2007 Z4 M coupe, new buyer questions. *UPDATED* Bought one.

[JustinHEMI]

Greetings all!

Hopping over here from the M2 forums.

I am considering buying a 2007 Z4 M coupe with about 125K miles on it. I am in conversation with the seller, and I was able to get the VIN and pull a car fax. It shows 3 owners and a good maintenance history with a reputable shop in the seller's location (going back to 2014 with him).

The rod bearings and vanos have not been done.

What I'm reading is that these should be done preventatively on the S54 and I'm wondering if it's something that I should consider immediately if I decide to buy this car? Should it be factored into the deal?

For the price he's asking, I've seen other cars with these items done.

The car is otherwise beautiful and well maintained per the carfax.

Thanks!

[GuidoK]

at 125k miles always do the rodbearings at once. (not that you have to trailer the car home...but don't wait with it)
Target interval for rodbearings is 50k miles.
With changing the rodbearings also fit a new oil pump control piston (part not available at dealers, but certain tuners sell these)
Vanos should also be inspected pretty much immediately (check both the little vanos bolts inside that hold the sprocket (they can shear off), and the vanos hub inside (broken tabs)), and with 125k miles, also the wear on camshafts/cam followers should be inspected (if there's wear, that's a costly one..).
Also check on broken chain guide rails.

The whole "maintenance with a reputable shop" is imho not worh much when at 125k the rodbearings have never been changed in this engine.
Rodbearings on an s54/s65/s85 is like the IMS bearing on porsche. Every shop should know about this and these issues go back a long time. Pretty much to the euro s50 days, so at least 25 years it's a known problem.

In germany there are shops who fit new rodbearings and the oil pump pressure piston for €1000-€1200 (that's including the parts), so that's imho very reasonable for a 50k miles recurring maintenance interval, considering it's a high rev race derived engine. (the cost would tranlate to 2,7ct US per mile). Don't know the going rate at US shops.

For the rest check (or rather replace) the bolts from the driverside engine mount (the bolts that go in the block), check the input oil seal on the diff (so where the propshaft goes into the diff), and check the front control arm rear bushings.

[XMetal]

^^Agreed with GuidoK.

If you haven't already done so, take a look at my thread linked below and you'll see plenty of pictures of bearing wears at about 60k miles.

https://www.zpost.com/forums/showthr...y+oil+analysis

[JustinHEMI]

Originally Posted by GuidoK

at 125k miles always do this at once.
Target interval for rodbearings is 50k miles.
With changing the rodbearings also fit a new oil pump control piston (part not available at dealers, but certain tuners sell these)
Vanos should also be inspected pretty much immediately, and with 125k miles, also the wear on camshafts/cam followers should be inspected.

The whole "maintenance with a reputable shop" is imho not worh much when at 125k the rodbearings have never been changed in this engine.
Rodbearings on an s54/s65/s85 is like the IMS bearing on porsche. Every shop should know about this and these issues go back a long time. Pretty much to the euro s50 days, so at least 25 years it's a known problem.

In germany there are shops who fit rodbearings and the oil pump pressure piston for €1000-€1200 (that's including the parts), so that's imho very reasonable for a 50k miles recurring maintenance interval, considering it's a high rev race derived engine. (the cost would tranlate to 2,7ct US per mile)

Thank you for the insights. The shop in question quoted me 2500 for rod bearings and 2500 for vanos. (USD)

I have a request for a quote at a shop local to me.

[JustinHEMI]

Originally Posted by XMetal

^^Agreed with GuidoK.

If you haven't already done so, take a look at my thread linked below and you'll see plenty of pictures of bearing wears at about 60k miles.

https://www.zpost.com/forums/showthr...y+oil+analysis

Thank you!

[GuidoK]

Originally Posted by JustinHEMI

Thank you for the insights. The shop in question quoted me 2500 for rod bearings and 2500 for vanos. (USD)

I have a request for a quote at a shop local to me.

I don't know for sure but vanos rebuild seems a bit steep. Do you know exactly what you get for that €2500?
IF they fit the VAC vanos hub with improved (stronger) tabs it's maybe ok ($500 part). Beisan has a similar part ($400) and they also have an adapted oil pump disc, although I don't know if you need one if you fit the improved hub as they tackle the same problem, just in a different way.
But for that money they can just as easily fit on a new vanos front and completely forget the degrading vanos bolts or broken vanos exhaust hub.
Not tackeling these issues can result in the worst case in an engine writeoff.
It's not the price of the vanos fix that's important, but knowing exactly what they do for that money is.

Remember that if a shop does the rodbearings, they almost certainly wont fix/inspect the oil pump regulator piston problem as they won't be aware of it and the replacement piston is afaik not even for sale in the US.
This problem and fix was discovered and solved in Germany.
You can get it in Germany from burkhart engineering:
https://burkhart-engineering.com/en/...-incl-csl-bmw/
needed O-ring:
https://burkhart-engineering.com/en/...-the-oil-pump/

[JustinHEMI]

Originally Posted by GuidoK

I don't know for sure but vanos rebuild seems a bit steep. Do you know exactly what you get for that €2500?
IF they fit the VAC vanos hub with improved (stronger) tabs it's maybe ok ($500 part). Beisan has a similar part ($400) and they also have an adapted oil pump disc, although I don't know if you need one if you fit the improved hub as they tackle the same problem, just in a different way.
But for that money they can just as easily fit on a new vanos front and completely forget the degrading vanos bolts or broken vanos exhaust hub.
Not tackeling these issues can result in the worst case in an engine writeoff.
It's not the price of the vanos fix that's important, but knowing exactly what they do for that money is.

Remember that if a shop does the rodbearings, they almost certainly wont fix/inspect the oil pump regulator piston problem as they won't be aware of it and the replacement piston is afaik not even for sale in the US.
This problem and fix was discovered and solved in Germany.
You can get it in Germany from burkhart engineering:
https://burkhart-engineering.com/en/...-incl-csl-bmw/
needed O-ring:
https://burkhart-engineering.com/en/...-the-oil-pump/

I didn't get great detail from the rough estimate, but here's what they said,




"With mileage and age it is definitely not a bad idea to have the rod bearings completed and at a minimum the exhaust hub on the Vanos system. Cryo treated exhaust hub with valve adjustment runs about $2500 w/tax. Rod bearings with new motor mounts is about the same $2500 w/tax."

[GuidoK]

Ok, that's a bit cryptic for the vanos, but just the exhaust hub and valve adjustment for $2500 sounds a bit steep.
That exhaust hub is a ~$500 part, valve adjustment is pretty easy (maybe $100 for valve shims), so $1900 for work? This can easily be done in 1 day, do they then charge $240 or so/hour?

For that price I'd expect to have all the o-rings/seals in the vanos unit replaced.
But I'm a guy that does everything himself to the most meticulate standards, so I'm very fast with my critique on others....

But to give you an idea: this is the standard offer from Redish motorsports in the UK (one of the highest regarded shops in all of Europe when it comes to BMW related problems):
https://www.redish-motorsport.com/E4...ulRepairs.html

See what they all do for the £995 ($1300) vanos overhaul? (ok, some things are obvious, like a new vanos gasket, but still)
See the optional extra's?
And how cheap they are?

Either they specify the work way better, or you get more work/service for the money.
Everything you see there, so the complete internal vanos overhaul with all the orings etc (except the new coil pack), the improved exhaust hub, improved chain guide, valve clearance adjusted, would come to a total of £1639 ($2150)

And this is what they charge for rodbearings:
https://www.redish-motorsport.com/E4...ingShells.html

So all I can say is that your shop aint cheap.

MAybe you can negotiate a better price with more specific listing from what you exactly get for that price?

[JustinHEMI]

The seller said this shop was expensive and may be able to get it discounted, but it is the first shop I checked. I have requests for quotes out to other shops local to me.

At 125k, though, without these things done, for the money he's asking, I can do better, so I'm certainly going to see if he's willing to dicker based on these items not being done.

[GuidoK]

Ok, but keep in mind with every z4m you buy that has more than 50k on the clock, the rodbearings have to be replaces in an ideal situation.

The vanos exhaust hub: whether or not that's going to break is not a certain issue.
I know guys that have pampered their z4m and are one of the slowest drivers on the planet that had their tabs break on the exhaust hub, and I know people that have driven their car like they stole it and had no issues.
So if that warrants an upgrade if the tabs aren;t broken.. I'm not so sure.
But when doing the valve clearances, it never hurts to check.

I think the issue of broken vanos bolts (they wear because of looseing and the hub starts chattering until the bolts break), is a more important check to do.
I think those bolts breaking can also inflict more damage than the broken exhaust hub.
This is what that wear on the little bolts looks like:


But both the inspection of those bolts as inspection of that vanos exhaust hub requires the removal of the vanos, so you do one, you do the other.

This is what broken tabs on the vanos exhaust hub look like:


So to get to those little bolts to inspect, you remove the exhaust and intake hubs. So by inspecting the vanos bolts, you can't miss the exhaust hub. But vice versa you can (inspecting the exhaust hub doesn't automatically mean inspecting the bolts)

[JustinHEMI]

Originally Posted by GuidoK

Ok, but keep in mind with every z4m you buy that has more than 50k on the clock, the rodbearings have to be replaces in an ideal situation.

The vanos exhaust hub: whether or not that's going to break is not a certain issue.
I know guys that have pampered their z4m and are one of the slowest drivers on the planet that had their tabs break on the exhaust hub, and I know people that have driven their car like they stole it and had no issues.
So if that warrants an upgrade if the tabs aren;t broken.. I'm not so sure.
But when doing the valve clearances, it never hurts to check.

I think the issue of broken vanos bolts (they wear because of looseing and the hub starts chattering until the bolts break), is a more important check to do.
I think those bolts breaking can also inflict more damage than the broken exhaust hub.
This is what that wear on the little bolts looks like:


But both the inspection of those bolts as inspection of that vanos exhaust hub requires the removal of the vanos, so you do one, you do the other.

This is what broken tabs on the vanos exhaust hub look like:


So to get to those little bolts to inspect, you remove the exhaust and intake hubs. So by inspecting the vanos bolts, you can't miss the exhaust hub. But vice versa you can (inspecting the exhaust hub doesn't automatically mean inspecting the bolts)

Thank you for all the information and the insights!

[JustinHEMI]

I was able to work a deal with the seller that was amicable for both of us considering these items that need to be completed!

Here's my new baby!

[Piper1]

Gorgeous! Congrats

[wdb]

Congratulations from another eastern PA Interlagos coupe owner!

[3798j]

Nice!

[Colemme]

The car is stunning, congratulations!

[JustinHEMI]

Thanks all!

[grannyknot]

That's the colour I would have chosen if I had had the chance.

[jwolf]

I think by the time your factor in the high mileage needs, a lower miles car could be a bargain. I would not want to gamble on the crank journals with those miles. It would have to be a really good deal to offset things.

[pungo]

Congrats on the new ride, looks awesome

I found a extremely low mileage Interlagos Blue one in eastern PA, must have been popular there.

[Angelito]

Very nice, congratulations. To add an additional recommendation to GuidoK's post, you can also check out DrVanos at https://drvanos.com/collections/s54-...ucts/s54-vanos

He's located in Texas; reasonable price once you return your core. Enjoy your new acquisition, cheers!

[JustinHEMI]

All I can say is WOW. Picked it up in the Knoxville area and began the drive home, taking the blue ridge parkway part of the way. For a car of her vintage and miles, she has exceeded my expectations in handling and tightness. The only way I could tell she's 15 years old was cosmetically.

I did have a scare on the way home, and picked up a slight dent.

I was in left lane with a tractor trailer in the right. He started moving over, must not have seen me, and began driving me off the road. I am lucky I didn't smash into the guard rail but I did get in the dirt and the tail got sideways.

She (and I) handled it with aplomb, and the very back of the rig touched the front right fender just a smidge. I think I can probably just pop it back out with my fingers.

Not the way I wanted to see how she handled, but after the moment of terror, I was so happy with how controllable she is even when the tail is loose.

The pedals are also perfectly positioned for heel/toe. I wonder why BMW effed that up in my M2C? Probably to convince us to use auto rev match. Anyway, I digress.

The cops came and took a report, by the way.

I'm trying to decide if I'm going to renew any of her 15 year old petina. I kind of like the character that it gives her as a driver's car. Of course I'll keep mechanicals refreshed. Oh and the headlights are yellow so I'll restore those.

The first owner was a California older lady that babied it but kept it parked in the sun so there's some sun bleaching on logos and such too.

All in all, very happy.