I got the little 250 into the shop to work on finally. Rebuilt the carb and put new crank seals in it. Has 125 psi for compression so the motor is fairly tight for it's age or had a top end done at one time. When I bought the machine and it ran when I went to look at it but just leaked gas at the carb. Now when I went to start it, I get nothing. Just turns over. I tested for spark because I had to fix a cobbled spark plug wire that the previous owner repaired and replaced the plug with a good NGK one. Nothing at the plug. I checked the wire and noticed it had a bare spot from rubbing so i checked it at the coil and still nothing. How do I check the coil to see if that's bad or where should I start to narrow things down or rule them out? I didn't look into the master kill switch on the left handle bar but I know I flipped it off and on right after I brought it home so maybe that is bad and I caused it by moving it.

Thanks,
Mike

 

Unless you have a coil checker like I had at the shop,resistance tests are what you're limited to. Most coils are basically the same on the older models. Coil tab to coil ground 0.3 ohms.Coil tab to wire(cap removed) 3.6K ohms. Resistor plug cap reading on the older ones, 3.7-6k ohms. Exciter coil Black/Red to Brown/White 120 ohms.Plus always unplug the black wire from the reverse limiter as they can cause problems. To isolate the cdi you can pull the black kill wire from it and see if you have spark. If you do then the ignition switch or left control switch or their wiring can be at fault.

 

Thanks OPT,

I pulled the wire on the limiter right away, something I do on all these older ones to rule out running issues. Tested to coil and came up with numbers similar to what you stated. Pulled the black wire on the cdi and still no spark. Do I test the stator wires next?

Thanks,
Mike

 

Yes, I'd check the stator exciter coil next. If it checks out, possible cdi fault. Plus on this if the flywheel and stator is all dirty and corroded that can affect spark even if the resistance shows good on the exciter coil.I'd pull the flywheel,clean and see if you then have spark.

 

Thanks OPT,

Here is what I have for numbers after I tested everything,

coil tab to coil ground- .3 ohms
coil tab to end of wire without cap- 5.937 ohms
stator black/red to brown/white- 115.6 ohms

This all looks good according to what I have in the service manual but still no spark. Black wire on cdi and reverse limiter unplugged. Pulled flywheel and everything is clean. I checked wires on the stator wire harness since I pulled the stator to do the crank seal but everything looks good. It had spark after I pulled the flywheel the first time so I don't think my moving the stator to get at the seal affected it. What's next? How do I test the cdi? I pulled the plug wire and cap from another running machine but that didn't give me spark either. If it is the cdi, will one off another 250 work in it to check it? I have a 94 or 95 trailblazer parts machine I can grab it off of to see if it will work.

Thanks,
Mike

 

Shows to be quite a few other year models that use the same cdi module along with yours.

Usage : 3083977
Year Product Model Assembly
2006 ATV TRAIL BLAZER MAGNETO - A06BA25CA (4994739473C08)
2005 ATV TRAIL BLAZER MAGNETO - A05BA25CA/CB (4994739473C08)
2004 ATV A04BA25CA TRAIL BLAZER MAGNETO - A04BA25CA/CB (4986208620C08)
2003 ATV TRAIL BLAZER 250 MAGNETO - A03BA25CA/CB (4975037503C08)
2002 ATV TRAIL BLAZER MAGNETO - A02BA25CA/CB/CD (4969896989C09)
2002 ATV TRAIL BLAZER FREEDOM MAGNETO - A02BA25CA/CB/CD (4969896989C09)
2002 ATV XPLORER 4X4 MAGNETO - A02CG25CA (4969856985C10)
2001 ATV XPLORER MAGNETO - A01AG25CA (4963866386C011)
2001 ATV TRAIL BLAZER MAGNETO - A01BA25CA (4963666366C010)
2001 ATV TRAIL BLAZER MAGNETO - A01BA25CA (4963666366C010)
2000 ATV XPLORER MAGNETO - A00AG25CA (4954865486C012)
2000 ATV TRAIL BLAZER MAGNETO - A00BA25CA (4954825482C011)
1999 ATV TRAIL BOSS MAGNETO - A99AA25CA (4949594959c009)
1999 ATV TRAIL BLAZER 250 MAGNETO - A99BA25CA (4949574957c010)
1998 ATV TRAIL BLAZER MAGNETO Trail Blazer W98BA25C (4945464546C009)
1998 ATV TRAIL BOSS MAGNETO Trail Boss W98AA25C (4945314531C009)
1997 ATV SPORT 400L MAGNETO (BLAZER) Trail Blazer W97BA25C (4940124012D011)
1997 ATV TRAIL BLAZER MAGNETO (BLAZER) Trail Blazer W97BA25C (4940124012D011)
1997 ATV TRAIL BOSS MAGNETO Trail Boss W97AA25C (4940574057C009)
1996 ATV SPORT 400L MAGNETO (BLAZER) - W967827 (4935863586D012)
1996 ATV TRAIL BLAZER ES MAGNETO (BLAZER) - W967827 (4935863586D012)
1996 ATV TRAIL BOSS MAGNETO Trail Boss W968527 (4935883588C009)
1995 ATV TRAIL BLAZER MAGNETO ASSEMBLY Trail Blazer W957221 (4930363036C009)
1995 ATV TRAIL BOSS 250 MAGNETO ASSEMBLY Trail Boss W958527 (4930323032C010)
1994 ATV TRAIL BOSS MAGNETO ASSEMBLY - W948527 (4926822682C007)
1994 ATV TRAIL BLAZER MAGNETO ASSEMBLY Trail Blazer W947221 (4926832683C007)
1993 ATV 250 2X4 MAGNETO ASSEMBLY - W937527 (4924042404036A)
1993 ATV 250 4X4 MAGNETO ASSEMBLY 4X4 250 W938127 (4924042404036A)
1993 ATV 250 6X6 MAGNETO ASSEMBLY 6X6 250 W938727 (4924092409044A)
1993 ATV TRAIL BOSS MAGNETO ASSEMBLY Trail Boss W938527 (4924072407031A)
1993 ATV TRAIL BLAZER MAGNETO Trail Blazer W937221 (4924082408031A)
1992 ATV TRAIL BOSS 2X4 MAGNETO ASSEMBLY 250 2X4/W927527 (4922862286038A)
1992 ATV TRAIL BOSS 4X4 MAGNETO ASSEMBLY 250 4x4 / W928127 (4922872287D004)
1992 ATV BIG BOSS 4X6 MAGNETO ASSEMBLY 250 4x6 / W928627 (4922902290044A)
1992 ATV BIG BOSS 6X6 MAGNETO ASSEMBLY 250 6x6 / W928727 (4922842284048A)
1992 ATV Euro Big Boss 6x6 MAGNETO ASSEMBLY 250 6x6 / W928727 (4922842284048A)
1992 ATV TRAIL BLAZER MAGNETO ASSEMBLY Trail Blazer / W927221 (4922852285036A)
1992 ATV TRAIL BOSS 250 MAGNETO ASSEMBLY Trail Boss / W928527 (4922892289038A)
1991 ATV TRAIL BOSS 4X4 MAGNET0 ASSEMBLY 250 4X4 - Update (4919791979046A)
1991 ATV TRAIL BOSS 2X4 MAGNETO ASSEMBLY 250 2X4 - Update (4919781978038A)
1991 ATV BIG BOSS 6X6 MAGNETO ASSEMBLY 6X6 (4919811981048A)
1991 ATV BIG BOSS 4X6 MAGNETO ASSEMBLY BIG BOSS 4X6 (4919801980042A)
1991 ATV TRAIL BLAZER MAGNETO ASSEMBLY TRAIL BLAZER (4919761976038A)
1991 ATV TRAIL BOSS 250 MAGNETO ASSEMBLY Trail Boss - Update (4919771977038A)
1990 ATV TRAIL BOSS 250 Magneto Assembly (4917711771038A)
1990 ATV TRAIL BOSS 2X4 Magneto Assembly (4917721772037A)
1990 ATV TRAIL BOSS 4X4 Magneto Assembly (4917731773046A)
1990 ATV BIG BOSS 4X6 Magneto Assembly (4917741774041A)
1990 ATV TRAIL BLAZER Magneto Assembly (4918411841036A)
1989 ATV Big Boss 4x6 Magneto Assembly (4915951595041A)

 

Thanks OPT,

So if everything checked out, then it should point towards the cdi? Funny that it just went out just like that but I guess stranger things have happened. I can try a used one off of a parts machine before I spend the money on a new one.

Thanks,
Mike

 

If you have one that will interchange,slap it on and see if that solves the problem.Sensitive as they are,a cdi can go out just as fast as a light bulb.Plus hate to recommend some of the aftermarket ones,but plenty of them low as 14 bucks.

 

Well, I went out to check on one of my parts machines buy no dice on a cdi. Looks like it was robbed off of it before I got the machine. Oh well.

Is there a way to test a cdi? The service manual has everything pertaining to the coil and exciter coil but no specs for the cdi itself other than to unplug the black wire to rule out the kill switch and ignition switch. I guess if everything else specs out it can only point to the cdi but I just want to be sure before I order a new one for it. This machine is just going to be a cabin four wheeler to do small jobs at a cabin and let the grandkids putt around on it so it's use will be limited to say the least.

I'm trying to finish this one up fairly quick because I'm in the middle of buying a new house. Currently the house I'm in has limited garage space so the wife gets to park there and all the old polaris four wheelers get put in storage when not in use. When I work on a project I am doing it at the shop i work for so space is tight there too. The new house has a nice big two car garage attached to the house so the wife is happy and it has a real nice large heated shop in the back yard so I have my man cave to do what I please with all the old two strokes I find now. There is even a small work shop in the basement that I can use for my upholstery work. I do a lot of four wheeler seats and now I have a spot to do them without any clutter. My wife isn't really sure this will all be a good thing because it will be hard to find me around the house now but I guess I don't like watching football or like to gamble so if the only bad habit to have is tinkering with old four wheelers it can't be all that bad, lol.

Thanks,
Mike

 

Forgot about the 2003 Trail Blazer showing voltage tests from the exciter coil and the cdi module. It uses the same electronics as your 89 model. How's that for longevity on using the same parts for different year models.

Disconnect the stator connectors from the CDI
module. Test output from exciter coil, pulse (trigger)
coil, and compare to the chart. The following
measurements are obtained when cranking the
engine with the electric starter, spark plug installed.
The starter system must be in good condition and the
battery fully charged.
150 Watt 2 Stroke
Coil Connect
Meter Wires
To:
Reading
With Peak Reading
Volt meter
Exciter Black/Red
Brn/White
130 DCV
CDI OUTPUT TEST USING
PEAK READING ADAPTOR
Re-connect all CDI wires to stator wires. Disconnect
CDI module wire from ignition coil primary terminal.
Connect one meter lead to engine ground and the
other to the ignition coil primary wire leading from the
CDI module. Crank engine and check output of CDI
wire to coil (130 DCV). Reconnect coil wire to CDI.
Output w/ Peak output tester
130 DCV
Average Output w/ Digital Voltmeter
20 DCV