Yamaha F225. Timing belt and ignition timing question.

[pmpvl1986]

Hi, friends,

I try to check ignition timing with timing light (strobe) as specified in workshop manual, but got a strange thing: 1 cylinder blink as . ... . . ... .. .. . ... ... .. . . . . . .. . .. at idle, when i adjust rpm it blinks smth. like . .. ....... .. .... ....... .. . ...... It looks chaotic. When i check 2 cylinder it blinks just as any other motors i checked previously like ........................... The same thing happen at 3,5 and 4,6 cylinders.
I've replaced ignition coils to check whether it's similar and they show same effect.
Might be it's OK for yamaha to pass some ignition moment?!

Also i checked timing belt and it looks like it's sagging even when tensioner it "on". But when i start to rotate manually it becomes strain again.

Best Wishes

[ausnoelm]

Do you have a problem with the motor, or are you just checking the timing for fun?

[pmpvl1986]

I've got several pistons damaged recently in case of bad fuel usage, so engine was completely repaired.

So it's just a check list from Yamaha sevice manual for initial 10 hours idle work. Ignition timing needed to be checked. But on all other engines I had strobe light always made blinks like ................. So "tdc" or "zero" mark easily viewed, but here with chaotic blinks at first cylinder it's even hard to see control mark.

Attached pic of a process

[TownsendsFJR1300]

Just for S&G's, can you put your timing light on another engine (car, mower, etc) just to confirm it's NOT the light?

[pmpvl1986]

That was the first thing i've done. I went to my car to check whether my v6 will show me the same picture. Nope...

Also if it's a "light" then it'd show same blink on every cylinder, but it show different pictures on one "head" and other on another.

Next thing was changing coils and spark plugs. Also same effect.

BUT. What is strange. When i attach "light" sensor:
to ignition coil - .............
to left "head" spark wire - ............
to right "head" spark wire - . .. .. .... . .. . . .. .. ...... smth. like that.
to right "head" spark wire when
it's quite detached from spark plug (a knock of spark could be heared - ................

So it become unstable only when spark wire attached completly to spark plug. Changing spark plugs from left to right didn't help.

[TownsendsFJR1300]

I'm not familiar (and don't have a year/ model # to check the parts fisch) for your engine but can that coil wire remove from the coil for checking resistance/arcing?

Thinking out loud, if that spark plug wasn't firing all the time (perhaps no ground with the plug-bad plug), would you get a signal thru the wire?

Again, for S&G's, perhaps swapping plugs and then checking each cylinder and see if the issue follows the plug..


IDK about PU coils, etc, so Rodbolt, Boscoe or someone else will have to chime in...

[pmpvl1986]

As I can see coil wires are not removeable. There is a procedure to check whether ignition coil is "ok" or "not". I'm not so familar with digital tester, so just changed several coils for parts from my partner shop. So 3 mine coils and 6 (2 sets) from his show same thing. So it's quite impossible that problem could be in coils.

Based on your thoughts, it looks more like that there is a bad groud at the second cylinder head... Or even short circuit.

Nope... Changing plugs and even changing coil wires (from left to right side with upside down position of coil) doesn't effect on what happen with timing light of right "head"...

But, anyway, it seems that this situation isn't usual? ) Our Yamaha dealers can't say anything

[99yam40]

Rodbolt17's or Boscoe99's help is needed on this.

I would think checking the inputs to the coils is needed, but I have no idea what kind of ignition system this motor has

[pmpvl1986]

Might be it'd help. It's Yamaha 2003 F225TXRB

[TownsendsFJR1300]

Rodbolt or Boscoe will chime in eventually..

I suspect RB is busy as he was in the general path of "Matthew" and works in a marina...

[throrope]

How old is the timing light? I recall the old ones can't be used with the new ignition systems.

[99yam40]

my old 70's Snap On worked fine on my C40 once I clipped it on with the arrow pointed away from the Spark plug( opposite the direction it was suppose to go)

[pmpvl1986]

My friends...

There is no matter how old is timing light. It just show electric impulses. Mine was purchased half an year ago and no other engines show me such strange picture.

Also if it doesn't work then all 6 wires should show equally chaotic, but it 50/50...

Also ignition coil get impulse and pass it to 2 wires to 2 cylinders. it just split signal to fire 2 cyliders at once. So I think that problem not with coils, but with smth. that "block" or "fade" signal on right cylinder head...

[99yam40]

My friends...

Also ignition coil get impulse and pass it to 2 wires to 2 cylinders. it just split signal to fire 2 cyliders at once. So I think that problem not with coils, but with smth. that "block" or "fade" signal on right cylinder head...

I am not sure what the word smth you write is

If you or the guys working on this motor have the service manual for it , it should show how to test the ignition system it it with the specs

Still need Rod or boscoe to come in with some help with what ignition system this motor uses.

[pmpvl1986]

Smth. - something :-)