# points delete



## lanche (Jun 8, 2005)

Hi I have an old John deere backpack blower that quit running so I've checked spark and I get nothing by grounding the plug but I get a weak spark when using a small bolt. I've checked and cleaned all connections and wiring. I had the coil checked and it was good. This unit has a points delete box thing that I'm thinking is bad. Can these things be checked or where can I find a new one... thanks


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## wa5ngp (Aug 14, 2010)

After years of tinkering with these kinds of motors I have never found a coil that went bad. The reason the spark looks weak when tested is that when we spin the motor to get the spark we don't spin it fast enough. So my test is to hold the wire in my hand, spin it around, if I feel something its probably ok. So far this has served me well as a shadetree test.

About 30 yrs ago on my first weed eater I was convinced the coil was bad. I went to the local shop. The man said "I'll sell you one, but its not the problem and I can't give you a refund so before buying please keep that in mind." I thanked him and went home to clean up the carbs and get it going again. This was before primer bulbs. Lots of pullin' required to get fuel in there.

don


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## lanche (Jun 8, 2005)

I had the coil tested and it was fine the part I'm looking at is the points delete item that was installed years ago. I'm not sure what it was is called or how to check. When I'm checking for spark I do while looking and feeling for spark. Sometimes you might get a jolt but it's not to bad.


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## 30yearTech (Sep 14, 2006)

It's a Solid State conversion kit for old points and condenser systems. For a short while they were factory installed before they started making the integrated modules with the coil. 

They are available through after market suppliers such as Stens, Oregon and Rotary. Here are a couple that are available from Rotary:

http://www.m-and-d.com/RO-9334.html

http://www.m-and-d.com/RO-8786.html

Coils do fail, I have seen many over the years, but it's much more common for the trigger to fail then the coil. Typically when a coil fails it's preceded by loosing spark when hot and then working again when cool, after awhile, they fail completely.

You cannot tell a sparks intensity by looking at it, as the color of the spark does not reveal it's intensity. A gap type spark tester is the best, and sometimes you just have to listen for the "POP" the spark makes when jumping the gap. Solid State ignitions generally do require higher minimum RPM to produce an ignition spark, but cranking speed is sufficient to produce a spark.


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## lanche (Jun 8, 2005)

Running bad when it got hot was his original complaint before it died completely. I had the coil tested. Do you think it could test good cold but really be bad and if I get a new coil will I still need the conversion kit or will that be in the new coil?....thank you


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## wa5ngp (Aug 14, 2010)

That's a good question since I would think that heating causes expansion that causes a break in a connection somewhere internally. You could heat it up (carefully) in an oven and then check it. I have not had much success with using heat guns for this kind of job, I usually end up destroying everything.

good luck on this, proceed patiently. You'll figure it out.


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## 30yearTech (Sep 14, 2006)

lanche said:


> Running bad when it got hot was his original complaint before it died completely. I had the coil tested. Do you think it could test good cold but really be bad and if I get a new coil will I still need the conversion kit or will that be in the new coil?....thank you


It is possible that the coil could still be an issue if it has a problem when it's hot, however if your not getting any spark now and it tested good, then you likely have a problem with the conversion box.

A new coil will still need the conversion box, you would have to check and see if there was ever a complete solid state replacement unit made to fit the blower. What is the model number of the blower?


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## lanche (Jun 8, 2005)

It's John deere model TY9502..40cc. I can't seem to find any engine numbers. I'm being told that maybe Echo made these but not sure...thanks


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## 30yearTech (Sep 14, 2006)

That is an Echo unit, looks like an old PB-400. They don't show the coils to be available any longer. They were very popular blowers, especially for commercial use, so there is likely a huge graveyard of used parts somewhere for them. The solid state models utilized a 2 piece ignition setup, with a module that had the primary windings and trigger and then a second step up transformer that had the spark plug lead and was mounted externally and away from the flywheel.


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## lanche (Jun 8, 2005)

Well I do have another blower for parts and it's a Toro but it has an external unit with the plug wire so the other piece might be on the back side of the motor. Maybe I could use the whole ignition system. I will check this weekend...thanks


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## lanche (Jun 8, 2005)

Ok since I last posted I replaced the ignition system which now gives me good spark but wouldn't start. I cleaned the carb and replaced gaskets put in fresh fuel and new fuel lines. I still can't get it to start all it does is pops out the carb and blows fire out the exhaust. Does anybody have any idea what I'm looking for?.....Thanks much.


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