20 CISON LS V8 (LS-52) Practical Build Tips from Expert Jamie RCBlock | Stirlingkit

Super important: check all oil and cooling passages. When looking at the oil delivery holes, they should all be the same size, as this is a pressurized oil system. Use a thin solid wire to poke through blocked holes.

Tip: a blockage will make the hole look smaller than the rest.

Stirlingkit Note: Use wire thinner than the hole and only push out debris. Don't enlarge or ream the passage. After clearing, blow the passages out with compressed air.

The water and oil pumps use brass gears. Take a flat piece of glass or a mirror with 2000-grit wet/dry sandpaper and wet-lap the brass gears.

Why it matters: Polished gear faces are more efficient and cause less wear to the pump housing than unfinished gear faces.

Lap the 3 top faces of the block and the mating faces of the cylinder heads. Wet-lap using 2000-grit wet/dry sandpaper on a 12×12 glass tile.

The goal here is:

1. To ensure flatness of critical sealing surfaces.
2. To make it easier to remove the cylinder heads down the road without damaging the head gaskets.

Stirlingkit Note: Lapping tips for tips 2 and 3: keep the sandpaper wet, use light, even pressure and a figure-8 motion, and rotate the part every few passes. Stop as soon as the whole face shows an even finish; the goal is flatness, not removing material.

After going through the first 3 tips, it is time to wash all parts thoroughly with dish soap and a toothbrush, rinse thoroughly with water, then blow dry.

Use caution not to wet any bearings. Use a rag to clean steel parts, and re-oil the steel parts right away to help prevent rust.

Stirlingkit Note: Blow compressed air through every oil and coolant passage after washing, so no water or soap stays inside the block.

File a 45° bevel in the top edge of the rocker arm adjustment screws. The cylinder heads are tight on space, and the bevel will prevent the rocker arm adjustment capscrew heads from rubbing or even binding against the cylinder head walls.

Why it matters: It allows the rocker arm to go through its full motion without getting stuck in the open position.

Installing the crankshaft is extremely important. Take your time and be patient. The little brass inserts can be a little tricky to install, but they must sit flat and even in the center support. Number each support before removing it.

Sometimes it is just easier to show you, so here is my detailed crankshaft install video:

The Cison LS V8 has a sophisticated oil system. After installing the crankshaft, take a syringe with oil and push it through the oil intake to test that oil is flowing to the right places through the crankshaft.

Don't stop there, though. Double-check after the pistons are installed, and check oil flow again after the camshaft is installed.

The LS oil system is very efficient. If oil has trouble flowing, there may be a blockage, so investigate closer.

Use Ultra Black to secure the ignition arrow in place:

1. Rotate the engine so the No. 1 cylinder is at TDC.
2. Put the ignition arrow in place, put the crankshaft pulley on and temporarily lock it in place.
3. Position the ignition arrow on 0° and outline it with an ultra-fine Sharpie.
4. Take everything off, add Ultra Black to the ignition arrow and align it with the outline. Use tape in a few places to hold it until dry.
5. When dry, dry-fit the crankshaft pulley, confirm the No. 1 cylinder is at TDC and the ignition arrow reads 0°. Now the ignition arrow is set in place.

Stirlingkit Note: Let the Ultra Black cure fully before running the engine. Check the cure time on the tube (full cure is typically around 24 hours).

Finding it difficult to keep O-rings in place during assembly? Use a small flathead screwdriver to put tiny, Nerds-candy-sized dabs of red grease in the O-ring groove. Usually 3 spots is enough to keep most O-rings in place.

Stirlingkit Note: Use a grease that is safe for rubber O-rings, and only a tiny amount. Too much grease can squeeze out and block small oil passages.

The Hall sensor board is held in place with only one capscrew, so use a machined flat washer between the capscrew and the Hall sensor board to help secure the Hall sensor perpendicular to the crankshaft.

When you are happy with the Hall sensor ignition timing position, take it off, apply Ultra Black around the inner diameter of the Hall sensor board and reinstall.

Why it matters: The Ultra Black helps secure the Hall sensor to the engine and isolates it from engine vibration.

Stirlingkit Note: Moving the Hall sensor changes ignition timing. In his coil test, Jamie kept it centered for consistent results. The Hall sensor is also sensitive to over-voltage; see why Jamie never runs the MCU above 12V.

I've removed the center valley plate several times, and I know I will want to take it off again in the future without damaging the gasket. So glue gasket #98 in place on center valley plate #77 with Ultra Black, then temporarily install it on the engine finger-tight (don't torque) while it dries.

Now you can remove the center valley plate as often as you want without damaging the gasket.

The starter assembly gear mesh engagement is very important. Double-check the gear mesh when installing the starter assembly, then check it again after a handful of starts. If the gear mesh feels loose, evaluate and readjust if necessary.

After approximately 20 starts the gears will have fully seated, so always check the gear mesh at first until no more adjustment is required.

Stirlingkit Note: A grinding or clicking noise when starting is a sign the gear mesh needs adjusting. Stop and check it before trying again.

Oil can splash the ignition coil board through 2 holes on the backside. Use orange copper to seal the 2 holes behind the ignition coils on both valve covers.

Stirlingkit Note: Jamie means a high-temperature copper RTV sealant. Sealing these holes keeps oil off the ignition electronics.

The valve covers have 2 exposed screw holes below the ignition coils. Stuff breathable, fuel-safe foam into these holes.

Why it matters: The foam acts as a filter: it allows added crankcase ventilation while keeping dust out and oil splatter in.

Stirlingkit Note: Use foam made for fuel and oil, such as RC air filter foam. Ordinary craft foam can break down when it gets oily.

Each spark plug wire has its own resistor. Cut one end to 3/8" long and turn it while inserting it into the spark plug wire. On the other end, make a small loop and trim the excess wire.

Why it matters: This keeps the resistor in place and gives better contact with the spark plug.

Stirlingkit Note: Good spark plug contact matters most with the MCU's coil-on-plug ignition. See how the coils perform in Jamie's coil test.