DIY: Fix your lose VANOS bolts! LOTS O' PICS!

king-rb · Thu, Jun-17-2010, 11:53:44 PM

Top notch DIY, without a doubt!

Quick question that I am not grasping at the moment. What is actually causing the bolts to be "cut" in the middle of the threads? I understand that when they are loose there is play, but what is actually cutting them??

excessive · Fri, Jun-18-2010, 01:07:28 AM

Quote:

Originally Posted by king-rb

Top notch DIY, without a doubt!

Quick question that I am not grasping at the moment. What is actually causing the bolts to be "cut" in the middle of the threads? I understand that when they are loose there is play, but what is actually cutting them??

Its kind of hard to explain, but the loose bolts are the ones that bolt the cam gear (timing chain) to the camshaft. The bolts are worked loose, but cannot fully come loose because of the VANOS adjustment gear and spring that are bolted over top of them. So they are in a loose state, and the timing chain cam gear is moving back and forth ever so slightly on them. This movement is what I imagine causes the "sawwing" effect. Over time, I guess they get sawed completely through, or else they get weak enough to just break.

m3e46freak · Fri, Jun-18-2010, 01:13:08 AM

Great write up ...but good lord that is a struggle.

JRM3 · Fri, Jun-18-2010, 03:14:51 AM

20. Take a break. You need a lot of patience to get the VANOS unit back on. Had your break? Good, proceed... With the
vanos unit in one hand. and your two wrenches ( 7mm and 10mm) in the other, simultaneously align the Vanos unit and
tighten up the two mating shafts on the intake and exhaust sides. I have no pictures of this, because I only have 2
hands. It will take a few tries to get this done. It spent probably an hour getting this part done. Make sure the
markes you made previously line up. OH - and don't forget to replace the VANOS gasket that goes between the unit and
the engine. It would have been really helpful to have a helper at this point. But I'm a lone warrior, and I got it done
alone.

In your statement above, can you expand on the line up you are speaking about. I'm not sure I understand....

casper3t · Fri, Jun-18-2010, 03:30:40 AM

that it? you just take off the vanos and reinstall without recalibrating it? the bmw tech lied to me that it need to be recalibrated with air tools and they wanted to charge me 1500 to replace the vanos gasket.

Highpower11 · Fri, Jun-18-2010, 02:36:14 PM

After reviewing this thread and the OP's original thread shown here... http://www.m3forum.net/m3forum/showthread.php?t=319590

Just a thought... but if the bolts are determined to be secure and not loose per the above thread, is it possible to stake the rear of the cam bolts to their respective housing? We can get to the back of the bolts fairly easily and thus could be done quite easily I assume as a preventive measure, before they loosen, without having to disassemble the vanos unit.

Perhaps a tech can chime in here or even a M.E. If this were possible and successful, it would surely make life a lot easier for those that have not yet had their bolts begin to back-out.

tjpatte · Fri, Jun-18-2010, 03:50:12 PM

Not too sure you would want to put a lateral shock load on the camshafts like that?

Tom

jetmech · Fri, Jun-18-2010, 04:05:46 PM

Thanks to the OP for this writeup. I just had my valve cover off to do the valve clearance check so the "Mini DIY" (see post #93) on checking the bolts came in handy. Mine looked good with no play at the timing gear and the bolt threads were all at a uniform depth looking at the back side of the cam shaft flanges.

2004 SMG @ 50300 Miles.

Much appreciated

icantthnkof1 · Fri, Jun-18-2010, 06:11:34 PM

Quote:

Originally Posted by Obioban

The exhaust bolts don't seem to be nearly the issue that the intake ones are, but they're cheap and super easy once you're already in there... So I'm going to do them.

Hey Obioban. Would you mind documenting the VANOS installation? I believe it's step 20 of OP's diy. It's the only part I'm unclear of.

Was thinking too. Since you live around the corner from me, would you be interested in doing this together? Looks like two sets of hands would make this a lot less aggrevating. I can supply the beer

**Obioban** · Fri, Jun-18-2010, 06:33:51 PM

Quote:

Originally Posted by icantthnkof1

Hey Obioban. Would you mind documenting the VANOS installation? I believe it's step 20 of OP's diy. It's the only part I'm unclear of.

Was thinking too. Since you live around the corner from me, would you be interested in doing this together? Looks like two sets of hands would make this a lot less aggrevating. I can supply the beer

Sure, though I'm still 2000 miles out.

I would rather do it alone, though... don't want to be distracted at all during this particular process...

Thu, Jun-17-2010, 11:53:44 PM	#111
king-rb dammmmmmmmit! Join Date: Apr 2005 Posts: 2,353 Reputation: 0 Location: San Diego	Top notch DIY, without a doubt! Quick question that I am not grasping at the moment. What is actually causing the bolts to be "cut" in the middle of the threads? I understand that when they are loose there is play, but what is actually cutting them?? __________________

Fri, Jun-18-2010, 01:13:08 AM	#113
m3e46freak M3 Freq Join Date: Jun 2007 Posts: 11,461 In the garage: '11 BMW M3 Reputation: 0 Location: 'Merica, but ask me where I wish I was...	Great write up ...but good lord that is a struggle. __________________ 04 Jet Black SMG - NAV Cinnamon Sonic Tuning Spacers 15mm Alcantara steering with and pillars and boots Valentine V1 Laser Interceptor BMC filter Full real carbon trim to include seat backs and paddles Scorza mufflers CSL bumper and trunk ST coil OEM Roof m3e46freak@yahoo.com for outside contacting

Fri, Jun-18-2010, 03:30:40 AM	#115
casper3t Registered User Join Date: Feb 2008 Posts: 1,716 In the garage: '02 BMW M3 Reputation: 0 Location: Anaheim	that it? you just take off the vanos and reinstall without recalibrating it? the bmw tech lied to me that it need to be recalibrated with air tools and they wanted to charge me 1500 to replace the vanos gasket. __________________ '02 Euro Tuned///M3 6spd Carbon Black cover with a layer of dust and Grey Int. Suspension: Koni Adj with Vogtland Springs, UUC FCAB, RE RTABS and GC Street Camber Plates

Fri, Jun-18-2010, 02:36:14 PM	#116
Highpower11 Registered User Join Date: Sep 2008 Posts: 605 Reputation: 0 Location: NH	After reviewing this thread and the OP's original thread shown here... http://www.m3forum.net/m3forum/showthread.php?t=319590 Just a thought... but if the bolts are determined to be secure and not loose per the above thread, is it possible to stake the rear of the cam bolts to their respective housing? We can get to the back of the bolts fairly easily and thus could be done quite easily I assume as a preventive measure, before they loosen, without having to disassemble the vanos unit. Perhaps a tech can chime in here or even a M.E. If this were possible and successful, it would surely make life a lot easier for those that have not yet had their bolts begin to back-out. __________________ ___________________ 06 /// M3 ZCP, 6MT, Interlagos Blau Metallic \ M-Alcantara\ Volk RE30\ VMR 701 (winter)\ CDV delete\ ESS ECU Tune\ RPI Scoops\ BMC Filter\ Turner aluminum Race Pedals\ Rogue FR 10mm spacers\ Rogue RSM\ Vogtland Springs\ \ V1 Hardwire\ DICE/iPhone\ Smoked corners\ painted reflectors\ ZHP illuminated Alcantara shift knob\ HID fog's\ LightWerkz TFX\ Nav, Power seats & Sunroof delete\ Coming Soon: Euro Headers & Cats

Fri, Jun-18-2010, 04:05:46 PM	#118
jetmech Registered User Join Date: Mar 2010 Posts: 200 Reputation: 0 Location: McHenry	Thanks to the OP for this writeup. I just had my valve cover off to do the valve clearance check so the "Mini DIY" (see post #93) on checking the bolts came in handy. Mine looked good with no play at the timing gear and the bolt threads were all at a uniform depth looking at the back side of the cam shaft flanges. 2004 SMG @ 50300 Miles. Much appreciated __________________ Jetmech Saving pilots lives, one flight at a time 04 M3 SMG Oxford Green Previous BMW's: 97 M3/4 (M5) 98 328iC (Auto) 94 325i (M5)

Fri, Jun-18-2010, 03:14:51 AM	#114
JRM3 Registered User Join Date: Mar 2007 Posts: 1,038 Reputation: 0 Location: Austin	20. Take a break. You need a lot of patience to get the VANOS unit back on. Had your break? Good, proceed... With the vanos unit in one hand. and your two wrenches ( 7mm and 10mm) in the other, simultaneously align the Vanos unit and tighten up the two mating shafts on the intake and exhaust sides. I have no pictures of this, because I only have 2 hands. It will take a few tries to get this done. It spent probably an hour getting this part done. Make sure the markes you made previously line up. OH - and don't forget to replace the VANOS gasket that goes between the unit and the engine. It would have been really helpful to have a helper at this point. But I'm a lone warrior, and I got it done alone. In your statement above, can you expand on the line up you are speaking about. I'm not sure I understand....

Fri, Jun-18-2010, 03:50:12 PM	#117
tjpatte Registered User Join Date: Apr 2007 Posts: 482 Reputation: 0 Location: San Diego	Not too sure you would want to put a lateral shock load on the camshafts like that? Tom

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