Bon Ami Works - Oil Consumption Problem Solved
 

This may surprise a few people as it runs against conventional wisdom on a number of fronts, so don't kill the messenger. I am just reporting my bonafide results.

I recently rebuilt my engine in my 68 bird convertible. It is a 468 with all high quality parts:

Forged crank and rods from Butler
Forged Arias pistons and moly rings from Butler
325 CFM KRE Aluminum Heads
Comp Hydraulic cam w/rhoads lifters - 240/246 @.050 and about .560 lift
Edelbrock RPM Manifold
Modified 800 CFM Quadrajet
Hedman 1 3/4" headers
Aluminum flywheel

Block was bored and honed with a torque plate and received first class machine work and assembly by a well respected local shop in business more than 30 years.

The engine was then taken to a local dyno operator I know where it made 538 HP at 5400 RPM and 586 lb. ft. of torque at 4000. It received at least 20 full load passes on the dyno after breaking in the cam.

I then installed it in the car. To my amazement, it initially used a quart of oil every 100 miles. I couldn't believe it. The car ran hot and showed all the signs of the engine still breaking in, even after the dyno session. I drove it about 600 miles this way. After some research, I found that the Butler valley pan was very poor in preventing oil going through the PCV system. I redesigned the system to use the driver's side valve cover. Custom baffled the valve cover and used a small air/oil separator from jegs in between the PCV and carb port. This totally eliminated oil going in through the carb PCV port.

Result: Oil consumption gradually decreased to about 1 quart every 800-900 miles. Engine gradually began running cooler and by about 3000 miles SEEMED fully broken in. I still thought the oil consumption was too high, but oh well and was resigned to living with it. Plugs still looked too dark to me but mixture readings were right were I wanted on my LM1 O2 sensor. So I thought maybe the heat range in the plug was a bit cold. I also noticed I would have oil on the threads of the plug and at the washer every time I pulled them. Again, I thought this seemed like rings haven't seated, but everything else seemed o.k. Plus, all I ever hear anyone say is that moly rings SEAT ALMOST IMMEDIATELY. As you will see this is not true, at least on my motor.

At 6000 miles I changed to Royal purple synthetic 10W-30. Same weight as the conventional oil I was using and took a trip to Indiana (I live in Florida). On this trip oil consumption went up to 1 quart every 400 miles. I was very surprised and got it out of there on the return trip, so it was in there maybe 1000 miles. After the change, the consumption did not go down and continued to use 1 quart every 400 miles. Now I was really pissed.

When I got back with the engine now having 9000 miles on it, I went through everything. Compression test WAS GREAT with 220 psi per hole and only 5 psi max difference between lowest to highest. Plugs looked too dark to me though, but not wet. Still oil on the threads and washer. I concluded that as wacked as it seemed the rings in this thing had not seated completely, or at least the oil rings hadn't. Took A VERY DEEP BREATH and decided that before pulling the engine I would try the BonAmi trick and see what happened. I took 1/2 a teaspoon full, held the engine at 2000 rpms and added it alternately to each carb bore a pinch at a time until gone. I noticed as I did this that the engine RPM actually came up slightly. When done, I took the car out ran the piss out of it with accel and decel for about 15 miles, then changed the oil and filter.

Result: Engine compression came up 3-5 psi a hole and oil consumption is COMPLETELY gone. This obviously means the rings were not seated after 9000 miles, moly or not and that the oil rings in particular were not seated at all even after 20 dyno pulls and a lot of mileage. I would also caution anyone contemplating running synthetic oil to make sure the engine is fully broken in as mine apparently went backwards and glazed the cylinder walls or something after having over 6K on it!

The good news is it runs fantastic now and appears to have suffered no ill effects from the bonami. Oil pressure has not changed and I have the bypass blocked in the filter housing which probably helped prevent any getting back into the motor after initial treatment.

Mike

Some of those "old guy" trick really do work. Congrats on your good running motor.

Stewart

What brand rings did you use? How much end gap? How much piston to wall clearance? Thanks. Jim

That was a total of 1/2 teaspoonfull of BonAmi?
Glad to hear of such success!

I've heard of this trick before and always wondered it's validity. Thanks for posting your results.

I have been having the same problem with my engine for over a year. My motor only has about 3000 miles on it since the build. I have the same issues as you exactly. I'm still going to give it some more time and more miles on the clock. I wonde if the type of hone used could cause the rings to take longer to seat? Push comes to shove I'll try the Bon Ami trick.

Is that 1/2 teaspoon Bomami into each sparkplug hole?

You're kidding, right?

I'll have to go back through my records on some of this. I want to say the rings were Sealed Power. I know they were file to fit rings. Piston to cylinder wall clearance was .0035-.004 if I remember right.

Yes, 1/2 teaspon total, not per cylinder. It doesn't take much and I thought I would start out conservatively. I got the amount from another post on the subject.

I used to use a "pinch" of BonAmi in each spark plug hole so I would say that a 1/2 of a teaspoon total shared between the 8 cylinders would be about right. Also your method would probably put less into each cylinder as you did it over time. My only thought was that it might "gum up" when it makes contact with the carb fuel and stick somewhere in the intake manifold vs get to the bores.

With my method you know at least the pinch reached each bore evenly.

Good Job!!

Tom V.

silly question , but what is bonAmi...............

It is a kitchen cleanser like ajax or comet, but finer in composition. You can get it at any grocery store for less than $1.

I really wanted to use your method as I thought it would work better but because of clearance issues I couldn't get to some of the spark plug holes very well. I think direct into the hole is a better method though. When you do it through the carb small amounts get stuck on the boosters, etc. I used carb cleaner to wash it down and get any remaining amounts into the engine.

Same thing as 20 mule team borax. In any store that has kitchen cleaning and laundry supplies.

Total Seal...
 

Total Seal sells a product called "Quickseat Dry Film Powder" they say to spread this onto the cyl walls for improved ring seating, $20.00 for a 2 gram container. Summit Racing part number, TSR-QS.

Young guy! ;):D

NO Dutch guy from europe!!!! never heard ore seen the stuff................

Isn't that what GM used on the Chevy 265 in 1955 to stop the oil burning?

OK, you have an excuse!

Stewart