Oil quiz, NOT the "dreaded oil question"

baddean · Post by **baddean** » Sun Nov 11, 2007 5:10 pm

Installed an upgraded alternator rotor on my '73 750GT tonight and after draining the oil I found flecks of gold colored, non magnetic, particles in the drain pan.
My question to the masses that are in the know is, what is the most likely source of the flecks?
I'm assuming that they are from a bronze bush of some sort.
There were no particles on the oil filter screen nor were there any in the alternator cavity.
I'm scratching my head on this one. A couple of bottles of beer didn't turn a light on either.
Thanks, Dean

Den · Post by **Den** » Sun Nov 11, 2007 6:50 pm

Let me make sure I understand. Do you mean to say that PRIOR to starting the task of installing the rotor you
drained the oil and saw the gold flecks? I want to be able to eliminate the new rotor from the list of possibilities.
Right off the top of my head I'm thinking that unscrewing an oil drain
filter/screen that was slightly cross-threaded could allow bits of the thread from the brass drain to be washed
out and none found elsewhere.

baddean · Post by **baddean** » Sun Nov 11, 2007 8:48 pm

Hi Den,
Thanks for the reply. Yes, prior to working on the rotor I drained the oil and found these. The filter drain plug was easily removed by hand once it was initially loosened and easily reinserted.
Dean

Den · Post by **Den** » Sun Nov 11, 2007 9:13 pm

These are all the brass/bronze bushes I could think of:

inside the 35 tooth kickstart gear

underneath the 34 tooth 1st gear

inside the lefthand case supporting the end of the kickstart shaft

in the oil pump cover

inside each of the 4 rocker arms

rod's small end bushings

oil filler plug

oil drain/screen plug

timing plug on clutch sidecover

.

baddean · Post by **baddean** » Mon Nov 12, 2007 3:41 pm

Hey Den,
Thanks for the heads up. With the amount of this debris in the pan I'm thinking it has to be something that's rotating while the engine is running.
Rocker shaft bushes come to mind first because they are poorly oiled to begin with.
First gear bush, maybe.
Rod small ends, also maybe.
Can the rocker bushes be replaced with the heads in place and the engine in the frame?
I'm still baffled as to why there was no debris on or in the oil filter screen or in the alternator cavity.
There is a fair amount of this debris in the pan.
Thanks again, Dean

Den · Post by **Den** » Mon Nov 12, 2007 6:34 pm

.
"Can the rocker bushes be replaced with the heads in
place and the engine in the frame?"

.....Yes.

"I'm still baffled as to why there was no debris on or in
the oil filter screen or in the alternator cavity."

.....The debris is heavy, it goes to the bottom.

.