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New engines burning oil, Too much fuel?

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Jerry

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We have two rebuilt engines with 200-500 miles on each. They both went through 2 quarts of oil in the breakin miles. Evidence at the plugs indicates that they are running rich. Would rich mixture wash the oil off the cylinder walls and cause it to be burned? There was some during shifting. Any other ideas? One car is TR4, the other is a MGB. Jerry
 
It depends how rich. If, for example, the cars start without using the choke, then that is too rich and could be a problem. Most likely, the rings have not seated, and that is causing the oil burning. I would wait a little longer and see what develops.
 
Burning rich should not be a reason for and engine to burn 2 quarts in 200 - 500 miles. I'd say the rings didn't seat.
 
Hope you used a tree hone or something to scuff the walls of the cylinders, very important!

Wayne
 
Also -- what sort of driving did you do during the break-in?

Possibly different schools of thought here but I have always worked new rings by hard acceleration and abrupt backing off.
 
That's how I was told/taught to break-in rings. Vary piston speed alot. No long constant piston speed drives. Also told to not load the engine: uphill, high gear, low rpms. My oil level has gone down <1/8" on the dipstick. I have 960 miles on a fresh rebuild. Hope to do the 1000 mile oil change this weekend...the wix filter, VR1 20-50, and VDDP plus is waiting.

Any chance you're leaking. 2 quarts in short order should be visible in the exhaust. IMO.

Good Luck,
Tim
 
Actually, to break in rings you have to load them. The usual method is to use third gear and accelerate under full throttle from about 30 to 60 mph. Then let off the throttle and let the intake vacuum pull the oil back up and cool them as you slow back down to about 30. Repeat a good 10 times.

Too rich normally washes the oil and fuel down, which increases the oil level instead of reducing it.

Did you do anything different, like adding a PCV system?
 
No PVC system. But Both Drivers are mild drivers. So I will tell them to push it a little more. Jerry
 
Are you using break-in oil? I'm not exactly sure what all's different about it except that it contains a lot of zinc, which is necessary for flat-tappet engines. The machine shop that worked on my engine swore by it.
 
You can also use the old tried and true application of 'Bonn-Ami' through the spark plug holes. ISTR about a tea spoon per cylinder. Others may remember this treatment from back in the day.
 
Jerry, What brand are the rings? Are they chrome rings? chrome rings take longer to break in. Were the cylinders honed with a cross hatch pattern in them, consistent 45 degree angle on the cross hatch? PJ
 
Before you do all this I would highly recommend you buy an inexpensive vacuum gauge at Northern Tools or Harbor Freight, and verify rings are in fact a problem
 
The rings were from MOSS along with new cylinder sleeves and pistons. All new in the box. No I did not hone the cylinders prior to installation. I never have before with new sleeves. So MOSS sells iron rings, I think. Jerry
 
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