Jump to content
SAU Community

Recommended Posts

So, I wish I'd done an oil analysis before changing my turbos because my analysis shows elevated (53 ppm) levels of lead.

I don't have an analysis before this, so there is no trend. I'll do another change and analysis in 5k to establish a trend but I'm curious about whether this is just a sign of a steady decline? I have no knocks and oil pressure seems ok.  Is this something my engine can recover from or is it on borrowed time?

My mechanic did add some additive for stem seals in the last oil change which would be in this analysis. I'm not sure if that would affect anything. 

Also, the oil in this analysis is the first oil change I did with the car so I have no idea how long it had been since the previous one. I was given a service history but I don't fully trust these.

I know we don't have heaps of info and I'm kinda freaking out a bit, maybe prematurely. 

26 minutes ago, PranK said:

My mechanic did add some additive for stem seals in the last oil change which would be in this analysis. I'm not sure if that would affect anything. 

Find out how much lead is in that additive. Lead is normally a no-no, but seeing as it is an "additive" they might be able to get away with relatively low levels in their product, that could then turn up at the ppm level in the bulk oil.

I forgot to mention also that he cut the filter open and saw no glitter at all in there. 

6 minutes ago, GTSBoy said:

Find out how much lead is in that additive. Lead is normally a no-no, but seeing as it is an "additive" they might be able to get away with relatively low levels in their product, that could then turn up at the ppm level in the bulk oil.

Yep, I'l give him a call shortly. Fingers crossed! 

5 minutes ago, PranK said:

I'm reading that lead is likely from bearings. Can these be caught before it's too late or is it doomed already? 

 

Well, yeah, there is a (very thin) layer of soft lead on the surface of bearing shells to provide that first "cushion" against physical contact. Just because it is wearing off doesn't actually mean that the engine is dying. Of course, it can mean that the engine is dying.

If the engine is making no noises and the oil pressure is (mostly, as in most of the time) fine, then it could just be suffering under particular conditions. That could be startup, or maybe at some point in the normal operation cycle - or maybe the Beemer engine suffers under long left hand bend (see, highway on ramp) and the pressure drops. You'd need to try to work out if any such thing is happening and then determine if you need a bigger oil pump, or an Accusump or something.

39 minutes ago, GTSBoy said:

Well, yeah, there is a (very thin) layer of soft lead on the surface of bearing shells to provide that first "cushion" against physical contact. Just because it is wearing off doesn't actually mean that the engine is dying. Of course, it can mean that the engine is dying.

If the engine is making no noises and the oil pressure is (mostly, as in most of the time) fine, then it could just be suffering under particular conditions. That could be startup, or maybe at some point in the normal operation cycle - or maybe the Beemer engine suffers under long left hand bend (see, highway on ramp) and the pressure drops. You'd need to try to work out if any such thing is happening and then determine if you need a bigger oil pump, or an Accusump or something.

My engine has only an oil pressure switch from factory and I've installed an after market sensor that will alert me to pressure loss (https://www.sau.com.au/forums/topic/484431-my-bmw-335i/page/3/) . These engines can definitely feel long left/right handers which is why I added this sensor.

There are no other symptoms at all. No strange noises (in fact after the turbos were replaced the mechanic made a note of how sweet the engine was running), no smoke, no glitter in the filter, nada. I'm just a stress head with car issues, I hate there being anything at all wrong with my cars, even if its basic. I just immediately get anxious and start thinking about catastrophic failure.

 

Did the oil analysis include the acceptable range for Lead?

Last one i has said 1ppm is the limit and the engine I was testing had 74, 80 and 33 (was the race car, tested from brand new run in engine). It may not help to tell you the engine didn't last long, but they never did back then :)

19 minutes ago, Duncan said:

Did the oil analysis include the acceptable range for Lead?

Last one i has said 1ppm is the limit and the engine I was testing had 74, 80 and 33 (was the race car, tested from brand new run in engine). It may not help to tell you the engine didn't last long, but they never did back then :)

They didn't. This is their comments;

Quote

 

Lead wear rate abnormal. All other wear levels appear satisfactory for first sample. Silicon level (dirt/sealant material) satisfactory. Water content acceptable. Fuel dilution satisfactory. Viscosity low for specified oil grade. Action: Please confirm oil grade used in this component. Check for lower than typical oil pressure. Check for excessive engine knock at stall speed. As oil and filter(s) already changed, resample at a reduced service interval to monitor and establish wear trend. Note: In the absence of OEM specifications, general severity limits have been applied

 

I'm not sure why they don't have the OEM specs. 

I had a thought. I still haven't confirmed what additive was used but, the oil from this analysis was only 5,000 k's old and I believe was Mobil 1. Given that the oil was good and fresh, would there still be wear in the engine?

What I'm trying to articulate is, I understand that internal wear will happen with incorrect viscosity or not changing oil enough (and maybe other reasons also). But would the wear continue to occur when the oil is changed? Surely it would stop wearing, ie the damage was done? If thats the case, could this suggest maybe that the lead count is not wear?

I dont know if that makes sense. It does in my head.

15 minutes ago, PranK said:

But would the wear continue to occur when the oil is changed? Surely it would stop wearing, ie the damage was done? If thats the case, could this suggest maybe that the lead count is not wear?

What has an oil change got to do with whether wear is occurring or not? Wear may be facilitated by oil having been left in too long and broken down - but it is far more likely to be a mechanical issue (ie, pressure).

The thing with the tested oil being only 5000kms old makes it perhaps equally likely to be lead from bearings or lead from the additive.

Ok that makes sense, I was circling around the idea that this kind of wear would only occur with too long intervals between oil changes but I see what you're saying about the cause being something else.

Ok, so I just had a chat with my mechanic. He said there is no real source of lead in the engine, the bearings and pistons are aluminium and the rings I think he said are steel. He doesn't recall what additive he used but that along with the thicker 20w50 he used could be a source of lead.

It's put me at ease a little bit and I guess I'll just have to wait 5000 k's to do another change and see if anything is different. 

I appreciate you guys chiming in. I have a habit of immediately thinking worst case with things like this.

On 07/05/2024 at 10:25 AM, PranK said:

 

It's put me at ease a little bit and I guess I'll just have to wait 5000 k's to do another change and see if anything is different. 

 

You could just drive it normally and change it earlier. Mine has never crossed 2000k's even :banana:

19 hours ago, Duncan said:

well, FWIW mechanic is surely not right about the bearings being aluminium, they would be softer; mostly tin, nickel, copper and lead on a steel shell.

Just after I started to feel better about it all. :( 

I'm trying to find more info about the composition of the bearings. 

I found these ones; "The Upper and Lower bearing shells are comprised of a lead-free, Silver-based tri-metal material designed for extreme load applications." https://www.turnermotorsport.com/p-3929159-king-n55n54-rod-bearing-set-size-050-oversized/

And ChatGPT said; "The overlay material is often a soft metal alloy such as aluminum or a lead-based material."

I'm just going to send myself mad. I'll just drain and analyse in a few thousand k's.

The good news is, the quote from my mechanic for N53 bearings was relatively low and he’s fortunately an ex-BMW tech. I also went down this path - engine had a low oil pressure error from a missing cage in the filter housing. I ended up watching a million hours of rebuild videos until my oil analysis came back okay other than a shit tonne of boron *iirc* which was consistent with a leaking oil filter housing gasket. I also recall BMW N series bearings having a different material composition to normal.

  • Like 1

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • See if you can thermal epoxy a heatsink or two onto it?
    • The other problem was one of those "oh shit we are going to die moments". Basically the high spec Q50s have a full electric steering rack, and the povo ones had a regular hydraulic rack with an electric pump.  So couple of laps into session 5 as I came into turn 2 (big run off now, happily), the dash turned into a christmas tree and the steering became super heavy and I went well off. I assumed it was a tyre failure so limped to the pits, but everything was OK. But....the master warning light was still on so I checked the DTCs and saw – C13E6 “Heat Protection”. Yes, that bloody steering rack computer sitting where the oil cooler should be has its own sensors and error logic, and decided I was using the steering wheel too much. I really appreciated the helpful information in the manual (my bold) POSSIBLE CAUSE • Continuing the overloading steering (Sports driving in the circuit etc,) “DATA MONITOR” >> “C/M TEMPERATURE”. The rise of steering force motor internal temperature caused the protection function to operate. This is not a system malfunction. INSPECTION END So, basically the electric motor in the steering rack got to 150c, and it decided to shut down without warning for my safety. Didn't feel safe. Short term I'll see if I can duct some air to that motor (the engine bay is sealed pretty tight). Long term, depending on how often this happens, I'll look into swapping the povo spec electric/hydraulic rack in. While the rack should be fine the power supply to the pump will be a pain and might be best to deal with it when I add a PDM.
    • And finally, 2 problems I really need to sort.  Firstly as Matt said the auto trans is not happy as it gets hot - I couldn't log the temps but the gauge showed 90o. On the first day I took it out back in Feb, because the coolant was getting hot I never got to any auto trans issues; but on this day by late session 3 and then really clearly in 4 and 5 as it got hotter it just would not shift up. You can hear the issue really clearly at 12:55 and 16:20 on the vid. So the good news is, literally this week Ecutek finally released tuning for the jatco 7 speed. I'll have a chat to Racebox and see what they can do electrically to keep it cooler and to get the gears, if anything. That will likely take some R&D and can only really happen on track as it never gets even warm with road use. I've also picked up some eye wateringly expensive Redline D6 ATF to try, it had the highest viscosity I could find at 100o so we will see if that helps (just waiting for some oil pan gaskets so I can change it properly). If neither of those work I need to remove the coolant/trans interwarmer and the radiator cooler and go to an external cooler....somewhere.....(goodbye washer reservoir?), and if that fails give up on this mad idea and wait for Nissan to release the manual 400R
    • So, what else.... Power. I don't know what it is making because I haven't done a post tune dyno run yet; I will when I get a chance. It was 240rwkw dead stock. Conclusion from the day....it does not need a single kw more until I sort some other stuff. It comes on so hard that I could hear the twin N1 turbos on the R32 crying, and I just can't use what it has around a tight track with the current setup. Brakes. They are perfect. Hit them hard all day and they never felt like having an issue; you can see in the video we were making ground on much lighter cars on better tyres under brakes. They are standard (red sport) calipers, standard size discs in DBA5000 2 piece, Winmax pads and Motul RBF600 fluid, all from Matty at Racebrakes Sydney. Keeping in mind the car is more powerful than my R32 and weighs 1780, he clearly knows his shit. Suspension. This is one of the first areas I need to change. It has electronically controlled dampers from factory, but everything is just way too soft for track work even on the hardest setting (it is nice when hustling on country roads though). In particular it rolls into oversteer mid corner and pitches too much under hard braking so it becomes unstable eg in the turn 1 kink I need to brake early, turn through the kink then brake again so I don't pirouette like an AE86. I need to get some decent shocks with matched springs and sway bars ASAP, even if it is just a v1 setup until I work out a proper race/rally setup later. Tyres. I am running Yoko A052 in 235/45/18 all round, because that was what I could get in approximately the right height on wheels I had in the shed (Rays/Nismo 18x8 off the old Leaf actually!). As track tyres they are pretty poor; I note GTSBoy recently posted a porker comparo video including them where they were about the same as AD09.....that is nothing like a top line track tyre. I'll start getting that sorted but realistically I should get proper sized wheels first (likely 9.5 +38 front and 11 +55 at the rear, so a custom order, and I can't rotate them like the R32), then work out what the best tyre option is. BTW on that, Targa Tas had gone to road tyres instead of semi slicks now so that is a whole other world of choices to sort. Diff. This is the other thing that urgently needs to be addressed. It left massive 1s out of the fish hook all day, even when I was trying not too (you can also hear it reving on the video, and see the RPM rising too fast compared to speed in the data). It has an open diff that Infiniti optimistically called a B-LSD for "Brake Limited Slip Diff". It does good straight line standing start 11s but it is woeful on the track. Nismo seem to make a 2 way for it.
    • Also, I logged some data from the ECU for each session (mostly oil pressures and various temps, but also speed, revs etc, can't believe I forgot accelerator position). The Ecutek data loads nicely to datazap, I got good data from sessions 2, 3 and 4: https://datazap.me/u/duncanhandleyhgeconsultingcomau/250813-wakefield-session-2?log=0&data=7 https://datazap.me/u/duncanhandleyhgeconsultingcomau/250813-wakefield-session-3?log=0&data=6 https://datazap.me/u/duncanhandleyhgeconsultingcomau/250813-wakefield-session-4?log=0&data=6 Each session is cut into 3 files but loaded together, you can change between them in the top left. As the test sessions are mostly about the car, not me, I basically start by checking the oil pressure (good, or at least consistent all day). These have an electrically controlled oil pump which targets 25psi(!) at low load and 50 at high. I'm running a much thicker oil than recommended by nissan (they said 0w20, I'm running 10w40) so its a little higher. The main thing is that it doesn't drop too far, eg in the long left hand fish hook, or under brakes so I know I'm not getting oil surge. Good start. Then Oil and Coolant temp, plus intercooler and intake temps, like this: Keeping in mind ambient was about 5o at session 2, I'd say the oil temp is good. The coolant temp as OK but a big worry for hot days (it was getting to 110 back in Feb when it was 35o) so I need to keep addressing that. The water to air intercooler is working totally backwards where we get 5o air in the intake, squish/warm it in the turbos (unknown temp) then run it through the intercoolers which are say 65o max in this case, then the result is 20o air into the engine......the day was too atypical to draw a conclusion on that I think, in the united states of freedom they do a lot of upsizing the intercooler and heat exchanger cores to get those temps down but they were OK this time. The other interesting (but not concerning) part for me was the turbo speed vs boost graph: I circled an example from the main straight. With the tune boost peaks at around 18psi but it deliberately drops to about 14psi at redline because the turbos are tiny - they choke at high revs and just create more heat than power if you run them hard all the way. But you can also see the turbo speed at the same time; it raises from about 180,000rpm to 210,000rpm which the boost falls....imagine the turbine speed if they held 18psi to redline. The wastegates are electrically controlled so there is a heap of logic about boost target, actual boost, delta etc etc but it all seems to work well
×
×
  • Create New...