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View Full Version : Echo-370 Chain Saw Full Throttle Problem


jud149
02-02-2012, 02:48 PM
This saw has only about a couple of hours on it but is several years old. I used it about a year ago and it ran fine. I ran the gas out of it before storing it. Today it will not run a full speed, only 3/4 and then will cut out periodically. However, it does idle fine. Now I just noticed that if I run it at about 1/4 choke, it will run at full speed.

The filters are obviously clean and I put a new plug in it as the old one was black, and removed the spark arrester which was clean. I tried to adjust the carb but to no avail. You can only turn the screws a half turn or so. Any ideas or is this just another carb I will have to rebuild because of ethenol? I have recently converted to non-ethenol fuel.

dutch1
02-02-2012, 03:18 PM
Remove the limiter cap and open the high speed needle a bit at a time--see if that might help.

jud149
02-02-2012, 05:33 PM
Remove the limiter cap and open the high speed needle a bit at a time--see if that might help.

Thanks! Would you happen to know how to get the limiters off? I have the top and side off the saw but still can't see how to get to them. They are flush with a metal base with limited access.

piston slapper
02-02-2012, 08:19 PM
Walbro makes a tool that threads into the caps and threads them off.
You may be able to thread a small screw into the caps and pull them out.
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dutch1
02-03-2012, 12:22 AM
The proper way to remove the external limiters is with the Walbro tool as Slapper suggested. I've also heard of guys running a sheetmetal screw into them to push them off but have never tried that method. I've always use a duckbill plier to grasp the outer part of the limiter and pull straight out--along the same axis of the adjustment screws. Twisting or bending may result of bent needles or possibly breaking the needle off in the carb. I've even cut them off with a pair of miniature side cutters.

jud149
02-03-2012, 08:58 AM
The proper way to remove the external limiters is with the Walbro tool as Slapper suggested. I've also heard of guys running a sheetmetal screw into them to push them off but have never tried that method. I've always use a duckbill plier to grasp the outer part of the limiter and pull straight out--along the same axis of the adjustment screws. Twisting or bending may result of bent needles or possibly breaking the needle off in the carb. I've even cut them off with a pair of miniature side cutters.

There's no way to remove the limiters with pliers as they are flush with a metal extension on the carb. I probably can get them off with a screw as suggested but once the carb is adjusted, I believe they must be replaced since the adj. screws have no spring to hold them in place. What a joke. I knew there was a reason I keep my old Echo SRM 1501 weed whacker despite having some minor problems with it. Thanks again for your help, guys.

jud149
02-03-2012, 09:14 AM
I should add that the old ones will probably be destroyed and I understand new ones are not easy to come by. Does anyone know where to buy the tool?

piston slapper
02-03-2012, 10:30 AM
Jud....the caps aren't gonna make it run any better.
You can pry out the aluminum face cover that is shielding the screws, with a flat screwdriver.
Once you get the caps off the screws, they'll just look like screws.
A whole lot more user friendly.
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dutch1
02-03-2012, 02:12 PM
It appears that all CS370 serial number ranges use either the WT829 or WT794.
Unless I'm out of the loop somewhere, the limiters are external to the carb body, not recessed. The limiters are retained by a collar on the adjustment screws. I've always been able to pull straight off with pliers.

http://echoinc.arinet.com/scripts/EmpartISAPI.dll?MF&app=ECHO&session=1f94e354-1a23-42a1-a402-5133329c659b&cat=2&TF=epcFrame&assem=8742&serialGroup=0&modelAssemID=&highlightNode=No&selAssem=7389&mdDescrip=CS-370%20%20S%2FN%3A%20C08011001001%20-%20C08011999999

piston slapper
02-03-2012, 02:38 PM
You're probably right. Dutch.
My research dept has been out to lunch for some time.
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dutch1
02-03-2012, 02:57 PM
Well, Slapper, it appears my research dept is out to lunch as well.
The link didn't pan out--"undefined", when I clicked on it. At any rate, the info is on Echo's website.

jud149
02-03-2012, 03:00 PM
It appears that all CS370 serial number ranges use either the WT829 or WT794.
Unless I'm out of the loop somewhere, the limiters are external to the carb body, not recessed. The limiters are retained by a collar on the adjustment screws. I've always been able to pull straight off with pliers.

http://echoinc.arinet.com/scripts/EmpartISAPI.dll?MF&app=ECHO&session=1f94e354-1a23-42a1-a402-5133329c659b&cat=2&TF=epcFrame&assem=8742&serialGroup=0&modelAssemID=&highlightNode=No&selAssem=7389&mdDescrip=CS-370%20%20S%2FN%3A%20C08011001001%20-%20C08011999999

My saw has the WT829. I assure you they are recessed. My concern, as mentioned, is after their removal, the needles will have nothing to hold them in place as these adjusters have no springs per the WT829 diagram. Thanks...

Landrus2
02-03-2012, 03:04 PM
we over look this :waving:

jud149
02-03-2012, 04:31 PM
we over look this :waving:

Thanks. The saw only has a couple of hours on it and I did check the spark screen and it's clean. Anything else to check??

piston slapper
02-03-2012, 08:41 PM
Jud...I looked around the shop and could not find a single carb with springs on the adjustment screws.
Over 100 Stihl, redmax,echo, commercial units. Most have been adjusted at some point and the caps ain't around.
I believe the screws have an interference thread because once they are adjusted, they stay adjusted.
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jud149
02-03-2012, 08:49 PM
Jud...I looked around the shop and could not find a single carb with springs on the adjustment screws.
Over 100 Stihl, redmax,echo, commercial units. Most have been adjusted at some point and the caps ain't around.
I believe the screws have an interference thread because once they are adjusted, they stay adjusted.
Posted via Mobile Device

Many thanks. I guess I'll get to work and see if I can get the limiters off. I just don't get how they get away with making crap like this.