I just completed a full rebuild (engine / IP / turbo / injectors) on the 3B in my BJ70. She has ~400 miles of low speed driving (commuting to work & such, typical speed range 35-45 mph with a few miles at 55-60 mph). I have not been out on the interstate so there has not been any sustained 65-70 mph operation yet.
Observations
Questions
Thanks for any insight that you can share from your experiences.
Observations
- Smooth operation with good power (per expectations for a 3B)
- Oil pressure / water temps = all show good on gauges
- Exhaust tends to remain visible after a cold start until the engine is fully warmed up (5-10 minutes of operation / 3-4 miles)
- During warm up, the visible exhaust is gray'ish in color (if the engine is not under load); black in color (when under load)
- Used ~1/2 qt of oil in ~300 miles
- Results at first refuel was 18.6 mpg (prior to rebuild performance, ~20-22 mpg was normal results)
Questions
- With new pistons/rings/sleeves, a break-in period is expected for full seating. Correct? If so what is normal? What is abnormal? [i.e., do I have a problem or continue with break-in operation tempo?]
- Are there actions and precautions that need to be taken during break-in of a 3B? [i.e., have a missed anything]
Thanks for any insight that you can share from your experiences.
