350 break in question - Lateral-g Forums

Jr · #1 06-27-2008, 09:28 AM

Hi guys,
I just put in a new 4 bolt main 350ci motor in the truck. So far...I have really high oil pressure. How should I break it in?

David

chevyIIpost · #2 06-27-2008, 09:38 AM

What is your oil preasure? What type of cam shaft, flat or roller? Crate engine or fresh rebuild? If it is a crate motor call the supplier and do as they say. Where is your oil preasure gauge attched to the engine and have you verified the accuracy of the gauge?

Jr · #3 06-27-2008, 10:09 AM

The motor is a fresh rebuild, I guess. I got the long block from chevy. The oil pressure needle is 3-4mm from the H. I will find out more information...My bad for not having the information

**Ummgawa** · #4 06-27-2008, 05:53 PM

Quote:

Originally Posted by DJW32

The motor is a fresh rebuild, I guess. I got the long block from chevy. The oil pressure needle is 3-4mm from the H. I will find out more information...My bad for not having the information

Did you put a hi-volume Oil pump in the motor?

**camcojb** · #5 06-27-2008, 06:01 PM

first thing, get a mechanical gauge that reads in true psi, and see where you are. There may not even be an issue, but with any oil pressure delima I always start by verifying with another gauge. Since you're using one that doesn't even read psi, you definitely need to start there.

Jody

Jr · #6 06-30-2008, 01:55 PM

Quote:

Originally Posted by Ummgawa

Did you put a hi-volume Oil pump in the motor?

I don't think so.

Jr · #7 06-30-2008, 01:56 PM

Quote:

Originally Posted by camcojb

first thing, get a mechanical gauge that reads in true psi, and see where you are. There may not even be an issue, but with any oil pressure delima I always start by verifying with another gauge. Since you're using one that doesn't even read psi, you definitely need to start there.

Jody

I will get a mechanical gauge on it.

Jr · #8 06-30-2008, 01:57 PM

The motor is not rebuilt. The motor is brand new from chevy. It is flat,8.5:1 comp. motor.

chevyIIpost · #9 06-30-2008, 05:06 PM

Did the oil pump and oil pan come on the motor? Am I correct that you stated this is a new chevrolet short block with a flat tappet cam? If yes to both of these and when you get a verified mechanical oil presure gauge attached to the oil port by the distributor or above the oil filter then this is my check list of prestart items. Since you have stated that you think the preasure is high I am guessing you have started the engine at least once.

**I set dist timing to 12 degree static or more.
**Have timing light and oil gauge and temp gauge attached and ready
**Place a big electric cooling fan in front of radiator
**Verify all fluid levels...oil,water,trans,power steering have additional fluids ready
**I drill two 1/8 inch holes in t-stat to make certain I don't have air trapped
**What oil is in engine? With a flat tappet cam I like Rotella and break in additive to protect the cam.
**Have the fuel system primed or carb float bowl full. You do not want to crank the engine a bunch to start it.
**If it was a short block are the valves all adjusted correctly??????? If your not certain don't start the engine until you are certain!!! If your not certain how to adjust just ask how and one of us will be happy to explain. Was the correct cam assembly lube used on the cam during assembly?

I would start and run the engine at a minimum of 1500rpm. Verify no leaks, misses or bad noises and that you have more than 30 psi of oil presure with a steady needle. Verify that you have more than 12 degrees of timming at 1500rpm. Do all this quickly then raise engine speed to 2000 rpm and re-check timming, no leaks, or bad noises. I would like to see over 20 degrees at 2000 rpm. If the timing is retarded it will run hot. keep an eye on temp and oil preasure and check for leaks. You are breaking in the flat tappet cam using the engine speed to splash and spray plenty of oil on the lobes and lifters. Do not idle the engine!
Run it for at least 20 minutes. during that 20 minutes I will vary the speed front 1800 to 2400 prm every 5 minutes. Even after this break in period I try to keep the idle time to a minimum with an flat tappet cam until I have some break in miles on the motor.

This motor has a mild cam and depending on the valve springs it should not be any problems during break in. 60 or 70 psi cold oil presure at 2000 rpm would not worry me. If the presure is above this I would be nervous. The lifters should not be making any ticking noises while running. These preasure numbers are assuming a standard volume oil pump. IMO a high volume pump on any small block is a mistake and a waste of rear wheel horse power.