Siegfried; you ask about torque when using silicon glues. Torque remains
unchanged from what would be correct with a fiber gasket. Generally the
requirement is nothing more than to assure a firm "clamping action" upon
the two surfaces being joined. Obviously there is also a limit to the
amount a certain bolt or stud will sustain before breaking.
I assume you know about SAE std. bolt and nut markings which indicate the
tensile strength of the item. It runs from unmarked (uncontrolled and
unknown strength) up to grade 8 supertanium used in aircraft and other
vehicular applications where a max torque must be applied, such as might be
found in steering and suspension units, bearing caps etc.
Once you have snapped off enough 1/4" side plate and oil pan bolts, you get
a feel for what they will stand...and it's not much torque but is
sufficient to clamp the parts OK.
The shop manual provides torque specs on major units but some, like rocker
arm posts and miscl. pieces you just have to have the feel.
Working on anything made of aluminum (heads) requires real care not to
strip the threads. Helicoil fixes everything just fine and is also cheap.
Back to your oil pan.......lay it on a smooth cement surface or any other
hard level surface and use a heavy hammer to pound a flat hunk of steel
around the gasket edge area. Flatten out ALL those holes which have a
trace of raised metal around the hole. It is NOT required that the entire
pan be in a perfect true flat plane. What we need is that the gasket
surface be level so that when bolted up it will make 100% contact or a well
as possible. The beauty of the silicon is that allows quite a lot of waave
and ripple in the gasket surface and fills the voids nicely.
DO NOT over apply glue as we don't want it to ooze into the inside of the
pan where it may eventually break off and circulate into the engine
passageways causing a clog or problem. With a well cleaned pan, apply the
glue about 1/16" high and about 3/8" wide ribbon all around each hole and
straight portion. Remove glue where you see too much applied. Work slow as
this stuf will not harden up for 30-40 minutes and allows you lots of time
to move things around and have a clean job.
The side plate (tappet plate) is one place where Rootes all leak and where
silicon make a perfect dry engine area.
The front and rear main bearing caps have that cork seal and this is
another place where you can get a perfect dry engine.
Cut the corks to just stand proud (limey term for sticking up a tad), give
each cork a hand job coat of silicon on ALL it's surfaces, press into
position and apply a 1/16" thick coat to the entire cork and extend that
ribbon onto the engine block a bit. Bring the oil pan into position slowly
with ONE movement (no swimming around please). Install one center area
bolt on each side semi tight to hold the pan from movement. Then install
all bolts (except those holding the twin brace rods and bring them up to
desired torque as determined when you feel them harden up when metal to
metal clamping is obtained. Lastly install the braces and their bolts.
Wipe off any squeezing seen externally...and say a prayer you have not
gotten some dripping inside! Silicon glues are totally reliable and
solve sealant jobs everywhere except on head gasket and exhaust surfaces.
------------------------------
Chris; worn (used) lifters normally would be best replaced into original
bores but years ago I quit doing this because measurement to 4 deimal
places showed NO wear on bore sides or lifter sides. Of course there could
be exceptions so inspection is needed . What I do is clean the used lifter,
inspect for base chipping which would not likely clean up properly and
reject any having a hunk missing or damage of some sort.
I reface the base and super finish with a very fine grit stone of about
#800 to 100- grit. I have installed stock engine with refinished lifters
having the coarser finish just as the valve grinder gave the base. They
never fail or cause cam problems so perhaps my extra effort at a super fine
finish is a waste of time. We do tend to be fussy-fussy on race engines
and of course the cost is not considered.
Then, I go to the engine block which is of course 100% clean, and I push
each lifter into ONE block hole to see that they all fit that hole with an
even and equal amount of drag. Then I take one lifter and push into all 12
holes....again looking for an even drag in all holes. I have NEVER found a
block hole or lifter which was not just perfectly satisfactory (but who
knows??? could happen, hence these simple tests which take only a few minutes).
WARNING... when installing lifters and cam always always always apply
plenty of engine assembly grease to lobes and lifter bases. It will be some
time before oil pressure gets up and does it's job. Serious scoring can
happen if just plain oil is used. Also use this stuff in rods and main
bearings for the same reasons.
--------------------
To ALL readers; I assume the old time advice of using non-detrgent oil in
the engine has long vanished but......just in case....USE ONLY the highest
detergent oil rated API service SH (current) or SG (previous rating).
Never ever use motor oil rated SA,SB,SC as these simply have not enough
protective chemicals to do the job.
Also...NO oil additives are to be added to your SG or SH motor oil. None
are needed and usually none are worth a damn ! Stop and think???? If some
additive could really doe what they claim, it would be sold by GM or Ford
or some biggy and would be recommended by major vehicle mfr's.
All modern engines from say 1937 onwards, have been designed with NO
borderline lubrication spots inside the engine.! All that each engine
requires is the proper viscosity and proper API grade of clean oil.
Several years ago at an SAE convention, the chief engineer for GM finished
his speech and asked for questions from the audience. Some wise guy asked
if GM cars were as durable as others???
The answer was as follows:
"Gentlemen, assume you take one of each of the worlds cars, install a robot
driver and line them up on a 20 mile circle at Bonnaville salt Flats.
Start the line moving at high and medium speeds which are not abusive
speeds. When necessary, stop the line and service each car properly, and
restart the line.
As we all know, these cars are wearing OUT and will eventually come to a
stop of their own volition! When that happens...the line of cars will be
still quite straight ! All the cars have equal durability when serviced
and driven as intended. When the Rolls finally breaks down and stops, so
does the Chevy, Ford, Toyota , Mercedes etc. etc. We claim no superiority
in the areas of life span, machining qualities and other areas related to
long life. We do claim superiority in certain areas of efficiency and
performance for certain of our vehicles, just as our fellow mfr's can claim
for certain of their vehicles. Does that answer you question sir? " Dead
silence in Cobo Hall, then massive applause.
---------------------
Dick T.
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