Timing Chain Guides and VANOS - A Couple of Questions....

[dannyzabolotny]

I'm replacing guides, OSV, chains, tensioners, everything. How involved is it to rebuild the VANOS?
Anyone have any experience with this?

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How difficult was the VANOS. It looks like I need special tools.

I've rebuilt three sets of Vanos units. Replacing the seals isn't hard, it just requires some patience and the ability to follow directions.

Pressing the Vanos units is the hard part, because you need a massive amount of force. A solid breaker bar and a sturdy vice is what you'll need to press the Vanos. You'll need the Vanos press tools, but a lot of M62tu timing kits come with the Vanos press tools. Make sure that the kit you rent/buy has those included.

[clarkitect]

Yeah you can do that too. I have never adjusted mine, so I just removed the nut on the pump sprocket, slipped the old chain off, and put the new in there. Right within tolerance.

I started the car today for the first time. I was so nervous lol. It fired right up. Not a single rattle or noise either, but I wouldn't expect that with how tight all the new chains were with the new guides. It was so tight the cover itself was tensioning the chain on the passenger side. So far so good.

Well done man! Yeah it takes several minutes of staring at the engine in contemplation to work up the courage to turn that key for the first time. It's a great sense of accomplishment when done.

I'm replacing guides, OSV, chains, tensioners, everything. How involved is it to rebuild the VANOS?
Anyone have any experience with this?

- - - Updated - - -

How difficult was the VANOS. It looks like I need special tools.

Like Danny said above- not that difficult. If you're doing all that work don't skip out on rebuilding the vanos. I almost did but am so glad I decided to bite the bullet and do the rebuild. No sense skipping it when you're already all the way in there.

[ebida3]

You guys are an inspiration for me. The VANOS rebuild procedure seems a little convoluted. Example, the teflon seal gets wavy then you have to smoothen it out while making sure it sits right.
I guess trying to process it in my mind without it in front of me it throwing me off.
And I understand that you basically mark the asproket and unit then turn down the press one complete turn. Then making sure there is no gap what so ever between the lip and the gasket.
Any surprises other than the force needed to press it?
Thanx in advance. Once again you guys are my heros, at peas for the moment, lol!
Marc

[dannyzabolotny]

No real surprises, just follow the instructions and be patient. The Teflon o-ring is a bit of a pain in the ass, but if you take your time with it you'll be fine. The important thing is to not rip it by shoving it in too hard. Before you put the new Teflon rings in, put them in a cup of hot water for a few minutes. That'll soften them up and make them pliable and easier to work with.

I'm happy to help with this stuff, because it's just giving back to the wonderful community here. I learned so much from these forums when I was starting out.

[purplecty]

Maybe a good idea to get the recommended extra ring that is fully refundable as well just in case...

[wagzilla]

Hello guys I have a 2000 740i and I think its time to do my Vanos also! sounds like a good time, I started looking for a tool not sure witch one to get?? any idea's

thanks James

[Steve Sposato]

You guys are an inspiration for me. The VANOS rebuild procedure seems a little convoluted. Example, the teflon seal gets wavy then you have to smoothen it out while making sure it sits right. I guess trying to process it in my mind without it in front of me it throwing me off. And I understand that you basically mark the asproket and unit then turn down the press one complete turn. Then making sure there is no gap what so ever between the lip and the gasket. Any surprises other than the force needed to press it? Thanx in advance. Once again you guys are my heros, at peas for the moment, lol! Marc

I did mine and the only other thing I would say is to make sure you grease the screw on the press you use the grease makes it so much easier to screw it down.

[Steve Sposato]

Hello guys I have a 2000 740i and I think its time to do my Vanos also! sounds like a good time, I started looking for a tool not sure witch one to get?? any idea's thanks James

Get the ones from Beisan I did and they worked great with using his seals

[Antipodean]

Completed the strip-down this weekend:



It all went fine although a couple of comments. The "Jesus Bolt" gave in pretty easily - I used the "Pelican" crank holder and a 30" 3/4" breaker bar (no pipe extension) and it yielded without much of a fight. What did surprise me were the cam sprocket bolts. I really had to haul on these - made me doubt they were left-hand thread (checked the Besian instructions and TIS twice to make sure). A lot more torque than I would have thought.

I will send the VANOS units out for a rebuild I think - any recommendations?

Then cleaning it all up and the rebuild starts (the fun part).

Rob.

[clarkitect]

You'd save a ton of money just rebuilding the Vanos on your own. It's so easy that once you've done it you'll wonder why you would consider spending all that money for Dr. Vanos or one of those guys to do rebuild them.

Nice work BTW.

[Antipodean]

More progress. I sent the VANOS units off to Vanosman (George) who rebuilt them with the Besian seals. George has been very helpful and turned them around very quickly for a very reasonable price. Anyway its all cleaned up and reinstalled with new guides, chains, valves and seals. Just have to do the timing and torque the cams. I pulled the intake as I noticed the retaining fiber washer on some of the injector seals had shattered so need to replace those. Oh well. I did the valley pan last year so checked it was all still good and will check the torque on the bolts in any case.

[NordmanMg]

Don't forget to spin Vanos sprocket centers all the way back, counter clockwise before tightening
and don't forget to tighten stud on the U-rail to hold CCV neck in place

[cazal740i]

Torque the Exhaust sprockets to 92ft lbs and both intakes at 81ft lbs
Sure helps to have a buddy counter hold the Cam's from turning and the blocks from lifting. U can be off timing if the blocks lift 1mm off.

[racer2086]

I don't know about the facelift cars, but the TIS stated 15Nm for the cam and exhaust sprockets on my prefacelift. They were very easy to loosen also. Don't know where 92 and 81 is coming from unless the Vanos cars are cranked on there.

[cazal740i]

I don't know about the facelift cars, but the TIS stated 15Nm for the cam and exhaust sprockets on my prefacelift. They were very easy to loosen also. Don't know where 92 and 81 is coming from unless the Vanos cars are cranked on there.

Per Bentley e38 99-01

[dannyzabolotny]

92 and 81 are correct for the camshaft sprocket bolts, I did timing chain guides on three M62tu's last year. You definitely want to have somebody counter hold the camshafts so they stay in place while torquing the camshaft sprocket bolts, otherwise you might get a timing over-advanced error when you run the engine.

[Antipodean]

Don't forget to spin Vanos sprocket centers all the way back, counter clockwise before tightening
and don't forget to tighten stud on the U-rail to hold CCV neck in place

Yep - I would have missed the hex stud in the U-rail for the CCV. That one is not obvious, but is documented in the DIY so did catch it. 91/82ft lb is the correct torque - I really had to haul on the LH thread cam bolts to release them and there is no locating key, the sprockets are held in place by the torque.

[NordmanMg]

I don't know about the facelift cars, but the TIS stated 15Nm for the cam and exhaust sprockets on my prefacelift. They were very easy to loosen also. Don't know where 92 and 81 is coming from unless the Vanos cars are cranked on there.

on non vanos engine cam sprockets held with 6 tiny bolts (15n/m each) , on newer engines there is only one in a middle (92 & 81n/m)

[racer2086]

on non vanos engine cam sprockets held with 6 tiny bolts (15n/m each) , on newer engines there is only one in a middle (92 & 81n/m)

Ohhhhh...that makes sense. I was going to ask why the difference. I didn't realize it was just one big bolt for the TU engines, I haven't had a TU apart for guides. My prefacelift is just like you say...6 E-torx bolts on each sprocket. 15nM. I was wondering why everyone was talking about counter holding the cams, since it was so easy to get mine on and off. OP good job! You're moving along!

[Antipodean]

More progress this weekend. Got the cams timed - double checked and adjusted after two rotations of the crank so as to be sure. Front covers on, and new crank bolt installed and torqued. Next weekend can start on bolting back up all the external bits, add fluids and will be ready to give it a start. Fingers crossed!

[clarkitect]

Looking good.

[garycw]

Looks good and a good bit of work. My question are ALL these e38's going to have timing chain issue or does it just seem that way from all the threads on it ??

[dannyzabolotny]

Looks good and a good bit of work. My question are ALL these e38's going to have timing chain issue or does it just seem that way from all the threads on it ??

Most E38's will eventually have this issue, since the guide plastic inevitably wears out and breaks apart. However, the older pre-Vanos E38's usually go for longer before the guides fail, and there are a few E38's that will likely never have the issue: the 1995 740il, because it uses an M60 engine with a double timing chain, and the 1995-2001 750il, because the M73 engine only has one timing chain that's not prone to guide failure. So if you never want guide failure, buy either a super old 740il, or any 750il.

[garycw]

Thanks, that's what I was afraid of sitting at 131k mi and now my daily driver. Just not sure how much more $ I can justifiably put in it. Purchased as occasional driver in '09 for $7k. Since have put around $4500 or more in it.

[NordmanMg]

Since 2009 you spent only 4500? You are lucky my friend