New to site with break in oil ?

[Michael Joslyn]

I have a 383 SB that now has about 2000 miles on it. The motor was run hard on a dyno with 10-40 dino. Then run about 1000 with a new batch of 10-40 dino. (run hard, lots of decceleration in gear, and WOT pulls well into top gear, 9-13 sec.)

Oil was dropped sent out to Blackstone and replaced with 15-50 M1 for another 1000. That has also been tested and is still showing high break in metals.

A leak down at this time showed 18% and 22% in 5 and 6 the rest at 10%. I wasn't impressed with these numbers so I have put 10-30 dino AND put a PCV system on the car incase it was getting a lot of crankcase pressure and a hotter thermostat.

Is there any oil that might seal the engine better that what I have chosen?

Thanks, Mike

 

[KW]

Post the Blackstone test in the used oil analysis area along with a short run down of your 383 build-up. With this info. we might be able to help.

 

[Michael Joslyn]

I'll give that a shot. Thank you

 

[jhnrckr]

Those leak down numbers are too high, it sounds like you overheated this motor. Forget oil sealing your rings and get with the engine builder, they should warranty their work.

 

[Leo]

Maybe your breakin habits had something to do with it?

 

[KW]

quote:

---

Originally posted by Leo:
Maybe your breakin habits had something to do with it?

---

I break my stuff in pretty hard too with no problems. It is possible that he broke a couple of rings putting it together or through detonation.

 

[mechtech]

First, ascertain whether the leakage is pistons or valves.

 

[Michael Joslyn]

Thanks everyone for the replys so far!

As for break in. Any race engine that I know of is going to get hammered after the cam break in, oil change, and a cool down. It is pretty hard to dyno an engine "easy". So I'm going to rule that one out.

I can't speak for a cracked ring and the engine was assembled for me by a well respected, if not egotistical and somewhat difficult, builder. I can say the air is blowing past the rings.

Motor never got hot under my care. I never saw water temps in the heads past 220.

I will tell you this. The motor was holding fine oil pressure on the dyno. after driving it about 200 miles the oil pressure began to drop sharply. Turned out the rear cam bearing wasn't installed properly and the top end was getting very weak and slow to build oil pressure. Aprox. 7 pounds at idle and 25 or 30 around 5000. We had some words and fixed the problem but I'm curious if this could be the source of the problem?

I'll see about getting my oil reports up as soon as I can.

Happy Thanksgiving!
Mike