New Motor

[tikihut]

Im new to the 911 and Looking for some input on break-in procedures for a new motor. Type/weight/amount. 72 911T/ 76 2.7 S motor ?

[GH85Carrera]

Talk to whoever built the engine and find out what they recommend. Usually driving it, and varying the RPMs from idle up to 4,500 RPM max and under various loads like hills in various gear and RPM.

[911 SLANT]

I ran VR-20/50 high Zinc Racing. Was told for break in period. You also can keep using as a regular oil. Also upon first start up, do not Idle for to long. You will glaze up cylinders. You have to drive to seat rings. I had this problem on my first 2.7 rebuilt. #5 cylinder would not seat. Finally the ring broke. That why I built the 2.8

[lvporschepilot]

I've seen several people recommend a non-detergent straight 40 weight until the rings are seated. I believe several oil manufacturers such as Gibbs make such a 'break in' oil as well. I personally run a non-synthetic 20/50 and immediately drive the car, varying rpms. Specifically, get the engine fully warm, accelerate in 2nd gear from around 2000-2500rpm to 5-6k rpm, then slow while in gear back down to 2000-2500. Do this a number of times, then drive on the freeway for a hundred miles or so making sure to vary rpm and continuing to slow in gear. Slowing while in gear creates a vacuum pushing the rings against the cylinder walls for better break in. Change break-in oil after confirmed rings have seated.

[tikihut]

Good info. Thanks!

[darrin]

you should also do another valve adjustment/oil change 1,000 miles after the rings seat