Keep It Fresh
It's becoming a common
occurrence to purchase professionally built race engines or engine kits. To ensure
maximum service from this rather large investment let's discuss owns final
assembly initial start-up. And weekly maintenance tips. Whether you've
assembled the engine yourself. or simply uncrated it. these tips will increase
its longevity. To protect any warranty on your engine, check with the sellers
to make sure they agree with our advice.
The last place oil arrives in
any engine is the rocker arm and valve stem tip area Whoever assembles the
heads is responsible for lubricating the valve stems to ensure that they won't
seize in the guides before oil arrives on initial start-up. All cam
manufacturers sell a version of break-in lube, which they recommend that you
use to coat the lifters and cam during assembly. Most of these lubricants are
"moly"-based and work quite well. There are also several white.
petroleum-based greases that make excellent assembly lubes. Whichever you
choose. use it liberally. and get it in these places: Coat the end of each
pushrod, and if the pushrods are made from kits. put the factory made or
hardened ends into the rocker arm cup. Regardless of rocker arm type,
grease the area where the pushrods and valve stem contact it as well as the
fulcrum point. if the engine uses guide plates. lubricate them, also.
It's vital that the oil pump
be primed before the initial start-up. Wet sump systems can be primed with a
commercially available tool, or you can make a tool using an old distributor.
Have someone help you with this step. While the oil
pump is spinning, the helper should slowly turning the engine over with a big
ratchet or breaker bar (easier if all the spark plugs are removed). Continue
doing this until the oil has made its way to the top of every pushrod. Check
for oil leaks all the while and don 't feel that this procedure has to be done
non-stop. Even an expensive electric drill may not be up to the continuous load
it takes to prime the
oiling system properly So allow Me drill to rest from time
to time. To prime a dry Jump system. remove the belt from the pump and spin the
pump over with a 1/2-inch electric drill. If the pump shaft doesn’t 2 have a
bolt in kit thread one into it with a nut between the end of the shaft and the
bolt head. Lock the nut against the end of the shaft and get a 1/4 inch
drive socket that fits the bolt head. A ¼ inch drive
extension will fit the drill chuck and drive the socket to spin the pump. The
rest of the procedure is the same as for a wet sump system except that you’ll
be able to check and adjust the level of oil in the tank while you’re priming
the engine
The cooling system is the next
area in need of attention. It’s imperative that air lock be avoided. When the
radiator is lower in the chassis than the top of the engine, a surge tank
should be mounted at the highest point in the cooling system, and the engine
should be filled there. An alternate method of filling the cooling system is to
remove the upper radiator hose from the radiator. block off the outlet from
which it was removed (stuff a rag in it), and very slowly pour water into the
radiator hose as you hold it upright. Use hot tap water to fill the engine as
it will pre-heat the block and minimize the chance of excessive wear or scuffing
during initial run-in. If the engine is equipped with an electric water pump drive,
use it to circulate the water through system. Check for leaks then remember
to re-check the water level before starting the engine. Make sure that the
floor under the engine is very clean or lay some dean cardboard under the
engine to make it easier to spot leaks. Turn fuel pump on and off for a few seconds
at a time to allow the carburetor float bowls to fill slowly to avoid banging
the needles into the seats.
Check for fuel leaks and adjust fuel pressure. Be certain to
look into each throttle bore to ensure that fuel isn't dripping into the
engine. Stuff some clean rags around the accelerator pump discharge nozzles~ to
catch the fuel and work the pump arms one-at-a-time with your fingers until the
accelerator pump diaphragms are primed.
Remove the rags and the engine will be ready to start. For
the initial run-in. use spark plugs that are one heat range hotter than the
racing plugs and pre-set the ignition timing a few degrees advanced of what the
race setting will be for less combustion chamber heat.
When you start your
engine for the first time, five to ten minutes at 2000 to 4000 RPM will allow everything
to break-in property. When you have a high-performance street engine with a new
cam and lifters, you may want to run it even longer.
Keep an eye on oil pressure and water temperature so that
you can shut the engine down if either reading becomes excessive.
If the car is equipped with a
manual transmission be certain not to hold the clutch in while starting the
engine. This puts pressure on the crank thrust bearing and can cause premature or
excessive bearing wear before you get out of the shop.
Jack up the rear of
the car and leave the transmission in neutral while starting the engine.
Warm-up the driveline while the engine is running. This is a good idea before
making your first run down the track. And especially important in cold
weather.
Make sure that the
car is securely resting on jack stands and support it under the rear axle
housing so that the driveshaft and u-joint angles are similar to actual racing
conditions.
It's very important with wet sump oiling that the rear of
the car is not raised a great deal higher than the front as it could cause the
oil to move away from the pickup and damage the engine.
After the engine has been
broken in there are certain procedures to follow religiously after an initial start-up
and after every race.
Turn off the electric
pumps while the engine is still running to allow the fuel level in the bowls to
run down slightly. You don't want to empty the bowls completely. Just drop the
level enough so that fuel doesn't slosh out when the car is being trailered.
Check for oil or water leaks. Take a leakdown test of the cylinder and record
the results. including the engine temperature. This makes It much, easier to
keep track of the engine's condition from week to week and to know when it's
time for a freshen up.
Readjust the valve lash while
the engine is still hot. Then drain the oil and remove the filter. Examine the
oil then cut open the oil filter and inspect it carefully. A new engine may
deposit a lot of scary looking stuff in the oil and filter. Have someone with
prior experience inspect them to show you what you need to be concerned about
and what you can ignore. With an aluminum rod engine there may be a lot of
metal in the oil in the first week but
noticeably less thereafter.
Drain the cooling system or at
least relieve the pressure in the system. This will alleviate water
leakage problems caused by min areas or pin holes in the cylinder heads or pan
rail
areas.
By now the engine will have cooled dorm enough to perform
the following step.
Remove the spark
plugs one at it time and spray WD40 inside the cylinder. Give each bore a 3 or
5 second blast and be careful that the extension tube from the WD-40 can
doesn't fly into the cylinder.
This will minimize surface rust on the cylinder walls and valve
seats which accumulates between races, thereby extending ring life.
The longer the plugs stay in the engine the easier they are
to read. It’s important to always degree your spark plugs even if there isn't a
piston to plug clearance problem. Degreeing the spark plugs ensures that they
see similar heat and combustion conditions from cylinder to cylinder
If you want to re-torque your cylinder
heads. wait until the engine has cooled down completely and follow the
recommended sequence. If you re- Torque the heads while the engine is still hot,
you may over torque them.
Although the subject of this
month's column was aimed towards longevity. I'd like to leave you with a tip
that's good for a few horsepower. All wedge head combinations (except~ nitrous
and blower engines). Especially those with big-dome pistons. will run better
with "side-gapped" spark plugs. The side gap allows you to use projected
tip plugs in engines where they wouldn't ordinarily clear. and shortening the
ground electrode minimizes the way it's affected by heat. Bill Jenkins showed me this about 28 years ago
and it still works today. To make a set of side-gapped" plugs you must
make a tool to cut the ground electrode.
Use a pair d diagonal
or side cutting pliers and grind down the front as shown in the pictures. This
allows you to shorten the round electrode without damaging the insulator. Cut
the electrode on in the middle of the bend. The end of the electrode will be
pointy where it was cut so it must be filed flat.
Clamp the plug into a vise and with a small flat file, file
flat and then break the edges. Being careful not to damage the center electrode.
Bend the ground electrode over towards the side of the center electrode and set
your gap with a round gauge. Use caution as the shortened ground electrode doesn’t
bend.
