Lead from top end?

[SaltyNC]

Do you think there is anything on the top end of our S54 engines that could cause lead to increase in the oil? I have a very strange vanos knock. It's not a rattle. I dropped it off, today, and it goes under the ratchet on Monday. It's probably bearings causing the lead increase, but I was wondering if there is anything related to the vanos that could possibly cause elevated lead levels. Wishful thinking? ;-)


At any rate, really looking forward to finding out what is causing this weird vanos knock, and getting back to driving my Z4MR.

Salty

[wdb]

Subbed

[SaltyNC]

Quick update -- vanos is off and while the lead question is still unanswered, and probably is my bearings, the vanos knock has been determined. The bolts holding my exhaust side were OK, but the bolts holding the intake side sprocket were about to fail. All of the bolts were very loose and about to shear off. The thought is that the knock was actually the sprocket slop. All of my engine internals on the top end looked great, like a brand new engine, so woot!

Salty

[StickMon]

Glad you found it!
Mine was intake, as well. 3 heads off.
It's always intake. It must get more action than the exhaust.

[SaltyNC]

Thanks, Stickmon!

We used Loctite on the new bolts. They won't be working loose, and shouldn't fail like the old ones. Amazing that the engine mount bolts and vanos bolts were both too weak. Dang bean counters, probably.

After the bearings, if I can get 165K like you, I'll be a happy man.

Salty

[Finnegan]

Originally Posted by SaltyNC

Thanks, Stickmon!

We used Loctite on the new bolts. They won't be working loose, and shouldn't fail like the old ones. Amazing that the engine mount bolts and vanos bolts were both too weak. Dang bean counters, probably.

After the bearings, if I can get 165K like you, I'll be a happy man.

Salty

Nice save!

Lead is going to be bearings. Git'er done! Way cheaper than the alternatives.

[SaltyNC]

Originally Posted by Finnegan

Nice save!

Lead is going to be bearings. Git'er done! Way cheaper than the alternatives.

I hear ya, and know you're right. I'm going to get it done very soon after I get my car back from the vanos work. I'm still deciding whether to go with WPC bearings or BE bearings with the greater clearance and special BE-ARP bolts (not the same as regular ARP bolts).

Salty

[Finnegan]

Originally Posted by SaltyNC

I hear ya, and know you're right. I'm going to get it done very soon after I get my car back from the vanos work. I'm still deciding whether to go with WPC bearings or BE bearings with the greater clearance and special BE-ARP bolts (not the same as regular ARP bolts).

Salty

I've asked a few folks and the consensus is WPC and OEM bolts. That's the M3Forum consensus as well FWIW.

[SaltyNC]

Originally Posted by Finnegan

I've asked a few folks and the consensus is WPC and OEM bolts. That's the M3Forum consensus as well FWIW.

I've found that, as well, but I do wonder if the reason more S54 owners aren't going with the BE bearings with the greater clearance is because more people haven't tried them, yet. The S65 and S85 guys are moving to BE bearings, and so far, so good, but there are questions remaining in my mind. I think increasing the clearance with the 10W60 probably solves the bearing wear issue, but what other effects does it have on the system as a whole. I'm not tracking my car or even driving it very hard in day to day use, so losing a small amount of power isn't a concern for me, if it addresses the bearing wear issue.

The guy doing my vanos work said my top end looked like a brand new engine, the previous owner never tracked it, he was an older guy (in fact, he's dead now), and so I just don't think my engine was stressed for the first 30K of its life. I certainly didn't stress it. I always warmed up properly, waiting for the oil to completely warm up before doing any spirited driving, and even then, it was mild spirited driving, never stomping full throttle, never hard launches, etc. What little I do, it tends to be on curvy mountain roads. Like Stickmon, my clutches tend to last more than 160K miles. I'm easy like Sunday morning. Heck, my license plate even says SLOW. ;-) So, with all that said, just past 40K miles, my lead went off the charts to the 40's. It's a real mystery to me.

There are two things I've considered. Did the previous owner lug the engine frequently, because he wasn't skilled with driving a manual? That is an unknown and might explain the bearing wear. The other is that due to the design of the S54, we have dry starts. But the dry start doesn't explain why some S54s don't show much bearing wear at 80K while others are down to the copper and look like they are on the verge of spinning at 30K.

I know this subject has been beaten to death. I'm aware of the expensive fixes, but I wonder if simply reducing the bearing clearance might be an inexpensive fix for the S54 crowd like it so far seems to be for the S65 and S85 crowd.

I guess the only comfort we can take away is that compared to the S65, our bearing wear seems to be mild. ;-)

Salty

[Finnegan]

Those are all great questions. And lugging the engine might be the other side of the high-rev wear coin. We just never know

The BE bearing arguments are good ones. I don't know, getting the work done is the important thing and BE might provide 10s or 50s k of miles. Maybe give it a shot?

[SaltyNC]

Providing some additional info on the BE bearings for the S54. They are actually made by the same company that makes the OEM.

"This bearing is targeting buys who are doing rebuilds and want something better than stock. You do get a very small increase in clearance at the same time."

So, they basically made the S54 bearings slightly thinner, but then add the anti-friction layer, and overall thickness is very, very close to the OEM.

I'm going to go this route, and the BE-ARP bolts sound great. Simple torque procedure and they don't distort like the ARP bolts do.

Salty

[Finnegan]

Originally Posted by SaltyNC

Providing some additional info on the BE bearings for the S54. They are actually made by the same company that makes the OEM.

"This bearing is targeting buys who are doing rebuilds and want something better than stock. You do get a very small increase in clearance at the same time."

So, they basically made the S54 bearings slightly thinner, but then add the anti-friction layer, and overall thickness is very, very close to the OEM.

I'm going to go this route, and the BE-ARP bolts sound great. Simple torque procedure and they don't distort like the ARP bolts do.

Salty

Great! Makes good sense, I like the idea of another solution. Keep us posted!