Originally Posted By: 09_GXP
Originally Posted By: dustyroads
Over in the diesel uoa forum, I've been talking about learning of aluminum and potassium leaching from the intercooler's brazing flux. I'm wondering if that's what you are looking at here. Maybe there's a little bit of lead in the brazing flux, too?
Detroit Diesel says that the first three oci's can show as much as 150ppm aluminum and 300 ppm of potassium. My second oci showed an increase in lead as well. Sorry to bring up a big diesel here but the info is fresh in my mind and thought I'd throw it out there.
Hmmm... definitely something to mention and look at as a possible source. I know the flux leaching is very supplied dependent and we have t seen other 2.7L UOAs with the same results. But with a new engine it is possible some parts were dual sourced to ramp up production.
I actually spent some time in a past job working through engine issues that were caused by a certain type of flux being used. I'll have to pull up my old notes and see if anything is relevant. For reference the UOAs here were for the 3rd and 4th OCIs.
Well, you're way ahead of me then. I only learned of leaching of the flux this past july when I did my first test of a factory fill. Would be neat to see what you find out (if you have any luck in your investigation).
Have you ever heard of lead in the brazing flux? I just wondered if that was even possible, I'm unaware of the potential for that. With my Detroit, my factory fill went about 30k miles and showed a considerable amount of aluminum and potassium but no lead. My second oci was 37k miles with a lot more aluminum, potassium and a good bit (12ppm) of lead. I do have bearings with lead in them as a potential source, though.