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Discussion Starter #1
Curious as to the function of part no. 6 in the diagram below from RealOEM. Appears to reside inside the hollow core of the camshafts.

--Peter
 

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Discussion Starter #2
Found it!

When the VANOS setting is adjusted by the
high-pressure circuit, the lubricating oil in the
camshaft is therefore potentially a hindrance
to themovement of the piston. To prevent that
happening, there is a pressure relief valve with
an opening pressure of 4.5 bar fitted in the
camshaft. That pressure relief valve opens at
an oil pressure of 4.5 bar and allows the oil to
escape into the rear section of the camshaft.
The camshaft has an open end aswell as open
inspection holes. Thus the oil can return to the
oil circulation system"

--Peter
 

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Discussion Starter #3
Why My First Bavarian Disaster Engine Blew Up

Finally figured out why I think my first Bavarian Disaster motor blew up. It used the custom made camshafts I currently have bolted in the engine. Those camshafts lack the oil relief valve that is the subject of this thread. Not sure whether I will be able to install the valves in the custom cams. If not, my options are to run vanos-less or to swap out the cams and solid lifters.

--Peter
 

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Discussion Starter #4
This is what they look like. Extracted them from a set of stock cams I had lying around. Trying to see if they fit into my custom cams now.

--Peter
 

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Discussion Starter #5
They fit perfectly in the custom cams. The cams just never had pressure relief valve installed in them. Four years later, I finally figure it out.
To install these pups, I'm having to disassemble most of what I assembled over Thanksgiving, but I am delighted to do it, now that I finally have diagnosed and corrected what went wrong with the first Bavarian Disaster motor. It is an engine building mistake that I will NEVER make.

Lesson to others: when installing new cams in an S62 destined to be used with vanos, particularly custom billet cams, make sure that oil pressure relief valves are installed inside the cams.

--Peter
 

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Discussion Starter #7
It is now my belief that the bank 1 vanos on that engine failed and "stuck" in an out of range position because the custom made billet cams did not have these valves installed in them.
 

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Discussion Starter #9 (Edited)
That was the second engine's problem--piston material and piston to wall clearance not matched to the liner material. I'm talking here about why the first engine blew up with the vanos.
 

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Sounds like some quality work was done.

Glad you sorted it out.
 

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That was the second engine's problem--piston material and piston to walk clearance not matched to the liner material. I'm talking here about why the first engine blew up with the vanos.
So the second engine didn't have the cams? I've lost count of how many engines you've ruined on jack stands.
 

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Discussion Starter #13
@tradin1:

Both were in the car, Sparky. I need to ensure your new colleagues at GM know your nickname.

The cams were in both engines, but the second was vanos delete with timed cams, so the lack of pressure relief valves made no difference, Sparky.

--Peter
 

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@tradin1:

Both were in the car, Sparky. I need to ensure your new colleagues at GM know your nickname.

The cams were in both engines, but the second was vanos delete with timed cams, so the lack of pressure relief valves made no difference, Sparky.

--Peter
I see, thanks for clearing that up.

-R
 

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thanks peter i just checked my schrick cams that just came in, i was waiting for these for a few months now just to make room in the shop to pull my engine and get it on a stand lol
 

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Hey Peter, I see you said you believe you found the problem with your first engine vanos failing, because of this pressure release valve. What exactly happened and what kind of damage did it cause because of this?? Reason I'm asking is I installed custom reground cams in mine which I dropped off at FS tuning about a month ago. I never knew about these relief valves and now its making me worry if the cams don't have them installed.
 

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Discussion Starter #17
Hey Peter, I see you said you believe you found the problem with your first engine vanos failing, because of this pressure release valve. What exactly happened and what kind of damage did it cause because of this?? Reason I'm asking is I installed custom reground cams in mine which I dropped off at FS tuning about a month ago. I never knew about these relief valves and now its making me worry if the cams don't have them installed.
The engine experienced catastrophic failure, with pistons hitting valves and cracking the heads and block. Was a near total loss.

You are very wise to check! In fact, that is the principal purpose of this thread now, viz., to ensure that no one else makes this mistake. I did not know about these relief valves, and I think very few engine builders do because the stock cams already have them installed. I suspect Schricks come with them already installed as well. So builders don't think about them, especially since they are unique to early vanos systems such as the S62. Dusty Renteria, formerly Dinan's master engine builder, knew about them right away and instructed me on how to remove and replace them. What a Godsend Dusty is. I am sure Raikku knows about them as well!

--Peter
 

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Discussion Starter #18
thanks peter i just checked my schrick cams that just came in, i was waiting for these for a few months now just to make room in the shop to pull my engine and get it on a stand lol
Good move, George. Assume the valves came already installed in the cams?

--Peter
 

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I wonder if the reground cams found for sale even had them removed in the first place?
 

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Discussion Starter #20 (Edited)
I wonder if the reground cams found for sale even had them removed in the first place?
Just to be clear: My cams are not regrinds. They were custom made on a CNC machine from solid billet with special ramps to accommodate solid lifters. That is why my situation may be relatively unique: Most custom cams are just regrinds of the factory shafts and so likely have the valves installed in them from the get go and are not removed during the regrinding process.

--Peter
 
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