Testing an igniter?

[marcg]

My '98 Sprint Exec won't start and I suspect the igniter (see below for why). Is there some way that I can test the igniter with standard tools? For example, when the igniter is powered, should there be a 12V potential between the gray/white igniter wire -- the line for the neutral and sidestand lockout circuit -- and ground when the sidestand is down and the bike is in gear?

The bike had been running fine, but one afternoon I had a few of what felt like misfires and then the bike just quit. The starter spins the engine, but the engine doesn't fire. I've checked out the sidestand, neutral, kill, ignition and clutch switches, the sidestand relay, the ignition pickup sensor, fuses, the alarm bypass connector, fuel, ... and I'm running out of ideas other than the igniter. Unfortunately, the igniter is $714 on BikeBandit, so it's an expensive part to just order in the hope that it'll fix the problem.

Thanks in advance for any ideas.

[marcg]

Here's a picture of the igniter internals. I was hoping to find some smoked components for confirmation that the problem is indeed the igniter; there weren't any.

I'm still suspecting the igniter, even though I was able to get one weak cough from the engine by spraying starting fluid into the intake. There's plenty of fuel in the float bowls, so it's probably not a fuel problem. And I've now checked the ignition coils which are within spec. Also, when I open the throttle while cranking the engine the engine cranks faster, which makes me think that the problem is not an air blockage.

[tritonwow]

Did you pull your plugs to see their condition?
If they are wet after cranking then you know for sure you're getting gas (but may be flooded and why it won't fire).
Are they dry, pitch black-sooty? Might be the culprit of a weak spark. Check to see if you get spark with the plug out (research it first so you ground the plug while cranking and don;t spark leaking fuel)

[andrewb]

Judging by the photo of the back of the PCB, which the middle power transistor looks like it overheated and discolored the board, I'd try swapping out the ignitor.

The TIP x52 (can't quite read it ) transistor is common.

It's sometimes possible to rebuild these, but you need to find a shop that can test it after the work is done.

As for inexpensive, you can try Ebay (I've scored ignitors for less than $200) or I'd suggest Baxters Cycle in the US. You could also try Sprint Manufacturing in the UK.

Good luck,

Andrew

[SC SuperIII]

I tend to think that it's your pulser. There is a braided sheathing on the wire after it enters the case cover. It may have become frayed over time and covering your pick up as the wind from your crank spins the timing "puck" past the pulser. The sensor will read as correctly functioning, howver you won't realize this until you look. Besides, if you get spark and these problems you've mentioned then you igniter is working, but the timing is out (i.e. it's your pulser). Hey, correct me if I'm wrong.

[sailfish]

I have a friend with a 955 Sprint with a similar issue, no fire. More than one of us checked all of the cutout switches, clutch, side stand, etc. and all checked out. He ended up by-passing all of them and his bike started. There's a broken wire in his loom somewhere.

[marcg]

Thanks for the responses.

It's not the pickup coil. That's what I had initially assumed since I'd had one go out on me before and the symptoms were identical -- engine suddenly dies, tach drops to zero even with engine still spinning while I'm coasting in gear at 70 mph -- except that I was never able to get the bike to restart this time (with the bad pickup coil, the bike would restart once the engine cooled). So I ordered and installed a new coil and that's what's on the bike now.

I've bypassed the neutral and sidestand lockout switches, to no effect. I haven't bypassed the clutch switch, but I have verified that it prevents the starter from spinning when the clutch is out. I've also checked the function of the ignition switch with a continuity tester while flexing the ignition switch harness and it checks out.

I'm going to pull and check the plugs this afternoon as suggested.

Does anyone know whether igniters from other model years for the carburated Sprint should work on a '98 California model Sprint? I'm thinking about buying this one: http://cgi.ebay.com/ebaymotors/ws/eB...AQ:MOTORS:1123

[KitNYC]

Originally Posted by marcg

<...>
Does anyone know whether igniters from other model years for the carburated Sprint should work on a '98 California model Sprint? I'm thinking about buying this one: http://cgi.ebay.com/ebaymotors/ws/eB...AQ:MOTORS:1123

Not quite as simple a question as you might think; could be a good excuse to de-Californicate your ride...

All of the 3-cylinder T3 igniters will swap & run, but redlines & various other things are different bike to bike. I'm pretty sure you have a blue-cam/Tiger/Cruiser motor in your bike, so swapping in the 49-state igniter would allow you an extra 1000 or so RPM before the limiter kicks in. You could swap in green cams & a 49-state airbox & roll with it, but that would be a bit pricey & quite labor-intensive. You could also just live with it & be careful not to run into the over-rev, or even live dangerously & revel in your new-found RPM ceiling 'til the motor blows...

Anyway, long story short: it ain't the right part, but it'll fit.

Cheers, HTH,
-Kit

[marcg]

Thanks, Kit. That was the info I was looking for on the igniter.

The bike does have the California (softer?) cams. I looked into changing them along with other California (mis)features including the airbox and various carburetor pieces when I first bought the bike. At this point, with ~85k miles on it, I'm just looking to get the bike back on the road with minimal expense.

Marc

[KitNYC]

If I was in your shoes, I would check with Baxter on Monday just in case. (They sell used at 50% of list, so should be $40-50 cheaper than Pinwall.) Failing that, I'd pick up that piece from Pinwall & be careful not to over-rev it.

Cheers, HTH,
-Kit