It's been couple of years since I've started a new engine. The last time I was told to fire it up,then rev it up to 1500- 2000 RPS for 20 min. to breakin the cam. Is this still the way? The paper work with the engine never said anything. It's a GM crate engine. I put the Comp Cam oil to protect the cam lobs.Just askin, Thanks aor any help.
If you have a flat tappet cam then that's the correct procedure. If its a roller you don't need to keep the RPMs up to that level.
Try to have the carb bowl filled and timing close so it will start as soon as possible. I like to rev mine from 1500 to 3000 alternating RPM the entire 30 minutes or more. You cannot be too careful.
You can also do the break in time in spurts if the car starts getting hot. As long as you put a half hour or so on it you can do it in 10 minute segments. A big fan in front of the radiator helps a lot. After the break in period drain the oil, add new oil and filter with more cam break in lube, and you should be good to start driving it. Don
Prime the oil pump for a good long while before start up, if you haven't already. Also good to have an extra set of eyes looking for leaks or other hazards. Good luck!
Well, flat tappet lifters can wipe a cam lobe if there is any metal to metal contact for even a short period of time. This process helps prevent this and hardens the surfaces properly.
Even if the engine has been run to break in the cam, it doesn't hurt to do it again and know its done right. It won't hurt anything to do it but it could hurt not to do it. I asked this question last time I bought a new car and they said they do it at the factory. In retrospect, that was a salesman, he probably just made that up.
FAB32, It's in a 33 chevy sedan of my buddys, He cracked the block ,out of water, on the way home from Des Moines Goodguys show a week a go.GM crate motor, and I told him I'd help put it in. And we did prime the oil pump. It should be ready to go as soon as the new radiator gets here ..Thanks for the info everyone.
I would gut out an old thermostat and do the brake in as recomended that less chance of over heating.
Before the 1990's all USA OHV engines had flat tappet cams.Did the factory break them in? I doubt it.Now many of those engines had really mild cams but still.... Yes, I do run flat tappet engines at 2000 rpm for 20 minutes... or drive it around because it's more fun.
Little update, Started the engine today. Only had 2 plugwires turned around(2+4) otherwise ran great run it 10 mins at 1500rpm, the took it for a drive.Ever thing seems good. Set the timing at 8,adjusted the idle jets. Told him to drive it watch for leaks or noise .See how it goes. Thanks for all the info.