Homelite Super 2 No Idle

artemjemmy

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I have a homelite super 2 (the one with a 2 piece plastic clamshell), that will run great at open throttle, but when you try to let it idle, it gradually decreases in speed and dies after about 10-15 seconds. Idle mixture and idle speed adjustment make basically no difference, unless you have the idle speed set so high that the clutch engages. When I go to restart it, I need to turn the choke on all the way, which makes me think the metering cavity ran out of gas? I already replaced the needle and the fuel pump diaphragm and metering diaphragm, and adjusted the metering arm with the proper walbro tool, with absolutely no change in the symptoms.
 

hlw49

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I have a homelite super 2 (the one with a 2 piece plastic clamshell), that will run great at open throttle, but when you try to let it idle, it gradually decreases in speed and dies after about 10-15 seconds. Idle mixture and idle speed adjustment make basically no difference, unless you have the idle speed set so high that the clutch engages. When I go to restart it, I need to turn the choke on all the way, which makes me think the metering cavity ran out of gas? I already replaced the needle and the fuel pump diaphragm and metering diaphragm, and adjusted the metering arm with the proper walbro tool, with absolutely no change in the symptoms.
If I remember correctly that saw has an HDC carb. If it does it should have a check valve in the high speed circuit. If it is bad it will cause long come down and cause the engine to die at idle. Check the high speed check valve. Take a piece of fuel line and stick it over the check valve and see it closes when you draw a vacuum on it.
 

StarTech

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Personally I haven't seen a Homelite Super 2 with a two piece clam-shell. Now late models of Homelite do use the clam-shell design. I just finish up an UT-10829 Homelite that was the clam-shell design. What is the UT number so I can look-up the IPL?

Did you bother to clean the carburetor using an ultrasonic cleaner with soap and water or did you use standard carburetor cleaner? Standard carburetor cleaner will damage the carburetor internal rubber check valves. But your problem hints at crankcase vacuum leak. Crankshaft seals are main the culprit of vacuum leaks but other gaskets can also cause a vacuum leakage. You need to do a pressure/vac test to verify this.

Another cause can be lost of compression. These saws have normal compression in the range of 120-150 psi with 100 psi being the bare minimum compression that they will idle at. If it turns to be a compression problem then the saw is just a boat anchor due parts costs.
 

artemjemmy

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Personally I haven't seen a Homelite Super 2 with a two piece clam-shell. Now late models of Homelite do use the clam-shell design. I just finish up an UT-10829 Homelite that was the clam-shell design. What is the UT number so I can look-up the IPL?

Did you bother to clean the carburetor using an ultrasonic cleaner with soap and water or did you use standard carburetor cleaner? Standard carburetor cleaner will damage the carburetor internal rubber check valves. But your problem hints at crankcase vacuum leak. Crankshaft seals are main the culprit of vacuum leaks but other gaskets can also cause a vacuum leakage. You need to do a pressure/vac test to verify this.

Another cause can be lost of compression. These saws have normal compression in the range of 120-150 psi with 100 psi being the bare minimum compression that they will idle at. If it turns to be a compression problem then the saw is just a boat anchor due parts costs.
Turned out it was the gasket for the reed valve to the block leaking. I sprayed brake cleaner around there and it basically fixed itself and started idling right, so I took the gasket off cleaned the surfaces off as best I could and I used high temp rtv to make a gasket. Runs good now
 

upupandaway

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Turned out it was the gasket for the reed valve to the block leaking. I sprayed brake cleaner around there and it basically fixed itself and started idling right, so I took the gasket off cleaned the surfaces off as best I could and I used high temp rtv to make a gasket. Runs good now
I have a David Bradley 360 chainsaw. I had to rebuild the reed valve on mine(it was stuck open). Spring steel from a feeler gauge and Epoxy did the trick.
 

artemjemmy

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I have a David Bradley 360 chainsaw. I had to rebuild the reed valve on mine(it was stuck open). Spring steel from a feeler gauge and Epoxy did the trick.
how far stuck open? The super two's reed valve had a resting position of about 30 thousandths open when I took it off. I read that any gap at all when in a resting position was bad, but it runs fine as it is.
 

upupandaway

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how far stuck open? The super two's reed valve had a resting position of about 30 thousandths open when I took it off. I read that any gap at all when in a resting position was bad, but it runs fine as it is.
It was open probably 1/8". There was plenty of blowback that a puddle of gas would build up in the carb. Runs like a top now.
 
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