M30 Oil Distribution Tube

Dick Steinkamp

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I removed the valve cover in my Bavaria today in preparation to adjust the valves and immediately noticed the front hollow hold down bolt for the oil distribution tube was missing...

IMG_5178.jpeg


Luckily I found the bolt and the aluminum sealing washer in one of the cavities in the head.

Although I haven't heard any strange sounds from the engine, what damage could this have caused?

The torque spec for this bolt is only 7-9 ft pounds. It can't be much or it will crush the tube. I plan on putting a drop of blue Loctite on the bolt before installing it. Has anybody else done this?
 

Mot27cars

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Yes. And there are new bolts with pre-applied loctite type material on the new bolts. I have cleaned threads of bolt and hole as well as I could and very sparingly used blue loctite.
 

stphers

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Have a look at the oil holes on the side of the bolt, if these are elongated at all, it means the bolt has been over torqued and should be replaced There is an aluminum sealing washer on both sides of the tube A little loctite won't hurt , you should always check this hen doing a valve adjustmebt, they do come loose

Thanks, Rick
 

sfdon

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There are many approaches To this

Lock tight
Safety wire
Putting a crimp mark on the threads
Installing the factory replacement part that comes with a thread locking compound
You will spot the updated bolt by the circle on the head
 

Dick Steinkamp

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Thanks all.

I'm going to take out the other bolt, install new sealing washers, and Loctite both bolts.

It does not seem like a good thing that the upper end was not oiling the way it should have been. This must not be as critical as I would think.
 

Dick Steinkamp

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Examine your cam lobes for damage including pitting and Presence of a saddle
on the top/side of lobe
I think I dodged a bullet. There doesn't appear to be any pitting, scratches, etc on any cam lobe. No "saddle" that I can see or feel on any lobe. Normal shiny track where the followers ride the cam from the sides of the base circle up and over the lobe.
 

Mot27cars

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Has anyone here crimped the center of this oil tube as I’ve heard done before to increase oil flow to #1 and #6 lobes?
 

deQuincey

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Thanks all.

I'm going to take out the other bolt, install new sealing washers, and Loctite both bolts.

It does not seem like a good thing that the upper end was not oiling the way it should have been. This must not be as critical as I would think.

i would prefer safety wire over the loctite route
it is very easy to drill a hole in the hexagonal head and then place a wire
once you put the loctite you never know where it might end
comercial bolts have solid loctite
 
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