We have been building TR-3,4, MBG, Lotus, Ford, etc. engines as part of our
business at The Engine Room here in Santa Cruz since 1971. In newly rebored
or otherwise very round (unworn ) cyinders, we have always used chrome top
compression rings. We have never had a compression ring seating problem! The
only ring seating problems we have had were with the cast iron oil rings
that come on many english pistons . We have for many years now used
Hastings or Sealed Power (now Federal Mogul) 3 piece oil rings and have
never had any oil consumption problems with these rings.
The Preparation we use is when boriing a cylinder, we leave .003" to
hone the cylinder to size. The last hone is done with a Sunnen 300 grit
stone being carefull to leave the hone marks at 30 degrees up and down from
horizontal. After this, we final hone in a bath of solvent or honing oil
with a "Brush Research" "dingel ball" hone. These are available in different
grits and different sizes depending on the exact ring type and bore size.
Again we make sure there is a 30 degree angle to the horizontal to the
honning marks. Finally we clean the cylinders using automatic transmission
fluid, wiping the cylider with a soft white rag and lots of atf until there
is no more grey color comming off of the wall. At that point the pistons are
ready to install.
We lubricate the pistons and rings liberally with an assembly fluid made
up of Kendall GT-1 40 SAE and Molybdinum di Sulfide in an oil base (ie MR.
Moly Break in Lube or a similare product) and assemble the engine.
Before start up, we crank up oil pressure with no plugs in the engine,
after getting oil pressure, we fire up the engine and immediately bring it
up to about 2,000 rpm and run it for about 10 minutes to break in the cam
and lifters. We then shut the engine down, retorque the head & manifolds &
adjust the valves. (This is with a TR that has an iron head). Then the
engine is put under about 30 - 40 ft. lbs. of load (if on a dyno) for about
30 to 45 minutes with the speed beginniing at around 3000-3500 rpm and
gradually increased to 4500 rpm or so. The engine is then ready to load.
If the engine is not going to be run on a dyno, but is going to be used
on the road, then it is taken out and driven. If it is a road engine, we
load it at WOT fron 2500 rpm up to 4,000 rpm 10 times in succession allowing
the engine to coast down from 4,000 to 2500 in gear each time. This creates
a high vacuum in the cylinder and pulls oil up into the ring area to cool
the rings between each time the load is applied. This process seats the
rings. The car should now be driven for the next 500 miles with the engine
speed varying as much as possible (like continuous miles on curvy mountain
roads) gradually using more rpm up to whatever your rev limit is to be.
If the car is a race car, then out onto the track. A couple of laps
using 5,000 as a rev limit, then a couple of laps at 5500, and so on up the
rev limit you are going to use. Then readjust the valves to your hot
setting. Change the oil filter and oil after the initial track session.
According to the ring manufacturers, the rings are "lapped in " during
the manufacturing process and so they claim there is nothing to be gained by
more lapping.
Regards,
Greg Solow
Sent: Saturday, February 14, 2004 9:07 PM
Subject: RE: bon ami
> Justin wrote (with major snippage) :
> > Bon Ami Cleanser
> > Bon Ami contains the effective yet gentle abrasives feldspar and
> > calcite.
>
> > Bon Ami Cleaning Cake and Bon Ami Cleaning Powder
> > Both contain gentle feldspar abrasive for polishing and soap
> > for cleaning all hard surfaces. Use to defog windows and mirrors. NASA
> > even used Cleaning Powder to clean the windows on Skylab. Stock
> > up and save!
>
> > So the later product is the cleanser, which doesn't contain "soap", but
> > does contain "detergent and bleach". I purchached a can of this today,
> > and it warns that it contains "calcium carbonate" which I believe is a
> > detergent.
>
> I forgot to address this point ... Calcium carbonate is not a detergent
> (which is a good thing since it's the major ingredient in Tums), it's also
> known as Calcite or limestone. It's the abrasive in Bon Ami Cleanser (but
> not in Bon Ami cleaning powder) that is harsh enough to scratch glass.
Both
> have feldspar (which is actually a generic name for a group of very soft
> minerals), but only the cleanser has calcite.
>
> And I assume we're all clear that dumping this stuff down the intake is
not
> a normal thing to do, rather it's a last ditch effort before tearing the
> engine down again.
>
> Randall
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