Oils to use during break in

Im getting close to finish my 350 for my caprice to replace my tired 305. and Ive been wondering about break in.

Ive been told for my cam break in, to use a multi grade oil and the additive from the cam company then do the break in they describe and drain the oil. then use straight 30w oil for 50 miles and drain, then use regular oil like 10w-30 for the next 500 then im done.

Does that sound right? any one have opions or other ways to break in a engine?

I tend to be "old school" and have pretty much only used GM's EOS (Engine Oil Supplement.) I used it as a assembly lube and during break in and never experienced a problem. I know things change over the years, and different techniques come and go, just thought I'd add my :2cents:.

IMPORTANT NOTICE: If you have a Flat Tappet Cam:

Break in the cam first, before you do anything! BEFORE YOU START the engine, make sure the oil sump is filled with a CI-4/SL DIESEL OIL such as Shell Rotella-T 15w40 and pre-lube the oil system with a drill and a pre-oiler tool (these can either be bought comercially or you can fashion one out of an old distributor by grinding the teeth completely off the gear). With the valve covers off, both of them, run the pre-oiler until you see oil coming out of the rocker arms. With both valve covers still off, position the crank on #1 TDC on the harmonic balancer and look to see that at least one rocker arm on cylinder 6 is rocking - this is cylinder #1 compression (#6 is TDC with #1, alternating exhaust and compression strokes). Place your distributor in making sure that the oil pump indexes (if the distributor is flush on the intake, the oil pump is properly indexed - use a long screwdriver to reposition the oil pump driveshaft as needed), and point the rotor to what will be the #1 tower on the distributor. Make sure the plug wires run clockwise from this tower 1-8-4-3-6-5-7-2. The point here is that you want the engine to fire up immediately. Once all this is taken care of, prime the carburetor by using a diswashing liquid bottle filled with gasoline and a 5/16" rubber hose placed onto the bowl vent, place about 2 ounces of gasoline into the float bowl by squeezing the bottle. Reconnect the float bowl vent line to the vacuum diaphragm. Don't put gasoline right into the cab barrels into the intake. Pump the gas a couple of times and it should fire right up once you turn the key if all goes well - don't worry about setting the timing or anything else at this point, if it starts - run it to 2,000 RPM and let it sit there, undisturbed, for 20-30 minutes. This is CRITICAL.

Some might say this is overkill, but I really don't think it is. At this point, shut the engine down and change the oil and filter. Use the Rotella-T oil again, and keep using it as long as that engine has a flat tappet cam in it. After the oil change, you can now turn attention to making whatever adjustments you need to in order to make it run well and efficiently.

--

If you have a roller cam engine (standard on that 1987), there is no special break-in procedure for the cam as detailed above. You still need to pre-oil the engine though, so you don't have a dry start which can spin a bearing and reduce engine life by an order of magnitude. You can run whatever oil in it you want.

--

After 500 miles, you'll want to change the oil and filter again. If you used chrome-moly rings, you will want to change the oil again at the 2,000 mile mark and then resume normal 3,000 mile intervals.

IMPORTANT NOTICE: If you have a Flat Tappet Cam:

Break in the cam first, before you do anything! BEFORE YOU START the engine, make sure the oil sump is filled with a CI-4/SL DIESEL OIL such as Shell Rotella-T 15w40 and pre-lube the oil system with a drill and a pre-oiler tool (these can either be bought comercially or you can fashion one out of an old distributor by grinding the teeth completely off the gear). With the valve covers off, both of them, run the pre-oiler until you see oil coming out of the rocker arms. With both valve covers still off, position the crank on #1 TDC on the harmonic balancer and look to see that at least one rocker arm on cylinder 6 is rocking - this is cylinder #1 compression (#6 is TDC with #1, alternating exhaust and compression strokes). Place your distributor in making sure that the oil pump indexes (if the distributor is flush on the intake, the oil pump is properly indexed - use a long screwdriver to reposition the oil pump driveshaft as needed), and point the rotor to what will be the #1 tower on the distributor. Make sure the plug wires run clockwise from this tower 1-8-4-3-6-5-7-2. The point here is that you want the engine to fire up immediately. Once all this is taken care of, prime the carburetor by using a diswashing liquid bottle filled with gasoline and a 5/16" rubber hose placed onto the bowl vent, place about 2 ounces of gasoline into the float bowl by squeezing the bottle. Reconnect the float bowl vent line to the vacuum diaphragm. Don't put gasoline right into the cab barrels into the intake. Pump the gas a couple of times and it should fire right up once you turn the key if all goes well - don't worry about setting the timing or anything else at this point, if it starts - run it to 2,000 RPM and let it sit there, undisturbed, for 20-30 minutes. This is CRITICAL.

Some might say this is overkill, but I really don't think it is. At this point, shut the engine down and change the oil and filter. Use the Rotella-T oil again, and keep using it as long as that engine has a flat tappet cam in it. After the oil change, you can now turn attention to making whatever adjustments you need to in order to make it run well and efficiently.

--

If you have a roller cam engine (standard on that 1987), there is no special break-in procedure for the cam as detailed above. You still need to pre-oil the engine though, so you don't have a dry start which can spin a bearing and reduce engine life by an order of magnitude. You can run whatever oil in it you want.

--

After 500 miles, you'll want to change the oil and filter again. If you used chrome-moly rings, you will want to change the oil again at the 2,000 mile mark and then resume normal 3,000 mile intervals.

thanks silicon, I do have a flat tappet cam in it. I didnt know about priming my carb through the vent tubes, that sounds like a good idea :)

I dont have chrome moly rings, just regular moly ones. should I still drain it at 2000 miles?

there's either cast or chrome moly rings. "Moly" is short for chrome moly. Yes. The reason is that chrome moly rings take longer to break in than cast rings do - but they also last longer. ;)

thats good to hear, lol.

idk if this is just me, but all the ring sets i look at, have a moly coated top ring and a cast iron second? is that just how the moly sets are? i got my block honed for moly rings. i dont wanna waste my money and buy the wrong set, lol.

Usually it is only the top ring that is moly, the 2nd ring is cast. The oil control ring is a 3-piece affair made out of steel.