S54 (2002) M3 Analysis and High Silicon

[billdouglas30]

Hi All,

Looking for feedback on the attached report. Currently I have the new Shell 10W60 M Twin Turbo Power in the car. OAI does not seem to have a baseline for this oil so I actually think the viscosity, calcium, and possibly oxidation are fine.

Looking for feedback on the silicon though. I strongly feel this this is related to seeping from RTV I used on the valve cover gasket 2500 miles ago. After the analysis in May I changed the oil and also the air filter. I made sure everything was secure and checked for leaks. I don't have any idle / drivability issues or lean codes. Question is should I have any concern about an intake leak given this history? There does not appear to be any increasing wear (aside from the iron maybe being a bit high for the mileage on the oil).

Thoughts?

 

[billdouglas30]

Moving to correct section

 

[zeng]

Oil looks good and serviceable , despite viscosity shearing and fuel dilution.
There is no concern for air intake leaks as RTV may have contributed to high silicon readings.
Wear rates, oxidation and sulfation generally ok.

 

[deven]

They are all kinda high for only 1700 miles. Check all your hoses and reinstall the air filter just to make sure.

 

[UltrafanUK]

Originally Posted By: zeng
Oil looks good and serviceable , despite viscosity shearing and fuel dilution.
There is no concern for air intake leaks as RTV may have contributed to high silicon readings.
Wear rates, oxidation and sulfation generally ok.


I agree and some 10w60 oils are only just inside the 50 range and when combined with their use of a lot of viscosity improvers that make such oils more prone to high temp shearing, will often finish up in the 40 grade range.
The fuel contamination is not so good in the longer term, so try using a major brand fuel additive every oil change to see if it's just gummed up injectors and make sure you do at least 30 mins of driving before taking an oil sample.

 

[jayg]

Originally Posted By: UltrafanUK
Originally Posted By: zeng
Oil looks good and serviceable , despite viscosity shearing and fuel dilution.
There is no concern for air intake leaks as RTV may have contributed to high silicon readings.
Wear rates, oxidation and sulfation generally ok.


I agree and some 10w60 oils are only just inside the 50 range and when combined with their use of a lot of viscosity improvers that make such oils more prone to high temp shearing, will often finish up in the 40 grade range.
The fuel contamination is not so good in the longer term, so try using a major brand fuel additive every oil change to see if it's just gummed up injectors and make sure you do at least 30 mins of driving before taking an oil sample.


This doesn't sound like the cause of the dilution to me. If they are "gummed up" how are they supplying more fuel than they need?

Any extended idling or lots of short tips would seem more plausible to me.

 

[UltrafanUK]

If the injector tips or body gum up it results in a bad spray pattern which looks similar to blown or worn out injector tips. If you use top of the range fuel it should contain additives that prevent gum formation, but most folks don't do that as it's expensive, so occasional use of a good fuel additive or direct feed injection system cleaner can help a lot to make sure the injectors stay clean.

The ECU will supply more fuel to gummed up injectors in order to maintain the desired RPM than it would to clean injectors.

My TDI does a lot of short tripping in winter and did get a UOA based warning for a trace of fuel (Less than 0.5%), so I filled the fuel filter with LM Diesel Purge when the element was changed. The next few UOA results had a higher flashpoint and no warning for fuel contamination.
Gum formation is more of an issue when you use both low power and cheap diesel or petrol.

Obviously there is no way of knowing the cause of the fuel contamination until the OP tries an injection system cleaner.

 

[jayg]

Originally Posted By: UltrafanUK


Obviously there is no way of knowing the cause of the fuel contamination until the OP tries an injection system cleaner.


I would still say that would be inconclusive. Pulling the injectors and having them flow tested would be the only true way of knowing rather than speculating if a few bottles of Techron did anything.

 

[billdouglas30]

Hey guys - thanks for your thoughts. I live in the city of Chicago so I will have short trips no matter how much I try to limit it. I'd think if I had an injector issue I would have other symptoms, not sure. I can try a bottle of cleaner as I don't know the last time that would have been done.

I was avoiding Techron though, can't that skew the results of the UOA?

 

[billdouglas30]

Another thought - I used this for my transfer pump

https://www.amazon.com/gp/product/B00KB8...Q9N4VM36WM786EF

Do you think it could be causing contamination or is that generally not a concern?

 

[UltrafanUK]

I don't tend to suggest expensive tests like removing the injectors and getting the spray patterns or flow rates checked. That only needs doing if the fuel additive fails to see if the tips are blown out.
About half of all injectors sent to Bosch recon centers are perfectly OK after they have been cleaned, which could have been done without removing them. Around 40% have blown out tips caused by bad fuel filters and only a few are cracked or badly corroded and beyond rebuild limits.

 

[UltrafanUK]

I've used those types of small oil pumps to take a sample from various diesels and never seen it result in high Silicon readings etc.

New sealants can cause very high Si readings and if you are concerned the only way to tell the difference is to get a particle count UOA.

 

[jayg]

Originally Posted By: UltrafanUK
I don't tend to suggest expensive tests like removing the injectors and getting the spray patterns or flow rates checked. That only needs doing if the fuel additive fails to see if the tips are blown out.
About half of all injectors sent to Bosch recon centers are perfectly OK after they have been cleaned, which could have been done without removing them. Around 40% have blown out tips caused by bad fuel filters and only a few are cracked or badly corroded and beyond rebuild limits.


But how would you know if the additive cured your problem? I wouldn't count on doing UOA's multiple times to see if it shows up on that.

Maybe it's expensive to send the injectors to be flow tested and cleaned in the UK and certainly if Bosch did it, but there are several independent reputable places in the US that will do it for a very reasonable price.

 

[billdouglas30]

Late update on this but:

1) I found a bad CCV system O-ring at bottom of airbox. Replaced hose.
2) I ran techron when i took it out of storage for a tank and just changed the oil. Will report back at end of season with updated UOA.