Prince George Vintage Motorcycle Club

Technical Section => Engine => Topic started by: Dennis on November 07, 2010, 11:17:52 PM

Title: How much metal in your oil would freak you out?
Post by: Dennis on November 07, 2010, 11:17:52 PM

For those who attended my last garage night, you are all witnesses that the Stray Cat 350 (a.k.a. a Honda CB350 twin) started, ran, and did not appear to be burning or leaking any oil.  It looked and ran good enough for me to want to swap it into the Ebay Bobber.

I pulled the engine and drained the oil.   The oil sat in the drain pan for about a week before I poured it into my waste oil bucket.  The last bit of oil (which had settled to the bottom) looked like metallic paint.  The oil was infused with small metal particles.  I was a bit alarmed, but put it down to "well the bike looked abused, so the last owner probably did not change the oil often." 

However, I then pulled the oil filter, which on a CB350 twin is a mechanical (centrifugal action), non disposable device which doesn't actually "filter" the oil, but spins it like the spin cycle on your washing machine, so the crud sticks to the inside of the cylinder walls where you can later wipe it clean.   The filter was full of metal flakes.  I scraped out at least a teaspoon of metal (probably more). 

I have not yet determined whether the metal is ferrous (steel) or nonferrous (aluminum), but the goo is in a magnetic tray for further analysis.   In any event, it is way more metal than I have ever found oozing around in all the important bits.

I don't want to tear this motor down more than I have to.  I am hoping that the metal I find is simply evidence that the previous owner never changed his oil or cleaned his filter, and the filter has successfully done exactly what it was supposed to have done. 

Any words of wisdom?  Similar experiences? 

At present my plan is to pull the clutch basket and get as close to the bottom end as I can without splitting the cases, and then use a spay bottle of diesel and try to rinse out as much residual oil (and further bits of metal) as possible.

Any thoughts and comments from my learned friends would be greatly appreciated.

Title: Re: How much metal in your oil would freak you out?
Post by: Hans on November 08, 2010, 09:21:57 PM

It's a honda.  Your opinion will be it'll work anyway, or it will be who cares. :)