'86 V6 oil injection pump rotation

[Still Wet]

I am working on an '86 150 Pro-V
The original oil injection had been disabled and I have chosen to restore the system.
I purchased a used '99 injection pump and all new mounting hardware and shaft from Boats.net.
I could not get the system to inject oil, Being the season is over up north here I removed the injection pump to inspect it, all looks fine with it.
I then chose to bench test the pump and what I found is the the pump works fine when the shaft is spin anti-clockwise. the interesting part is the shaft in the engine spins clockwise.

Did the rotation change when the system got upgraded in 1990 and a special pump is required for retrofitting the early engines?

[Inducted]

I think after 1989 yamaha switched pump manufacturers They switched to mikuni pumps which rotate clock wise. your shaft is probably updated(cw) I think you need an updated pump. Also the you might need a different check valve set up I think that changed too.

If your pump works ccw maybe an old style ccw shaft?

[Still Wet]

I did change the check valves as well, basically everything from the bottom of the oil tank to the intake nozzles.
Visually the shafts have the same gear on them as far as I can tell. This is from looking at all the shafts listed on ebay and checking the part numbers for there application. From this it just did not look like there was a change in the drive rotation but I have just now looked at the drive gear PN interchange and there is clearly no interchange before and after the '89-90 design change.
I thought I had research this well but clearly not well enough.
So it looks like the proper pump needs to be purchased.

Thank you for confirming the rotation change.

[ausnoelm]

it seems pretty strange that the pump rotation would change, it is driven by the engine which rotation has never changed, ever, so unless someone made a pump that had another set of drive gears internally (which would be easy to see in the parts diagrams) I am not to sure about the pump rotation changing, are you sure about what is stated?

[Still Wet]

I also would not have expected the rotation to have changed. It was only after installing the later pump and not being able to get it to bleed did I start researching this. The part that finally made it clear is the drive gear that goes on the crankshaft shows one gear fitting '84-89 and another PN for '90 on. A clear delineation of change, If that change was rotation direction and not a ratio change.
But I do know the pump is directional, it has internal porting in a piston and if you spin it one way it pumps great, spin it the other way it pushes the oil back out the inlet.

[ausnoelm]

there well may be a chnage in part numbers (for a variety of reasons) but the motor is still turning the same way, we need to find rodbolt (anyone know where he is yet?) for the definitive answer to this, now this may be a long shot, but you did assemble the one way vlaves the right way round?

[99yam40]

Rodbolt quit posting here and anywhere else that I can find.
I did hear he was alive and well, but I have no idea why he stopped.
So we will have to depend on other Yamaha techs from here on out

[Still Wet]

there well may be a chnage in part numbers (for a variety of reasons) but the motor is still turning the same way, we need to find rodbolt (anyone know where he is yet?) for the definitive answer to this, now this may be a long shot, but you did assemble the one way valves the right way round?

This has nothing to do with the check valves when bench testing.
And yes the motor still turns the same way but it is appearing the pump shaft rotation was changed.

I did take the new pump apart to see what makes it tic, or in this case squirt. The cylinder that does the work both spins and plunges. It is ported on the outside. As it spins these ports line up either with the inlet or one outlet at a time. When not running, no fluid can flow or weep through the pump as was the case with the old style pump that relied on internal spring loaded valves.

Having read Rodbolt's posts from the past I sure wish he was still active, I have learned quite a bit from his writings but I have allot more to learn.

[Inducted]

Personally I have never changed that style oil pump so I do not have any experience with your exact situation But I do remember it being a test question at tech school about the pump style change. You should call or visit your yamaha dealer and insist that they call yamaha parts and tech line .Yamaha has really good people and I'm sure they can solve your problem even if your local dealer is small and inexperienced.

[Still Wet]

One problem with being in Vermont is there are no dealers within a 2½ hr radius. The local small Mercury dealer says he will not touch a Yamaha, when I asked if he works on the four stroke Mercs he has been selling he was kind of vague. Not even sure I he knows the powerheads are Yamaha's.

So far between a this forum and a friend in Fla I have been able to find some bad intake check valves that were the idle issue and granted I could have left this engine running premix, I chose to bring the injection back to life. If I was not on a budget at this time I would have just bought the upgrade kit. I learn more this way and maybe reduce the chances of others getting caught up as I have doing the pump upgrade this way.