1994 Yamaha 2strk 90hp TLRS no ignition when crank position is plugged in

[the Macheen]

1) with all components hooked up and spark checker in place 1&3 will fire
about 2 revolutions and quit. engine starts and cuts off
a. disconnect boat harness from engine using jumper wire at solenoid to
crank engine with same results.
2) disconnect Crank Position at CDI box and engine has continuous fire on 1 &
3. With boat harness reconnected starts on key and shuts off properly.
a. connect crank position while running and shuts off engine completely
3) thinking crank position was bad i replaced it and still have same problems
4) i have performed DVA test per Yamaha and CDI manual
a. pulser coil - calls for 7V unloaded i got 12v -----loaded calls for 5v i got
8.7
1) ohm check calls for 220-270 i got 294 i believe to be within 10% and
feel it's ok knowing temp and other factors can effect readings
b. Charge coil -
1) brown to red unloaded calls for 90v i got 93 -----loaded calls for 60V
i got 107 with CP disconnected and 83 with it connected
a. ohm check - book says 191-288 i got 84
2) blue to red unloaded calls for 90V i got 150v --- loaded calls for 100
i got 156 with CP disconnected and 124 with it connected
a. ohm check calls for 70-90 i got 235
the ohm readings seem to be backwards and i wonder if this is a misprint in both the yamaha and cdi manuals - i know CDI will reprint Yamaha specs from their manuals

Crank position calls for 5.5v unloaded i got 5.5 ---they call for 5.5v loaded i got 5.7v

i know the CP sensor triggers the #2 cylinder and it should be on by 1500 rpm and you won't see any spark on #2 when cranking with spark checker. but my issue is with CP connected i have momentary fire on 1&3 and that's all

Has anyone experienced this problem - i found an old thread but where it ended there wasn't a solution. any help would be greatly appreciated.

Michael

[rodbolt17]

your specs are off.
that's why I try not to use aftermarket specs.

the voltage spec given in the Yamaha and the Yamaha tune up spec guides are minimum voltage specs.
did you try the CDI output test and the ign coil primary and secondary resistance tests?

if the above pass then I would suspect a CDI failure.

[the Macheen]

Rodbolt can you help

Rodbolt i appreciate you taking the time to look at my problem as you seem to be quite versed in Yamaha repairs

to further clarify i do NOT have a tune up spec guide for Yamaha's

i am however using a Factory manual and i performed the following test today using a ANALOG METER set to 1K.

Resistance test on the CDI - I too am in NC (Lake Norman) temp today during test was 55 degrees

Charge coil ohm ck were in specs except for the Ground to Brown, RED, & Blue on each check the reading was about 3K ohms over the max in the manual

Pulser coil - all checked good except for the Ground to the W/R and W/B and each of these were about 3K ohms over the max

i tested each coil removed from the engine and all 3 read the same
Primary .2 ohms - i backed this reading up with a Fluke since the resolution was very low on the analog

secondary coil -- i removed all three plug wires from each coil and all checked @ 4.1K ----each wire checked @ 5k and each coil with high tension lead screwed back in checked at a total of 9K. my manual shows a picture checking the Ohms from ground to the end of High Tension lead and the maximum to be 4.9k ???? past experience tells 9K isn't too high and they are all the same

Rodbolt is it possible for you explain how to do the output checks on the CDI and can you post or send me the Tune up specs for this engine?

I went back and rechecked my resistance readings on the charge coil with the analog meter and got the same as I posted earlier - it's like their reversed however i understand the stator could be bad and this is my problem.

Have you ever had this problem before? I appreciate your help and look forward to your next post.

[rodbolt17]

pulser spec,300 ohms+ or - 20%.
voltage loaded cranking,5
unloaded 7
1500 14
3500 20.
these are minimums.

charge coils red to blue,240 ohms.
cranking 60v.
1500 170v
3500 150v.
brown -red
80 ohms
100v cranking
90v unloaded
1500 135v
3500 135v
cps 197 ohms
cranking loaded and unloaded 5.5v
1500 2.5v.

all voltage specs use a peak reading meter or a DVM with a DVA attachment.
a standard digital or analog meter will read lower.

[the Macheen]

Cause found and repaired

My procedures for checking all outputs were done correctly using DVA.

Some of the readings i got were different than what was in the book because the book has the wrong specs printed in it.

I replaced the following parts in this order because it seemed the most logical.
1) crank position - still same problem
2) Crank trigger/pulser coil - same problem
3) CDI unit - same problem
4) Got Yamaha involved -they said to put stator on it - replace stator - same problem - Yamaha tech help is not the greatest - some of them have attitudes like everyone in the field is a dumbass -
5) Flywheel replaced - problem resolved
how the flywheel went bad i do not know as all the magnets are encased
and Yamaha never raised the possibility the flywheel may be a problem.
i guess the experts aren't always experts.

[boscoe99]

Yamaha data is notorious for being incorrect, insufficient, sub-standard.

If you call Yam US customer support more than likely you did not talk to a technical guy. More than likely you talked to a guy that has never worked on a Yam or any motor.

Yam US is reluctant to give out technical support because if a backyardigan screws something up he will blame it on Yamaha.

Then too, some folks calling Yam for technical help are not even qualified to be the screwdriver holders assistant.

Yam expects owners to take their motors to dealers.

Now in Yams defence, they get a lot of dumbass calls. Some even from their dealers mechanics. The marine industry is a strange one, IMO.

[99yam40]

My procedures for checking all outputs were done correctly using DVA.

Some of the readings i got were different than what was in the book because the book has the wrong specs printed in it.

I replaced the following parts in this order because it seemed the most logical.
1) crank position - still same problem
2) Crank trigger/pulser coil - same problem
3) CDI unit - same problem
4) Got Yamaha involved -they said to put stator on it - replace stator - same problem - Yamaha tech help is not the greatest - some of them have attitudes like everyone in the field is a dumbass -
5) Flywheel replaced - problem resolved
how the flywheel went bad i do not know as all the magnets are encased
and Yamaha never raised the possibility the flywheel may be a problem.
i guess the experts aren't always experts.

Did you replace the flywheel or did someone else do it for you?

Maybe something got moved around and cured a bad connection

Hard to figure what was wrong with a flywheel to have spark for just a short time like that and then nothing