QuestionEric -
I have a nice old Poulan 71A chain saw, 1961, and it has always been such a great saw - simple, powerful, loud, and heavy. The ignition system is very simple - a cam actuated contact point, a coil, a condensor, the magneto (flywheel), and the spark plug/wire. My problem is that I have no spark. The other problem is that the parts are very hard to find. I bought the only condensor I could find several months ago, and have about 1 or 2 hours run time since. My question is this : what EXACTLY is the function of the condensor, and if I suspect it can I test it? If I can't test it to confirm its functioning, can I replace it with a similar-but-not-exactly-the-same condensor? How are they rated/spec'ed?
Simlar question for the coil - how do I test it? I'd like to confirm it's integrity also. With my meter, what should I see and where?
ANy help will be very appreciated. Hurricane Frances looms and I need my saw!
Kindly -
Scott Carter
AnswerThe condenser acts a storage for AC voltage generated by the magnets and coil. You can check it with and analog OHM meter. Touch one clip lead to the condenser end and the other to the condenser case. The meter should quickly short, 0 ohms and then slowly fall to infinity. A condenser tester is best but they are expensive and very few shops still have them.
You can replace the condenser with another. Condensers are rated in farads, usually micro-farads, and voltage. Pretty much any automotive type condenser will work.
As for the coil, there should be about 4K ohms between the plug wire and coil wire. As long are there is some resistance you should be alright...you do not want 0 ohms, this indicates the coil is shorted.
I actually have a coil tester that tests coils. It works very well but is very expensive...over a $1000.00.
Have you tried one of the electronic ignition modules? I have installed severel on old equipment like yours and they work well.
Let me know.
Eric
