Experienced gardeners share their insights in answering this question :
Page 7 Item 22. Below the “H” & “L” needle valves (items 20 & 21).
If the chain chatters it is to fast or the clutch needs repair. I think CCW is faster, make small adjustments, blip the throttle let it settle.
On the engine cover there are often 3 holes for needle valve adjustment. Idle is usualy marked “T”.
If you have an Owner’s Manual the location is usually displayed somewhere within. I could not find an on line OM. HTH

How to Identify and Fix Common Gardening Problems ?

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Turn the idle screw — I — clockwise until the chain starts to spin, then turn it counterclockwise slightly. Adjust the screw to find the highest setting possible without making the chain spin. Check the setting by holding a digital tachometer over the spark plug. It should read between 2,700 and 2,900 rpm.
The two most common reasons a chainsaw won`t idle are a blocked air filter and an idle screw out of adjustment. Other possible causes include: Dirty Air Filter. Idle Screw out of Adjustment.
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In 1999 McCulloch sold its European division to Husqvarna AB. Nine years later, Husqvarna also acquired the rights to the McCulloch brand on the North American market. Since then, McCulloch is a brand within the Husqvarna Group.

Set idle speed adjusting screw, clockwise to increase rpm, counter-clockwise to decrease rpm. Idle rpm range should be 950 to 1050 rpms. Adjust idle mixture by turning idle mixture screw slowly clockwise until the engine runs poorly.
There are many factors that can stop your chainsaw from running, including a bad spark plug or dirty air filter. There are simple problems: a broken fuel line, bad fuel, wrongly calibrated high-low adjustment screw. Also, more complex issues like a damaged carburettor or an engine compression problem.
The most probable – and easiest to fix – cause of chain rotation while the chainsaw engine idles is a poorly adjusted idle setting on the carburetor. The result is that too much fuel is delivered to the combustion chamber when the throttle is released, and the engine doesn`t really slow.
This switch breaks the flow of current through the primary coil and causes a voltage spike (of perhaps 200 volts). The secondary coil, having 100 times more turns than the primary coil, amplifies this voltage to approximately 20,000 volts, and this voltage feeds to the spark plug.
With no dangerous connections or wires, McCulloch chainsaws are easy to use and very durable. The biggest advantage is that it`s cordless, and as long as you have a full fuel tank, you can take full reign of the garden. We can help you decide with these quick questions.
The McCulloch CS 35 16 is powered by a 1.4 kW (1.9 HP) two-stroke engine 35 cc.
Bring the car to a stop or keep it in park.

If your car is in motion, apply gently increasing pressure to the brake pedal to slow the car until it comes to a stop. If the car is in park, you won`t need to do anything special. As the car runs while stationary, the engine will idle.

Idle speed is controlled by using an electronically controlled throttle bypass valve, as seen in Fig. 6.6, which allows air to flow around the throttle plate and produces the same effect as if the throttle had been slightly opened such that sufficient M . a flows to maintain engine operation.
The Idle air control valve or the IAC valve controls your engine`s idle speed and is controlled by the engine`s onboard engine computer system. The IAC valve controls the amount of air circulating around the closed throttle plate.
On most carburetors, turning the mixture screw in (clockwise) leans the mixture, while counterclockwise (out) enriches the mixture. Initially, if the engine stumbles or the vacuum drops when turning the mixture screw in, turn both screws out about a -turn and evaluate the results.
There are many factors that can stop your chainsaw from running, including a bad spark plug or dirty air filter. There are simple problems: a broken fuel line, bad fuel, wrongly calibrated high-low adjustment screw. Also, more complex issues like a damaged carburettor or an engine compression problem.

Discover Relevant Questions and Answers for Your Specific Issue

the most relevant questions and answers related to your specific issue

McCullough chainsaw won't start – McCulloch Quality Mcc1435a 14" Gas 35cc 2 Cycle Chainsaw Full Warranty
ANSWER : If it’s a old saw..The seal goes out on the crank next to the clutch,it’s called a grease seal, it loses the suction needed to pull fuel in to the engine, can be a tricky one to replace, but will spark a old saw back to life. You may want to replace both crankshaft seals ..First try a few drops of gas down the carb, if it pops off you know it’s a fuel issue

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I have a new Husqvarna chain saw and when it is turn on its side it dies whats wrong.
ANSWER : Its hard to say what is causeing this, there will always be a slight difference in rpm as it moves from side to side, the fuel hose should move in the tank and follow the fuel, if the machine is idling to low it may stop as you turn it, make sure the fuel hose is not trapped in the tank.

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My chain rotates on idle when tension is ok. How do I adjust clutch drum to stop this happening ?
ANSWER : The clutch drum is probably ok, just turn the idle adjustment screw CCW to reduce idle speed (not the jet screws). If you turn it too far, the engine will stall.

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I can;t get any oil to feed on the bar of my McCulloch MCC4516FK chainsaw
ANSWER : No gasket you need a little bigger gas line to seel the hole.

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Powermac 310 no spark
ANSWER : How do I test the ignition module out off the chainsaw? Or how do I know an ingnition module is working properly prior to instalation?

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No spark how to disensemble
ANSWER : Try disconnecting kill switch wire off kill switch.or coil,unscrew screws out of LHS cover, Plus take top cover off,should be able to access wire.if still no spark,coil needs replacing

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I have a mac 3516 with a weak spark.I am looking for the gap spec
for the pickup coil.
ANSWER : The gap should be 0.5mm

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My titan 70 also has a oil leak when it is left sitting what would be my problem
ANSWER : The bar oiler can leak oil. Make sure the cap is on good.

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