TBM flywheel kicking my butt

Last year I bought a TBM flywheel. I bought the special one that is supposed to be compatible with the Advent ignition.

I didn't install it until I got my Lamey. When we encountered some running problems I checked timing and found out the Advent was WAY too advanced, like it idled at 35 degrees and advanced from there. Sometimes it would actually start BACKWARDS.

I swapped back to the stock flywheel and it was still too advanced. In retrospect I KNOW the Advent worked fine with my lightened stock 62T flywheel earlier in the season because I had tested it on my Team Scream engine. So now I am thinking the TBM flywheel DAMAGED my Advent permanently.

So fast forward to this year. I bought a Vilder ignition because the curve is programmable and I thought if the timing was too advanced (or retarded) that I could advance or retard the sync setting with my laptop and get it perfect. I got my ski started yesterday....

for about 6 seconds.....

Then it died and never produced a spark again. My guess is that the TBM has fried my Vilder ignition too.

Anyone else experienced CDI failures after installing TBM flywheels?

Aaron
 

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I haven't had any problems with mine at all. Perhaps you could compare it to another to see if it was manufactured wrong, but even then it should simply not work, not damage cdi's.

Has this engine ever ran in this configuration before? I only say this because you have now tried 2 different ignition systems with this engine configuration and are still having problems. I see how you would think that the only common denominator is the TBM but if i'm not mistaken then this is a new crank in a new engine? Have you verified the alignment of the keyway in the crank to TDC. It just sounds to me like there is something else wrong.

Do you have a stock ignition to try?

It's going to be something simple and easily overlooked.
 
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tbm strikes again?
not saying it's impossible but i doubt the wheel would damage the cdi's.
sounds more like the crank may be offset.
 
I verified the crank pin location last year. It's all good.

I had the timing light hooked up while I was cranking the motor over yesterday. Before it started it was flashing and indication about 18 degrees of timing. So the Vilder was working before the engine started. It took a bit to get fuel into the carbs, then fired up...and died. Lost spark. Never got it back.

I've got another Vilder, a stock CDI, a MSd enhancer and a stock flywheel all to try out.

Aaron
 
Yes, the stator is in the right spot. I verified timing against what the Vilder was programmed for while I was initially trying to start it. (Timing lights are a great PAIN FREE way to test for spark).

I have a cut up flywheel cover that allows me to turn the engine over and even run the ski with the flywheel exposed. I verified TDC and made a 0 mark, then I used a degree wheel to make a couple other marks (10 and 20).

When it was cranking (but not starting) I saw it flashing between the 10 and 20 marks..closer to the 20. And sure enough the Vilder was programmed for 18 at low rpm. So it all seemed great...until it died. haha.

Aaron
 

madscientist

chilling with these guys.
Location
good old p'cola
sounds like a ground problem. add a secondary ground from the head to the battery and a third from the vilder. the small gauge wire they rely on for operation has a tendency to go bad.
 
vilders are picky with the wheels but they still run ,just timed differently.
the advents were known for breaking down a while back but have since been reliable.
how old is your advent?
checking timing while cranking is iffy at best with pretty much all aftermarket cdi's
put the oem wheel and cdi first to eliminate problems one at a time.
 

Matt_E

steals hub caps from cars
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at peace
It is extremely unlikely that the flywheel would damage the ignition at all, let alone influence it in such a way as to retard the timing by a certain amount.

I'd look elsewhere.
 

keefer

T1
Location
Tennessee
Yep, all it is doing is passing a small magnet past the pickup to provide a pulse. I agree that there is a bigger problem with bad grounds or other points of failure.
 

Waternut

Customizing addict
Location
Macon, GA
Sometimes it would actually start BACKWARDS.

I haven't read this whole post but that sentence right there says that your wiring is screwed up. The only way the engine can spin backwards is if your starter is wired backwards and your bendix is screwed up as well. The starter can run backwards if you reverse the wires. However, the bendix shouldn't be popping out if spun in the wrong direction.
 

Matt_E

steals hub caps from cars
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I haven't read this whole post but that sentence right there says that your wiring is screwed up. The only way the engine can spin backwards is if your starter is wired backwards and your bendix is screwed up as well. The starter can run backwards if you reverse the wires. However, the bendix shouldn't be popping out if spun in the wrong direction.

Sorry, not quite right.
Even though the starter spins it in the right direction, if the timing is too far advanced, the engine can and will run backwards.
I've had that happen personally.

The starter only gets it going - if the ignition fires too early (and both plugs fire at the same time!), it will kick the engine into reverse.
 
I haven't read this whole post but that sentence right there says that your wiring is screwed up. The only way the engine can spin backwards is if your starter is wired backwards and your bendix is screwed up as well. The starter can run backwards if you reverse the wires. However, the bendix shouldn't be popping out if spun in the wrong direction.

say what?
 

Matt_E

steals hub caps from cars
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It would happen after a sub or a stab....I'd come back up and the engine still ran, but sounded off. I would gas it, the engine would rev up, but absolutely no output from the pump.
I had to turn it off, and restart.
Problem solved.
 

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Not to get off topic but look up RER on skidoo's they figured out how to stop the engine and kick it in Reverse with Timing. They shaved 28 lbs off a skidoo by running the engine in reverse instead of using any gearing to accomplish it. Pretty cool concept actually. No added stress on the engine either.
 
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