Please help diagnose my sound.

This has to be something pretty bad.

I have a freshly rebuilt, bored, TBI 350.

During the intial start up and cam break in I boiled over the coolant, but shut the car down quickly.

Now (after fixing the cooling problem) when I start the engine it will run great for about 20-40 seconds, then a very loud metal on metal rubbing/moaning sounds come from the engine. Of course I immediately shut it down.

I can restart the engine and it will repeat, run great 20 seconds, then same thing. The sound is horrible, vibrates the truck.

I have had very high oil pressure from the beginning (gauge ends at 60 psi and gauge stays pegged) but people have said that isn't uncommon on a brand-new rebuild. I'm not the person who had the engine rebuilt so I don't know if a hi-volume oil pump was used.

Something is clearly heating up in the engine and then losing tolerance and rubbing.

I assumed a spun bearing, but after reading a bit sounds like spun bearing makes clicking noises and cuases low oil pressure? This is definitly not clicking and I definitly don't have low oil pressure.

What could this be? Does my high oil pressure mean my oil is blocked from getting somewhere maybe a bearing, but what would be expanding so much to be stopping the engine?

The engine must be trashed, becuase the first time I ran the engine I made it through 10 minutes of the cam break-in before it over heated so if something was starved for oil, it is ruined by now.

Any ideas?

Thanks 89 IROC,

Thanks for the advice, I'm thinking this might be a good opportunity for me to tear down my first engine and look at these things.

However my motivation is wearing thin right now. My whole goal was to have my truck up and running before winter arrived, especially since it is in my driveway (not a heated garage!)

Tonight it is supposed to get down to 17 degrees and we're just at the end of fall. The truck may just end up sititng in my driveway until next spring. A wrench feels pretty uncomfortable in your hand this time of year out in the driveway.

I will try and get the oil check done and cut the filter before I quit for the year.

I realize that wrenches seem cold this time of year, but if you have room in the garage, you could get the engine out of the vehicle,and on a stand, get a small electric, kerosene, or propane heater. And have a semi heated shop. That being said if you live with a woman be it mother, g/f, wife, etc. It is my experience that the mess this makes inside your home is not worth the grief you will endure, because you will never get everything clean.

Just my .02

You are a smart man 89 IROC! They women hate it, I notice during "car" season, my front door and bathroom and lightswitches between front door and bathroom, all begin to get a greasy coating with smudged finger prints.

I accidentally got POR15 on my bathroom light and inside my new sink

I'm not as smart as I sound, just well trained. My g/f hates grease, gas, etc............. Too bad I'm a technician, guess she'll have to get over it

My roommate did a rebuild in the garage and we had grease all over the door coming into the house. A bright white door, and it was all over it on both sides.

I saw a can of that Permatex, that white stuff that costs like $1 by the sink. I got to thinking and got some paper towels and smeared some on the door and the grease came right off.

We are talking 20 year old nasty black stuff. The door smells like Permatex for a few days and then its gone. It works on your clothes too.