QuestionQUESTION: I have a Craftsman Electrical Saw Model 316.341070, 120v 69hz, 13.5 A. It stopped working last year when it was being heavily used. Repairing through sears cost more than the buying a new one. It may be a simple thing, like replacing a fuse, if such thing is used inside. I do not have a manual. If you can give me suggestions as to possible cause of problems and how to approach them, I will give a try.
ANSWER: Hello Makoto:
There is an Internal Circuit Breaker. If the Saw has Been Unplugged for 10 Minutes and the Motor Fails to Run, then Check the Trigger. The Trigger will Heat Up and Melt on the Inside and the Contacts Can Not Connect. Go to this Site Addy, http://www3.sears.com/ and Enter the Model Numbers in the Search Box at the Upper Left and Click Go. Then Visually Verify the Equipment and Click Continue. Now you can Select Either View Diagram or View Parts List. Hope this Helps. I am Here if You Require More Assistance. Let Me Know What Happens, Please. Thanks.
Good Luck
Respectfully
John
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QUESTION: I checked Sears diagram and opened the saw. The trigger is red plastic and did not seem to be damaged and operates to push the switch ok. I checked the electric current using a tester, and found it did not reach beyond the switch (#17 in their diagram). So, I short circuited the wire bypassing the switch. Then, I found the electric current still was blocked at the second switch (#51? in their diagram- I am not sure because the diagram image is so poor), so again I bypassed it to connect the wire. Now the power reached the motor and it started running, but it generated smoke and stopped after few seconds of operation. After a short period of cooling, it started again, but again stopped. Is the motor damaged and to be replaced? The switches should be also replaced, I suppose? What should I do?
ANSWER: Hello Again Makoto:
The Windings are Shorted and are Drawing to Much Current, Hence the Getting Hot, Smoking and Quiting. The Short Most likely Burned the Contacts in the Switches. Replace the Saw. Hope this Helps. I am here if you Require more Assistance. Let me know what Happens, Please. Thanks.
Good Luck
Respectfully
John
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QUESTION: Thanks for your reply. What is windings? Did what I just did break the saw, or was that broken already? Are you recommending buying a new saw rather than replacing 2 switches? Why?
AnswerHello Again Makoto:
The Windings are in the Field Coils and the Armature of the Motor. Usually the Cost of New Field Plates or An Armature are the Close to or the Same as Purchasing a New Saw would be. These are Coils of Wire Wound Together to Form the Outer Magnetic Field when the Current is Connected to the Field Coils. From your Description, the Getting Hot, Smoking and Quitting; I Know from Experience that the Windings in Either the Field Coils or the Armature have Shorted. You Didn't Cause the Bad Motor. The Windings Short is the Cause for the Switches Burning Out. Usually, when you Jump the Switches, the Motor (if good) will Run as Designed, just No On and Off Control other than Disconnecting the Power Source. Usually the Windings Short Due to Excessive Heat. This can be Caused by Several Reasons. 1- A Drop Cord that is too Small and Does Not Carry the Required Electrical Current for the Engine to Run Properly. 2- Operating the Saw Under a Strain for an Extended Period of Time, without Allowing a Cool Off Period Between Cuts. 3- Brushes Worn Out. These are the Most Common Causes for the Windings in an Electrical Motor to Short. Yes I Recommend Purchasing a New Saw. Hope this Helps. I am here if you Require more Assistance. Let me know what Happens, Please. Thanks.
Good Luck
Respectfully
John
