active cylinder management?

[b.gagnon]

2000-2001 150 HPDi Yamaha....(new to me)

Does this motor have active cylinder management?
My bottom port cyl has 93psi and bottom starb has 90.....The rest are 110-115. The motor runs great, just wondering if that is normal?

 

[b.gagnon]

Maybe I should be more descriptive..
Does the motor run on 4cyl @ low RPM? And does it have a different compression ratio for the bottom 2 cyl's ?
Thanks...

 

[99yam40]

may need to locate a Yamaha master tech to give you the info you are looking for.
do a web search for Rodbolt 17 to find the forum he posts in now a days.
The HPDIs did drop cylinders under certain conditions usually in neutral

 

[tommarvin]

Im asking, is compression, compression. Two low cylinders ? My crabbing bud has a yam.

 

[b.gagnon]

From what I can tell...
Yamaha has run different compression ratios between cyl banks on some v6 motors. That could cause each bank to have different compression on the same motor.
I hope my motor is one....Otherwise I am in trouble!

 

[b.gagnon]

I found a manual and the motor does have two different compression ratios....
1-4 = 6.7
5-6 = 6.4
I'm not sure how that relates to pressure....

 

[tommarvin]

My crabbing bud has a 2006 90hp, he plugs his laptop into his motor for diagnostic and maintance, he had to buy software to do this, do you do this too?

 

[b.gagnon]

Yes, I have the cable and software but it doesn't tell you that kind of info...

 

[99yam40]

do as I recommended earlier to find some one that works on these motors all of the time,

 

[b.gagnon]

I did a search for rodbolt...but cant find anything recent. It seems he posted at The Hull Truth but not for a while!

 

[99yam40]

Did you do a search for Rodbolt17?

 

[b.gagnon]

Found him on the Yamaha Parts forum!
Thanks...