Echo CS-590 Timber Wolf Cold Start Procedure: Step-by-Step
Getting a cold engine fired up on the Echo CS-590 Timber Wolf can sometimes feel like a battle of wills, especially after it has sat for weeks or during chilly mornings. This 59.8cc pro-grade saw runs a Walbro carburetor and a fixed low-speed jet, meaning the starting ritual is a specific sequence that respects its design. Here’s the reliable, gravity-tested method that gets the piston past compression without flooding the cylinder or wearing out your shoulder.
Why Won’t My Echo CS-590 Timber Wolf Start Cold?
If you’re pulling the starter rope and getting nothing but a warm arm, the root cause is almost always a lack of fuel vapor in the cylinder or an overly rich mixture from a flooded state. The CS-590’s carburetor design—specifically its lack of an adjustable low-speed mixture screw—means you cannot lean out the idle circuit to compensate for a choked engine. Three common cold-start failures are: the decompression valve not engaging (preventing enough pull speed), the choke plate not closing fully due to a dirty linkage, or the purge bulb not being filled to the top with liquid fuel.
Start by inspecting the spark arrestor screen. Even a partially clogged screen can restrict exhaust flow and make a cold engine impossible to start. Remove the three screws on the muffler cover and check the mesh for carbon buildup. A clean exhaust path is as critical as a good spark.
What Is the Correct Starting Sequence for a Cold CS-590?
The official procedure in the owner’s manual works, but experienced operators add two critical details. First, push the decompression valve until you hear a distinct click—it’s a spring-loaded button on the left side of the cylinder housing. Second, set the master control lever (the choke/fast idle combo) to the cold start position, which is the uppermost detent. Here is the exact five-step sequence:
- Step 1: Prime the purge bulb firmly 5-6 times until you see liquid fuel, not just bubbles, flowing through the clear return line. This fills the carburetor bowl and displaces air in the metering chamber.
- Step 2: Pull the starter rope slowly until you feel the first compression stroke, then give a single, sharp, full-length pull. On the first pull, the engine will typically cough or fire once but not run.
- Step 3: Move the master control lever down one position to the “Run” setting (this removes the choke and engages the fast idle cam). Do NOT go to the idle position yet.
- Step 4: Pull the starter rope again with the same sharp motion. The engine should start within 2-3 pulls, then immediately rev at fast idle for 10-15 seconds.
- Step 5: Once the saw runs steadily at fast idle, squeeze the throttle trigger once to disengage the fast idle cam and let it settle into normal idle.
If the engine does not fire after six pulls with the choke closed, you have flooded it. Wait 60 seconds with the master control lever in the run position, open the throttle fully (without using the choke), and pull the rope 4-5 times to clear excess fuel from the combustion chamber.
How Does Decompression Valve Use Affect Starting on the Timber Wolf?
The decompression valve on the Echo CS-590 is not a gimmick—it reduces the cylinder compression by about 40% during the starting stroke by venting compressed air through a port. If you skip pressing it, the engine will still start, but you’ll need significantly more arm speed to overcome the 165 psi of compression from the 46mm piston. For cold starts, always press the valve before attempting the first pull. The valve automatically reseals once the engine fires after the second pull series.
A common mistake is pressing the valve after the first pull sequence when the engine is already partially flooded. That defeats the purpose because the valve only vents gas on the compression stroke; it cannot remove liquid fuel from the cylinder. Use the decompression valve only before the very first pull of the day.
Should I Use Starting Fluid or Ether on an Echo CS-590?
The short answer is no—and you risk serious damage. The Echo CS-590 uses a Walbro WYL carburetor with a fixed high-speed mixture set at 1.5 turns from seated and a non-adjustable low-speed circuit. Starting fluid (ether) has an octane rating far lower than the 89 octane minimum the saw requires and can cause detonation, scoring the piston skirt. More critically, ether washes away the thin film of oil on the cylinder walls, leading to ring wear on the first few revolutions. If your saw won’t start cold using the choked prime method and a clean spark arrestor, inspect the fuel line and impulse hose for cracks. A 20:1 premix ratio is far too rich and will also cause hard starting; use 50:1 with a high-quality synthetic oil like Echo Red Armor.
| Issue | Severity |
|---|---|
| Compression valve not pressed before start | Usually not urgent—will still start with strong arm, but unnecessary wear on starter pulley |
| Fuel sat in carb for 6+ months with ethanol | Needs attention soon—likely clogged low-speed jet in the Walbro carb |
| Choke plate not closing completely | Needs attention soon—will prevent cold start, requires cleaning linkage |
| Spark arrestor screen clogged with carbon | Needs attention soon—restricts exhaust post-fire, may cause flooding on restart |
| Damper spring on recoil assembly broken | Needs attention soon—recoil rope won’t retract, but saw can still start with manual pull |
| Fuel filter in tank sucking air instead of fuel | Needs attention soon—hard starting every time, not just cold |
What About Storing the CS-590 Between Uses to Improve Cold Starts?
Proper storage directly correlates to how easily the saw fires up on a cold morning. If you leave the saw with fuel in the carb for more than two weeks, the volatile components of the gasoline evaporate, leaving a varnish-like residue that plugs the tiny idle bypass ports. Before storing, run the carburetor dry by running the saw at idle until it stops on its own. Then, remove the spark plug and squirt about 1cc of synthetic oil into the cylinder, pull the rope 2-3 times to coat the rings, and reinstall the plug. This keeps the compression high for the next cold start. Also, drain the fuel tank if it is not going to be used for 30 days—Echo’s fuel cap has a breather that can let moisture in if the saw is stored in a damp shed.
If you store the saw for the winter and plan to use it in spring, consider running a fuel stabilizer (Sta-Bil or equivalent) in the last tank of the season. The CS-590’s plastic fuel tank is ethanol-tolerant, but the carb diaphragm is not. When you go to start the saw after three months of storage, follow the same five-step procedure, but expect it to need an extra pull or two while the dried-out diaphragm reseals itself.
How Do Ambient Temperature and Altitude Affect the Cold Start Procedure?
Temperature and altitude directly influence the fuel-air mixture the engine sees during a cold start. For example, at 20°F (-7°C), gasoline does not vaporize as readily, so you may need to hold the choke on for four to five pulls instead of one or two before switching to the run position. At high elevation (above 5,000 feet), the thinner air reduces the engine’s ability to draw air through the carb, which may require you to skip the choke altogether on the second pull sequence. The CS-590’s fixed low-speed jet is calibrated for sea-level operation, so at altitude, the mixture becomes richer. This can flood the engine quickly if you over-prime the bulb. A good rule is: at elevations above 7,000 feet, try starting with four prime strokes instead of six, and shift to the run position after the first pull that produces a pop.
Conversely, in hot weather (90°F+), the fuel in the line can vaporize, creating an air lock. In those conditions, you might need to prime the bulb until you see fuel streaming out of the carb overflow line (the small hose on the bottom of the carb). This clears the vapor lock and ensures liquid fuel reaches the nozzle.
What Owners Say About Starting the Echo CS-590 Timber Wolf
Regular users of the CS-590 in the field have shared practical observations. One firewood cutter from Oregon noted that after switching from a Stihl MS 261 to the Echo, he initially flooded the saw three times in a row because he was used to a different choke mechanism. He found success by reducing his prime strokes to five and committing to the two-pull sequence without hesitation. A landscaping professional in New York mentioned that his CS-590 started first pull every time after he replaced the spark plug with an NGK BPMR7A and cleaned the air filter weekly. Another owner observed that the saw starts noticeably easier when using non-ethanol fuel (91 octane), because ethanol attracts moisture that oxidizes inside the carb passageways, causing the saw to require a full seven pulls when cold. Several owners also report that leaving the saw in the sun for 10 minutes before starting in winter reduces the number of pulls needed by half, as the fuel warms slightly and vaporizes more readily.
Frequently Asked Questions
How many pulls should it take to cold start an Echo CS-590?
Typically, a properly maintained CS-590 should start within 2-3 pulls after the initial choke step. The first pull with choke should produce a cough, then shifting to run results in a start within 2-3 pulls. If it takes more than 6 pulls total, check the fuel and spark.
Why does my Echo CS-590 need a choke restart after sitting for 10 minutes?
This is a symptom of vapor lock in the fuel line or a partially clogged idle jet. The engine is hot enough to vaporize fuel in the carb bowl but not hot enough to vaporize the return line fuel. Try priming the bulb once and pulling with the choke on the run position before trying full choke.
Can I damage the starter rope by pulling hard on a cold engine?
Yes, excessive force can strip the teeth on the plastic recoil pulley. Use a smooth, steady pull rather than jerking violently. If the decompression valve is pressed, a moderate pull is sufficient to spin the engine past compression.
What fuel mix works best for cold starts on the Echo CS-590?
Use a 50:1 ratio with synthetic oil (Echo Red Armor recommended). A leaner mix (40:1) creates more carbon deposits that clog the spark arrestor and foul the plug, making cold starts harder. Stick to the manufacturer’s spec.
Does a new Echo CS-590 require a special break-in procedure for easier starting?
Echo recommends running the first 3-4 tanks of fuel at 50:1 without heavy full-throttle loads. This allows the piston rings to seat properly. Do not attempt to tune the carburetor during break-in; the fixed settings are designed to be rich during this period, which can make cold starts slightly more difficult until the engine is broken in.
How often should I replace the spark plug for reliable cold starts?
Replace it every 100 hours of operation or once a year, whichever comes first. Use an NGK BPMR7A or equivalent. A weak spark may still fire a warm engine but fail on cold starts due to the dense fuel mixture and lower battery voltage from the recoil start.
For a more detailed comparison of how the CS-590 stacks up against the Stihl MS 261 C-M, see our Echo CS-590 Timber Wolf vs Stihl MS 261 C-M: Which Is Best for Firewood? guide. If you’re adjusting the oiler, refer to How to Adjust Oil Flow on Echo CS-590 Timber Wolf. For broader buying advice, check out our Echo CS-590 Timber Wolf Buying Guide: Is It Right for You?