to release oil pressure.
With stock tensioner, turn crank to 3mm before TDC compression (stop crank at 3mm on the left of TDC ref mark).
install solid tensioner just snug. Don't tighten too tight as it pushes hard on the guide and can break it. Slowly turn crank CW to TDC (3mm more than before). Snug up tensioner if it's loosen after turning crank CW. Set cams to retarded and verify with the bridge pin.

At this point the chain should have no slack. Proceed to pretension the hubs and finish the remained steps.
After the hubs bolts are torqued to spec, install the stock tension, then rotate the crank 4 turns and check timing with bridge pin.