2002 DX150TLRA Ignition -Timing - Number of sparks per cylinder

[captainj]

I pretty sure the double spark was an issue with the tach I have. Seems to be picking up pulses from the other spark plugs. All sensors and TPS, CDI ouputs, or correct. The only thing that was close to failure was the sensor coils output manual says 16v min I am at 17v.
After running the engine for while and stop for an hour or so when restarted it would idle slower than it was supposed to be. Take off and run engine and back off to idle it would be fine. It happens when the warm engines sets a little while and when restarted is when the problem occurs. I list the things I have done in earlier post. I repalced the LP fuel pumps, they were not leaking though. Other post have said the have replaced when not leaking and have corrected their problems.
I checked the timing because the manual says it should be 3 BTDC so I checked it. It is correct on #1 but on the other five cylinders are on about 7 ATDC.
I have never seen different timing between cylinders before.
When engine is in cold start mode all cylinders advance to TDC and as engine warms up timing on #1 goes back to 3 ATDC and the other five go to 7 ATDC.
When the throttle is advanced the timing advances but they do not advance the same #1 cylinder is advanced more than the rest.
This may be the way it was designed. I thought maybe somebody may have seen this before. I just don't want to hurt the engine, this is the best outboard engine I have every seen. It has 3000hrs on it and the compression is still 120 PSI. and still runs like new except for the idle situation. It will blast off on hole shot and top end is still the same as it was when new.
I am going try and put it in the water in the next couple days and see what she does.
Rod don't get to upset with me. I just don't like not knowing why its this way
and if it something I should be worried about.

I really do thank everyone that is helping.

[99yam40]

this is a lot better explanation of what is going on.
but not sure how tach would show spark X2 unless you are seeing twice the PMs on tach

We just need someone with a motor like yours to check timing on theirs to see if it is the same,

did you index the other cylinders to check the timing on them?

Not that this will fix the idle necessarily

[captainj]

Yes the RPM's show double. But you are right all we need is for someone to check their timing to see if it is the same way.
Yamaha manual says to check timing with an erratic idle issue. I understand the idle is somewhat fixed as Rodbolt has said. But when the TPS is adjusted it advance or retards time at idle as it is adjusted. WOT timing is con*****ed by the ecm so it might be prudent to take out the timing light and check the timing to verify if the ecm is working properly. Who knows how many engines that get a hole in the piston is due to improper timing from the ecu if know body checks timing anymore. I don't think it matters why I checked the timing but I did. So lets answer the question is this normal or not. When I get back on the water I will be checking my WOT timing with a timing light.
I am hoping that the LP fuel pumps have corrected my problem. I was unaware of the timing till I put the light on it. I am just trying to find out if this is normal or not. Because I have never seen timing different between cylinders.
Thanks

[99yam40]

After running the engine for while and stop for an hour or so when restarted it would idle slower than it was supposed to be. Take off and run engine and back off to idle it would be fine. It happens when the warm engines sets a little while and when restarted is when the problem occurs. I list the things I have done in earlier post. I repalced the LP fuel pumps, they were not leaking though. Other post have said the have replaced when not leaking and have corrected their problems.
I checked the timing because the manual says it should be 3 BTDC so I checked it. It is correct on #1 but on the other five cylinders are on about 7 ATDC.
I have never seen different timing between cylinders before.
When engine is in cold start mode all cylinders advance to TDC and as engine warms up timing on #1 goes back to 3 ATDC and the other five go to 7 ATDC.
When the throttle is advanced the timing advances but they do not advance the same #1 cylinder is advanced more than the rest.
This may be the way it was designed. I thought maybe somebody may have seen this before.


Rod don't get to upset with me. I just don't like not knowing why its this way
and if it something I should be worried about.

I really do thank everyone that is helping.

I just reread this post and realized it is not #1 that is not in spec it is all of the rest of the cylinders that idle timing is not where it should be.

Yes WOT or full advance needs to be checked also to see what is hitting spec on them also if they advance different that #1 does.

Did you index the timing marks with TDC of the pistons to make sure the marks are correct on all cylinders?
Did you measure and mark the degrees on the other cylinders also or are you just guessing at the 7 degrees on them?

[rodbolt17]

did you check the injector timing?
the ECM controls injector timing and injector on time based on pulser coil and various sensor inputs.

[99yam40]

did you check the injector timing?
the ECM controls injector timing and injector on time based on pulser coil and various sensor inputs.

Interesting,
how do you check injector timing?
Special equipment?
Or will the old inductive timing light pick up the pulse to the injectors also somehow?

[captainj]

On the flywheel #1 and #2 cylinders are marked 30 BTDC to 10 ADTC. I just took a wooden dowel to check TDC it appears to be correct. I marked 10 ATDC with a marker and they are appear to be about 7 ADTC.

I don't how to check injector timing. Can you explain how to do it?

I did clean the stator, and the pulser coil towers they had some rust and corrision on them. I rechecked the pulser coil peak voltage output it remained the same 17v it had before cleaning.
Thanks

[rodbolt17]

no real way to check injector timing.
can it be done?
yes.
why bother it is fixed by the mechanical position of the pulser coils.

[99yam40]

no real way to check injector timing.
can it be done?
yes.
why bother it is fixed by the mechanical position of the pulser coils.

then why did you ask if he checked it?
The whole point of this thread at this point is why only #1 spark is following the spec on idle timing and is it normal for the others not to be at that spec

[pstephens46]

I had suspicions that there are two Rodbolts...hmmmm

[captainj]

Rodbolt, Are you here to help me are make fun of me. I don't understand why you want harp about me checking the timing. If there were a spec for injector timing I would have checked that too. You said that injectors was con*****ed by the pulser coils in your earlier post. So I knew that the pulser coil was con*****ing the injector timing if you were telling the truth then. But I think that the injector timing would be slight different than the spark timing. I would think that the injector timing would be in advance of the spark probably adjusted by the ecm.
If you are so smart why can't you just answer my question? If you are a master tech and you can't' answer it I guess its a pretty good question.

[99yam40]

I have noticed you have written BTDC and ATDC on different posts.
which is it? that is a big difference.

And if injectors fire after spark that would not work out too well in my opinion

[rodbolt17]

the Ox 66 uses both sequential and non-sequential injection.
normal running injector one fires #1 cyl and is the trigger signal for #2 injector.
#2 fires ign coil #2 and triggers injection for #3 and so on.
now at certain condition it also can use non-sequential or group injection.
this is strictly an ECU function.

you can test sequential operation,the injectors fire at 60* BTDC.

the DX150 is an odd animal,not many were made not many techs ever saw one.
I have worked on two.
it does have it's own manual and section in the tuneup spec guide.
does the ECU spark different cyl at different times?
it is entirely possible.

the ONLY spec published is for #1 cyl.
after that the only thing a tech can do is assume the ECU is working correctly.
ECU failure is incredibly rare on the OX66, I have seen 2 since about 1999.
myself I would use the diagnostic test lamp to see if the ECU is happy with all it's inputs.
use a DVM and check the O2 sensor outputs according to the latest tech bulliten.
then make sure the fuel pressure is correct at the failure RPM and load.

[captainj]

I couldn't find the error you are talking about. The only time I have mention BTDC was when the ecm was bypassed the timing went to 7 BTDC and when. I was telling what was marked on the flywheel.
The problem is #1 fires at 3 ATDC and 2-3-4-5-6 cylinders fire a 7 ATDC.

[rodbolt17]

it appears to be doing what it is supposed to do.
like I said there are no published timing mark references to any other cylinder.
the guide says 3*atdc +or- 2* at warm idle and 21*+or- 2* at full advance.