New Engine, Dirty Oil.

[srozell]

I recently dropped a new engine in my 1980 K20. Everything seemed smooth, now at 200 KMS (120 miles) the oil is already quite dirty.

I planned on changing all the oil at about 300 miles, understanding that it would need replacement soon.

Is natural for it to look so bad so soon?

[bd]

"Dirty" is a relative term - so, what do you mean by dirty?  Is the oil dark brown and opaque?  Do you see any fine glitter?  Does it feel gritty?  Is the engine brand new or a low mileage takeout?  Provide a little more detail, please.

[srozell]

The engine is a new short-block, and the only old parts that went on were thoroughly cleaned. Looking closer, the oil looks clear, but there are lots of fine particulate in it, enough that at a glance it looks like old dirty oil. I don't see any glitter, and the oil is far from black.

[bd]

What you describe sounds normal.  Nonetheless, drain the oil into a clean pan and drag a magnet through the oil when you change it.  If there is metallic "grit" in the oil (particles large enough to feel between your fingers), post a clear pic and save the oil filter.  There will always be an initial surge of very fine particles washed out of a new engine by the initial oil fill.  Said particles are from break-in wear of the piston rings and camshaft.  That is one of the primary reasons the oil and filter are changed at low mileage the very first time.  When adding fresh oil, include an appropriate amount of GM EOS or similar ZDDP concentrate. 

[srozell]

Thanks.

I hopped in the truck and went out to get an oil filter and noticed oil leaking everywhere. Not good.

The leak was coming out of the oil filter of all places. I tightened it, started the truck, more oil poured. Great.

Popped the oil filter, and removed the adapter to find that it had cracked. My son had installed it and probably torqued it in wrong, as there were no signs of aging on the crack, and one of the nuts was barely tight at all.

$25.00 later, and a fresh oil change, everything is good again, with another opportunity to train the boy.

I looked at the oil I took out, and it really didn't look as bad in the light as I thought it was.

Thanks for the feedback.

[bd]

That typically happens when one bolt is installed and fully tightened before the other.  Aluminum thermostat housings are notorious for cracking for that very reason.  I recommend against installing a gasket between the aluminum filter adapter and block.  Make sure the sealing side of the adapter is planar then install it metal-to-metal with the bypass valve closest to the block.  Gaskets can break into pieces and push through into the lubrication stream as they become brittle with age.

[blazer74]

I like to change the oil after an initial 20-30 minute run to normal operating temp.
You can also see if something is going wrong right away from looking at the drained oil and the mag plug.

[srozell]

Thank you.

I thought it was weird that there was a gasket for this in the first place. It seemed to me at worst you'd get a minor leak within the seal of the oil filter, which seemed like a reasonably acceptable thing to me.

I was surprised that once the adapter cracked, there was enough force to push the oil filter seal out, and dump 2 quarts of oil on my driveway at idle.

I guess I can be certain my oil pump is working as intended?

[bd]

The oil pressure gauge will verify pump condition.

[srozell]

Lots of oil pressure, about 5/8th's on the needle.