Odd problem, never run across this...

[naturelover]

Thought I had the Shindaiwa 500 sorted out, as I cut with it last weekend with no problems.

Was having problems with it not getting spark, but after some tinkering thought I had it fixed.

I regapped the new coil a couple times already, new plug, new switch wires, and even another new plug. Not sure what or how I fixed it, but finally got spark.

Well, went to start it today, and no spark. Not wanting to tear it apart again, tried pulling on it some more to see if something would happend.

But no luck. Went to dry the plug with the propane torch. Well, that led me to wonder what would happen if I took the whole saw to the heated basement and let it sit for a while.

I'll be dang if it didn't start on the first pull.... :bang:

Shut it off after cutting up and noodling some wood, started right back up. Let it sit for a few hours, pulled the plug, and had a fat, blue spark.

Coinkidink? Surely has me stumped...

I guess I'll see if I can let it get cold again and see what happens in the morning, or start cleaning out some space in the fridge...

 

[timmcat]

When you've played with the coil have you cleaned the mounts down to bare metal with sandpaper? If there is any oxidation on the posts wierd stuff happens on those old ignitions.

 

[eiklj]

I've just finished getting my Shindi 488 up and running. I assume it must be similar to the 500.
Anyway, this thing has about 5 ft of wire running to & from the coil and module and on/off switch. I was thinking it could possibly be those goofy bullet connectors maybe not making good contact or have moisture trapped in them?
Or maybe a bad plug wire? Maybe the plug wire not making good contact with the coil? I'm just thinking out loud here. I hate electrical problems as they aren't consistent.
Don't know if this helps or not.

je

 

[timmcat]

I've just finished getting my Shindi 488 up and running. I assume it must be similar to the 500.
Anyway, this thing has about 5 ft of wire running to & from the coil and module and on/off switch. I was thinking it could possibly be those goofy bullet connectors maybe not making good contact or have moisture trapped in them?
Or maybe a bad plug wire? Maybe the plug wire not making good contact with the coil? I'm just thinking out loud here. I hate electrical problems as they aren't consistent.
Don't know if this helps or not.

je

488 and 500 are completely different animals. 488 has vertical cylinder and two piece ignition system, 500 has horizontal cylinder and two or three piece ign depending on vintage. Best way to diagnose multi part ignitions is by using parts from a known good running saw, there are no good (reliable) tests for the ignitor or secondary coils. I have heard of guys using the ignitor from a kawasaki fb460 mower engine in place of the Shindaiwa part, but haven't myself so I dont recommend it.

500 ign system
OEM Parts

488 ign system
OEM Parts

 

[a. palmer jr.]

Since your spark is inconsistent I would guess the first thing is to make sure you have clean, tight connections. Any corrosion should be removed. It doesn't sound like it should need any parts, just routine maintenance.

 

[rmh3481]

Usually ignitions fail when they warm up. What kind of spark plug are you trying? Shindaiwa 488 calls for CJ6Y Champion or BPM7A NGK. The older ignitions wont want to fire a plug with a resistor in it, look for an 'R' in the name on the plug like Rcj6y. Ditch the R plug if that is what your trying.

Two part ignition, exciter coil air gap is .012 to .014 inch.

Do you have a volt meter? Test the stop switch for internal grounding by checking for any resistance in the run position. If there is any resistance, you need a new switch. Its best to unplug the switch while your doing these tests anyhow, just dont overlook it.

Ive got the Shindaiwa books and will try to get you the ignition test data if you have a volt meter. These are ohm load tests for the coils. Send me an email address via private message if you want a copy.

 

[naturelover]

Thanks for all the suggestions!!

Well, I let it sit overnight, was in the 30s this a.m., and yup, you guessed it.

Fired right up.

Tried it again later today, same result, runs and idles great.

Don't guess its temperature related, but as eiklj suggested, maybe its moisture related? Might try spraying it down or something and see what happens.

The spark plug is a BMP6A, the new one before that was a CJ8, and the coil gap was set with a business card, which I later measured and was .010.

When it was dead before, I disconnected the switch entirely, but still a no go.

I checked the connector from the coil to that little box, but will go back and put some dielectric grease on it for good measure. The wire from it does seem quite stiff, but I've messed with it before and it didn't seem to change anything.

What is that little box anyway exactly? I've tried to look it up by the parts diagrams, but they all point to the wire, which has the same part number....

PM sent rmh3481, much appreciated.

 

[fearofpavement]

Do you have a volt meter? Test the stop switch for internal grounding by checking for any resistance in the run position. If there is any resistance, you need a new switch. Its best to unplug the switch while your doing these tests anyhow, just dont overlook it.

There should be infinite resistance if the switch is in the "open" position. ie, a LOT of resistance.

 

[a. palmer jr.]

Do you have a volt meter? Test the stop switch for internal grounding by checking for any resistance in the run position. If there is any resistance, you need a new switch. Its best to unplug the switch while your doing these tests anyhow, just dont overlook it.

There should be infinite resistance if the switch is in the "open" position. ie, a LOT of resistance.

That's true in most cases. In other cases, however, they use the connection at the stop switch to complete a circuit in the primary to make it run. I found that out by working on my old Lawn Boy mower.