1990 yamaha 130hp bogging down... need help with ignition troubleshoot....

[fmt2bx]

Hi,

This is a 1990 130ETXD. I have the yamaha service manual.

-Starts ok
-Idle fine (for long period of time.
-Tach gauge stable at 700 RPM at idle

When giving it WOT, revs normally to about 5100 to 5300 rpm then goes down to 4500rpm at wot.

What I have done so far:

Rebuilt carbs (3 times :-/ )
Ran from portable tank
Replaced fuel pump
Change thermostats
Squeezed primer, no difference
squirt fuel in carbs, no difference
Replaced all fuel hoses
Bypassed the fuel quick disconnect

I really thought that it was a fuel issue, but nothing has made any difference so far. So I am checking ignition:

I have found a bad reading of Secondary coil resistance on 1 coil, turn out the spark plug connector/coil wire was faulty. Fixed that. No difference.

Now I am having trouble reading the stator resistance.
I removed the stator plug going to pack, nothing between Brown and Blue and nothing between Red and Black and Red.
I tested and re-tested my multimeter, tried different Ohm scales, even borrowed my neighbor multimeter and still nothing.
I am not reading any ohms at the stator (???)

Would that motor even start under these conditions?

I am probably doing something wrong here,

Thank you.

Fmt

 

[fmt2bx]

If there is no resistance reading on a stator (going to charge packs) would a motor even fire up and run?
Anyone?

Thanks

 

[99yam40]

Are you saying you have 0 ohms or infinity?
what does the service manual say those reading should be?

are those wires for the low speed charge coil or the high speed charge coil,if it has those?

using a DVA adapter and peak voltage reading on all inputs and out puts of the CDI would be what I would try next
loaded and unloaded

 

[fmt2bx]

Hi and thank you for your reply.

The stator has 2 sets of coils,
one the lighting coil (battery charger) this one reads 0.5 Ohm, service manual says {0.288 and 0.432}
The other is the CDI charging coils (2 sets). I read infinity at both and manual says [55-83 ohm] and [582-888 ohms] respectively.

The service manual doesn't give any DVA specification, just resistance. (?). I found some info on the web from CDI electronic but not sure if they are accurate for Yamaha original electronic components.

I'll check what value I get with the DVA and post them here.

Thanks