Subject: If he had not already spent money on the new head, I would say go for it... Author: ejonesie22 : member since March, 2004 : 1105 posts Posted on: 2008-06-16 11:01:38

If the engine was all in the same state, with the same miles on all components or at least most of them, I would say give it a try. But he has already invested in what is basically the hard part of a full engine rebuild. BMW head work is not cheap. To risk that investment with what in the end is nothing more than a delaying tactic could be throwing away good money. I for one am no fan of paying for the same thing twice.

To answer your question, yes I have seen people use various methods of clearing sludge including using the Amsoil flush. It can work in an old engine, if that is the only issue, and probably does more often than not. It's the "not" times that are the problem. I have “fixed” a couple of old tractors like that and a few old clunkers as well. The biggest draw back most often is an increase in seal and gasket leaks due to the fact that often the sludge has become part of the sealing equation. I have also personally seen deposits break loose and clog a vital oil passage. Of course this knowledge came after the fact and an engine tear down. That is not worth risking on a half rebuilt motor.

BTW You will find we also definitely avoid this path with auto transmission on BMWs.

Best tactic is to finish the job and finish the engine.

I am familiar with Amsoil, have been for 20 years and have read much of their literature and while it is a good oil and I have used it myself, I have always taken some of what they say with a grain or two of salt, as I have with most oils and other such products. As for Amsoil, they seem to blur the line between advertising and engineering at times, and their multilevel marketing approach does little to dissuade me from thinking that way.

For example their 25K to 35K change interval is a bit much, even if their oil can adsorb the acids and moisture to some extent. Engine oil may still be “good’, but the other reason we change oil is to remove the containments that build up as a by product of combustion. In all my years of study and reading on engines, in all the times I have worked with professional builders, in all the tech talk in Roundel I have read, as well as other periodicals, and the forums I have been on, I have never seen anyone in the field recommend going past 5000 miles before a change no matter the oil or if the manufacturer has a longer interval. Even Mobile One backed off the 25K bit some time ago. With full synths I do know some who recommend 10K changes in a passenger car, and if I had a motor with under 75k or so, I could see that for a while.

Unless the car is a turbo then it is 3-5K oil changes no matter if the oil came from the good Lord himself…



Evan Jones
1984 733i(s) Polaris Metallic 224,000 Miles
1986 745i Bronzit 166,000 Miles
1984 745i Delphin Gray 148,000 Miles (in progress)
1979 733i back to life supporting the others

oh and a '73 Alfa Spider, just because...

• burning oil...options? - ericbruckbauer 2008-06-13 16:36:15 (133 views)
  • Re: burning oil...options? (nt) - stritarja 2008-10-11 21:14:43 (17 views)
  • Re: burning oil...options? - donstevens 2008-09-06 16:37:25 (31 views)
  • Re: burning oil...options? - brkngmd 2008-06-15 20:11:04 (101 views)
    • If he had not already spent money on the new head, I would say go for it... - ejonesie22 2008-06-16 11:01:38 (101 views)
      • Re: If he had not already spent money on the new head, I would say go for it... - brkngmd 2008-06-17 06:50:07 (83 views)
        • Re: If he had not already spent money on the new head, I would say go for it... - ejonesie22 2008-06-17 11:23:25 (80 views)
          • Re: If he had not already spent money on the new head, I would say go for it... - brkngmd 2008-06-18 04:43:33 (65 views)
  • The only true option, finish the rebuild... - ejonesie22 2008-06-15 18:00:48 (85 views)
  • Re: burning oil...options? - brkngmd 2008-06-14 21:59:00 (88 views)
  • Re: burning oil...options? - brkngmd 2008-06-14 17:32:43 (81 views)
    • Re: burning oil...options? - ericbruckbauer 2008-06-14 19:57:22 (71 views)
  • Re: burning oil...options? - strobachyzoo 2008-06-14 09:27:17 (84 views)
  • One good option: Amsoil - brkngmd 2008-06-13 21:30:27 (99 views)
  • Blow by, bypassing the rings as you stated is indicated - kff 2008-06-13 16:44:25 (104 views)
    • It is def. Smoke off throttle. - ericbruckbauer 2008-06-17 09:19:24 (73 views)
      • Could also be through PCV : basic questions - brkngmd 2008-06-18 18:06:57 (85 views)
        • Re: Could also be through PCV : basic questions - ericbruckbauer 2008-06-21 18:57:58 (70 views)
          • I am betting money they used the wrong valve guides for the job or intalled them - Draleu 2008-06-23 01:02:29 (64 views)
          • Re: Could also be through PCV : basic questions - brkngmd 2008-06-21 23:19:52 (77 views)
            • Re: Could also be through PCV : basic questions - ericbruckbauer 2008-07-24 23:13:11 (44 views)