Engine break in for new 350

[TruckintheBoro]

Continuing my questions from yesterday, as my mechanic installs my new (rebuilt) 350 engine into my '67 C10, a question about break in.

The guy who built my engine delivered it with oil for the break in and "primed" whatever that means (I'm a newbie). Today as my mechanic set to install the engine he said he thought he'd have it done by this afternoon and I asked if he would break it in before I picked it up and he said no, as an old engine it wouldn't need breaking in...just drive it "normal" for the first 500 miles. This was not what I've heard elsewhere. I called him back to let him know that the rebuilt motor includes a new roller camshaft and roller lifters and did that make a difference...he said no.

However I think the correct answer is to break the engine in by parking it as soon as the mechanic's got it installed and the timing right, then run it in neutral at ~2000 RPM for 20 minutes. Then change the oil and filter. Does that sound right?

[geezer#99]

If it’s a roller cam motor it still needs some rpm to properly oil the lifters and cam. They need lots of oil splash.
However is it a roller cam?
Do you have a pic or a link for the motor?

[TruckintheBoro]

It is a roller cam/lifters. Don't have a picture. Here're the specs for the new motor (below). I see that the engine build guy did make a note that the break in period I should vary the RPMs between 2000 and 2500, but the he also said I should change the oil after the first 1000 miles break-in period, but I'm guessing these may be two different "break in" periods. An initial one for like 1/2 an hour while parked for the cams, then just driving it around for a month to 1000 miles for the oil?

350 Chevy small block. 010 block with a 0.030 extra boring diameter (I think this means the cylinders were 4inches stock diameter and they’re now bored out 0.03 in wider.)
Durabond CH8 Cam Bearings
Crankshaft ground and polished
Clevite 77 Trimental Rod and main bearings
Cloyes timing set
Standard volume oil pump
Chevy 58 cc TBI (throttle body injection) heads with new valve springs, new valve seals and valves lapped
FEL-PRO PrimaTorque Head Gaskets
Elgin 1231-P Hydraulic Roller Cam
Johnson HyLift Retrofit Hydraulic Roller Lifters
7.400 inch pushrods
New Carter Fuel Pump (69 Camero)
New Airtex water pump
Hastings Moly Rings file fit 0.22 top ring
Silvolite Dish-Top Pistons 0.030
Cam button and retaining ring

[geezer#99]

I checked the cam specs on Elgin’s site.
Increased rpm isn’t critical for roller cams.
Good to increase to 2000 for 15 minutes though.
The cam lobes and piston skirts get their lubrication from
oil splash.
What is the engine builders timing recommendation?

[jimijam00]

Why not follow the engine builder's recommendation? He probably knows what he's doing. He's also the guy you'll call for a warranty claim.

[cj847]

In my experience:

A flat tappet cam needs to be run in for about 15-20 min at 2000 rpm or so. I don't think a roller cam requires this.

As far as engine break in: just drive it like your Dad would for the first 500 miles. Also, if you take a trip on the hiway, do not cruise at the same rpm for the whole trip. The engine needs to break in at various rpms from 1000 to 2500 or occasionally 3000.

After 500 miles change oil. I would recommend cutting open the oil filter to see if there are any metal flakes in it.

After that drive it like you stole it if you want to.

PS> Primed means he primed the oil pump. Not sure why he mentioned it. I ALWAYS prime the pump.

[truckster]

The main thing you're doing with a roller cam engine during break-in is bedding the rings. Drive it as you normally would, without idling for too long and without excessive RPMs, and after the first couple of hundred miles it's as broken in as it's ever going to be.

[toolboxchev]

I would most certainly dump the oil and put fresh in it after break in.

Another trick, in case of failure would be to place a large magnet on the bottom of the oil pan or on the oil filter as this willl pick up most metal shavings and prevent from doing further damage.

How large is your valve lift and will the valve train hold up to those specified on the cam? Your oiling system is a priority main and it goes to the crankshaft first. If you let the oil drain back down from the original priming you may need to do it again before start up.

Getting oil to the top end and listening for anything out of the normal engine sounds is of upmost importance on initial fire up.

Use the number 1 oil today available on the market, MOBIL 1.

[TruckintheBoro]

Thanks all for the good feedback. After I texted him for clarification, the engine builder confirmed him basically what the folks here said...drive it at a variety of RPMs and speeds without going crazy for the first while, then after 500 to 1000 miles replace the oil and filter. Much appreciated!

[bry593]

I might add, install a magnetic tip oil pan plug. Allows you to monitor the break-in process. Once broken-in, switch to synthetic. The cheap stuff from Sam's works fine....

[Myself]

I've done several builds through the years (all flat tappet) and NEVER ran one in for 20 minutes at 2000rpm. I always set them at a high idle and checked everything for leaks, then lowered the idle and went for a drive. That first drive always included several downshifts (hills work good) to allow engine braking. That will 'load' the rings and help break-in. Stay close to home and vary the throttle for 30 minutes. Come back home and check over everything. Repeat after a few hours and the engine is completely cooled down. Then drive normally for the first 500 miles. That method always worked for the old timers, and it always worked for me.

[leftybass209]

Always default to what the builder says. If he warranties it, it'll be covered.

If not, nobody who gave you a suggestion is also going to give you the money to fix it.

Breaking in a motor whether it needs to or not, is such an easy thing to do. The cost of an oil change and 20 minutes of your time you'd already be spending dialing in the motor regardless.

I don't see an avenue where it doesn't make sense either by warranty, by rule, or by piece-of-mind