Yamaha part number convention question

[fairdeal]

So, I came across this statement in a Yamaha publication:



The publication also explains that the "Design Code Number":

***-***x-Xx-xx

"separates like component parts from one another when specification differences are involved."

Now, specifically for the ECM on the F225,
here's what the "GENUINE YAMAHA Parts Lookup" at yamahamc.partsandwarranty.com
says about the history:

F225TXR 0410 69J-8591A-33-00
F225TXR 0406 69J-8591A-32-00
F225TXR 0405 69J-8591A-31-00
F225TXRD 69J-8591A-30-00
F225TXRC 69J-8591A-10-00

Based on the above description of the way Yamaha uses their part number system,

a -10 ECM could not be replaced by any -3X ECM - because the "specification" is different.

However, if the -30, -31, -32, and -33 are NOT different from each other in "specification" -

but ONLY in "durability, quality, appearance or cost" -

then are they not only "backwardly compatible" - but also "interchangeable" ?

That, although the -33 represents some form of "improvement" over the -30;

the -30 could be used /"would work" on any F225 made between 2005 and 2010?

[99yam40]

It sounds like that could be true, but if your motor came with an up graded ECU and you put an earlier one on it,
it may have problems that they corrected with the newer ones.
you never know what the upgrade was or did

[fairdeal]

It sounds like that could be true, but if your motor came with an up graded ECU and you put an earlier one on it,
it may have problems that they corrected with the newer ones.
you never know what the upgrade was or did

certainly. Actually, I happen to know of one difference from "-30" to "-31" :

the addition of "Command Link" communication.

But Yamaha seems to have made some distinction as to the "seriousness" ?

of the changes -

or why would they have not changed the "-3x" to "-4x" "-5x" etc?

I'm hoping the esteemed Boscoe will clear it up for us!

[boscoe99]

Fairdeal, Fairdeal, Fairdeal. You bees a thinking man. I like that.

Not esteemed but here I are.

Yamaha uses what they refer to as interchangeability (I/C) codes for part number changes. A, B and C.

A means a new part can be used on a new motor or an old motor. Or, the old part can be used on the new motor. Fully interchangeable parts. No restrictions whatsoever. Say there was a connecting rod improvement and the rod is coded A. Improved rod can be used in the new motor or the old motor or the older rod used in either the new motor or the older motor. Yamaha will only stock the new part and that is what one will get even if they are rebuilding an older motor.

B means older part number used in the older motor. New part number to be used in either the older motor or the newer motor. But the older part is not to be used on the new motor. Yamaha will only stock the new part and that is what one will get even if they are rebuilding an older motor.

C means no interchangeability at all. Older part for older motor and newer part for the newer motor. Yamaha will stock both the older part for older motors and the newer part for newer motors.

A number change in the third from the last number code -01-00 generally means the I/C is new for old. If the number change is in the fourth from the last number code -10-00 it usually means the I/C is C, no interchangeability. However.

Let's look at an early F250 lower unit. Part number of 6P2-45300-20-8D. That lower unit has a single pair of water inlets. Later F250 motors came with lower units that have two pairs of water inlets. 6P2-45300-40-8D. Both parts are available from Yamaha. Yamaha does not consider them to be interchangeable. But, in fact, either lower unit will work on either older or later motors. I strapped a later model F250 lower unit on my F200 and it worked just fine. But ask Yamaha and they can't and won't tell you that it OK to use either the early or the later F250 gear cases on an F200.

[fairdeal]

Excellent. Thank you very much.

I read it several times to make sure I got it.

But once again, your explanation is clearer - and more informative -

than that printed by Yamaha....

[boscoe99]

By the way, the exact same methodology was used when I was in the air plane business with a slight variance.

A1 One way. New for old.
B2 Two ways. New for old and old for new.
CO. No way.

[rodbolt17]

but then, Boscoes example of the gearcase swap.
now the next technician 8 states over that is a newbie that only does service work gets it in for a simple water pump change.
now its all reassembled JUST like the service and parts manual says for an 05 F250.
now it overheats.
maybe that new guy did not realize the rubber dam under the wearplate must be there on the dual water pickup case and the parts diagram for the F250txrd failed to show it so it got left out.
same as a 1995 150 txrt gearcase will fit a 1994 txrs.
the pump housings wear plate and insert wont work if you looked a kit up for the 1994 model.

so in the eyes of Yamaha they list them as a C interchange.

[boscoe99]

but then, Boscoes example of the gearcase swap.
now the next technician 8 states over that is a newbie that only does service work gets it in for a simple water pump change.
now its all reassembled JUST like the service and parts manual says for an 05 F250.
now it overheats.
maybe that new guy did not realize the rubber dam under the wearplate must be there on the dual water pickup case and the parts diagram for the F250txrd failed to show it so it got left out.
same as a 1995 150 txrt gearcase will fit a 1994 txrs.
the pump housings wear plate and insert wont work if you looked a kit up for the 1994 model.

so in the eyes of Yamaha they list them as a C interchange.

Yes. Absolutely. Heaven forbid that Yamaha actually provide suitable service data for the less than top of the line Yamaha mechanics that know what they are doing. Wiring diagrams are the absolute worst. They are getting better as new SM's get issued but there are not corrections to past crap data.

But if a user does a configuration change then shame on that user if he does not let the mechanic know what has been done to the motor. The user more than likely will blame the mechanic when something goes amiss because of a component that was not reassembled properly. Because he forgot to tell his mechanic.

[rodbolt17]

most times the user bought it that way and has no clue.
I see it all the time.
will it work? yep if you know what your looking at.
kinda like using the latest 6Y5 tach on an 03 motor.
can I make it work? yep .
good luck with the next guy trying to troubleshoot it if the next guy doesn't understand how and why it works.