Metallic sheen in engine oil - 1600 DP stock

[MarkN72]

Hi All,

Have a 1600 DP (stock) in my 72 Beetle. Expect about 50k miles since rebuilt.

Car stored for ~10 years for restoration and now second summer back on road. Cylinders/heads were off during restore and everything looked good except a pushrod slightly bent and new pushrods installed.

Engine has worked well for ~6000 miles since back on road. Oil pressure and temperature normal (gauges). Power and sounds good. Use regularly to 4500 rpm (when needed). Smiley face.

Valvolene VR1 20W50. Because the oil is quite expensive, last oil change interval was 3000 miles. The magnetic plug had a very small amount of silver metallic “paste”, looks normal to me. My concern is, the oil had a shimmer in the light caused by what appears to be very fine metal particles suspended in oil. Estimating particle size to what would form the “paste”. Presumably particles are not magnetic as are not on the magnet, but maybe magnet not 100% effective. Color of “sheen” is hard to tell, maybe silvery, maybe a bit bronze.

I thought it may be due to no oil filter. Previous oil change at 1500 mile interval also had the same sheen, which I did not get excited about as engine was a bit “new”.

I want to drive the car because I enjoy it and feel I need a bigger sign before taking the engine apart. Is the oil type and 3000 mile interval OK, or should I be doing 1500 mile interval?

Any thoughts, recommendations?

(I’ve had car since 1987. In the past I would do 1500 mile changes with Castrol GTX 20W50 which was cheap in those days. Engine has been rebuilt since then.)

Thanks a lot for any input or advice!

[Starbucket]

3000 miles is normal, microscopic particals are normal with no oil filter. If you add a spin-on filter (they sell an oil pump with a spin-on filter cover) which will let you go 5000+ miles between oil changes, it's an easy do it yourself conversion and your motor will last longer.

[MarkN72]

[Cusser]