2002 V-Max HPDI

[gmerz]

I've got a 2002 V-Max HPDI 150 that I just finished break-in time on last fall before I put it away. Periodically the shift switch (mechanism that keeps the HPDI's on four cylinders at idle) has malfunctioned and the last two cylinders remained locked-out in gear which holds the RPM's to a max of 3,500 and fouls plugs quickly.

It's an intermittent problem that usually clears by shutting her down and restarting but a motor like this ought to run perfect. The dealer looked at it once and I got the usual "It ran fine for us..."

Anybody else experience this ??

[the little king]

I have a 2001 Vmax HPDI and have never had a problem with it. Its the best outboard I have ever had.

[Erich]

Our ski team ran several of them and had intermittent plug fouling.
Be sure your dealer checks the mechanical oil injection arm as well as the computer controlled oil pump. The shift switch may not be the culprit, the fouling may be happening regardless of the shift switch.
Our fouling did seem to go away after our oiler was adjusted and we got more hours on the motors and put brand new plugs in.

There is a lot of things that are different on the HPDI's from the OX66 EFI's, have your dealer call Yamaha if they are not 100% sure.

[gmerz]

The fouling is a kind of secondary problem. When the shift switch malfunctions, the motor will not climb past 3,500 RPM's no matter how far you push the throttle...

[lakeman]

common problem.....

throttle switch....

Bad on lots of big yammies last year.....

Intermittent problem........shutting off and on once or up to multiple times causes problem to go away....

Acts like it's a fouled plug but really just running on 2 cyclinders...

If you can't find a dealer close to you that will fix it....

Call 888-517-BOAT...... You can have them fix it or have them send you the part. Last year's motor is still under warranty.

Lakeman.

[PJM]

gmerz


I have run Yamaha's for years and it is my understanding the only the Saltwater series have the (CSS) Controlled Combustion System and not the HPDI. CSS is the system the six cylinders to four for low speed operation. I can't find anywhere in there in there literature that say's that.

[Erich]

I think it is one of those "undocumented" features. The HPDI's do shut down 2 cylinders, I think it is # 2 and 3 that are shut down, the difference is it is in neutral, not in gear like the 3.1 offshore motors that run on 5 and 4 cylinders depending upon rpms in gear.
I think another thing to check is that the shift cable is adjusted properly - if not the switch could remain engaged.

[gmerz]

Anybody know where I can get a service manual for a newer motor like this one ?

[Erich]

Your dealer should be able to order one for you - I am not sure that Clymer or anyone else has one out yet for them.