Oil Injection - Why don't we like it?

meatball

meatball

User Title Unavailable
Location
Maryland
95 percent of the guys here are running 701 two cyl yami based platforms, carburetered 2-strokes. Understandably, it is of course different on a DI engine platform. Which engine are your referring to exactly?
 
stx-di

stx-di

Location
Levittown New York
meatball said:
95 percent of the guys here are running 701 two cyl yami based platforms, carburetered 2-strokes. Understandably, it is of course different on a DI engine platform. Which engine are your referring to exactly?
Click to expand...

2003 1100 stx di:biggthumpup:

I just replace my oil pump and lines just for having a 100 hours plus on my ski.
 
mekanic305

mekanic305

Thanks for the rain in GA
Location
ATL, GA
The actual pump for the oil injection I believe is controlled by the rotation of the flywheel, at least on a kaw 650sx it looked like it was, like a screwdriver almost...which means that its basically impossible for it to fail, but like everyone has said its the other stuff you have to worry about.
 
WFO Speedracer

WFO Speedracer

A lifetime ban is like a lifetime warranty !
Location
Alabama
mekanic305 said:
The actual pump for the oil injection I believe is controlled by the rotation of the flywheel, at least on a kaw 650sx it looked like it was, like a screwdriver almost...which means that its basically impossible for it to fail, but like everyone has said its the other stuff you have to worry about.
Click to expand...

Do you have any idea how many of those old 650 pump tangs that I have seen twisted off? Yes they can fail and Kawi ate a bunch of engines when they did,they did change the design of the pump but I still have seen some of the newer pumps fail also.
 
mekanic305

mekanic305

Thanks for the rain in GA
Location
ATL, GA
wedoseadoo said:
Do you have any idea how many of those old 650 pump tangs that I have seen twisted off? Yes they can fail and Kawi ate a bunch of engines when they did,they did change the design of the pump but I still have seen some of the newer pumps fail also.
Click to expand...

I retract my statement then, I did not know that. :no:
 
McDog

McDog

Other Administrator
Staff member
Location
South Florida
What about the Clymer's manual claim that the pump will adjust flow according to RPMs. It says that you need different ratios for different RPMs.
I know nothing about this but I just read it in the seadoo manual I bought. Is it true or are they full of crap?
 
Matt_E

Matt_E

steals hub caps from cars
Site Supporter
Location
at peace
No, that's true. In fact, that's one neat advantage of the oil injection. It is metered, meaning that the ratio at low RPMs will be quite low (1:100? IDK) and in upper RPMS it gets higher.
 
meatball

meatball

User Title Unavailable
Location
Maryland
I dont think they added an exponential curve to it, I think it just means that at low RPM's you wont be getting the same amount of oil as you will at high RPM's, which means it will stay at 50:1 the whole time. It goes with the crank rotation, so incase that thing is engineered with some kind of varying gearbox or something I dont know about, the amount of oil it pumps is linear. Same way with premix, you are pumping 50:1 gas into the carb at all times, the oil pump of course has to vary the oil it pumps, otherwise, you'd get 50:1 at high speed, high-fuel consumption, and 20:1 at low speed.

I dont see how the ratio could alter itself unless the fuel exponentially increases or the oil pump is electronically controlled, and not directly linked to the crank.

I see a couple of people who use their oil tank for 100:1 gas, and they switch to it while idling in no-wake zones, but I see it as un-necessary, you wont notice a difference in switching to premix.
 
Last edited:
Matt_E

Matt_E

steals hub caps from cars
Site Supporter
Location
at peace
Matt_E said:
No, that's true. In fact, that's one neat advantage of the oil injection. It is metered, meaning that the ratio at low RPMs will be quite low (1:100? IDK) and in upper RPMS it gets higher.
Click to expand...

Eh....the above post made me realize my statement isn't correct...but I am pretty sure the Seadoo motors are indeed variable ratio. Their pumps are not gear driven, they are throttle driven.
 
Scorn800

Scorn800

Ride for life
Location
North NJ
Oil injection is fine for sit down. Most newer sit downs have to have oil injection.
I would never use it on a stand up.
 
Mouthfulloflake

Mouthfulloflake

ISJWTA member #2
Location
NW Arkansas
the factory Kawasaki 750 manuals state that the oil pump deliver between 50:1 and 200:1 I think.

Id have to look it up for sure, but they do for sure state that its a variable ratio depending on engine RPM.

the oil pumps from kawasaki and yamahas look like the same units, and they work the same way ( visually at least)

?

Not trying to argue, just relating some info I had stored back for some odd reason.



Matt_E said:
No, that's true. In fact, that's one neat advantage of the oil injection. It is metered, meaning that the ratio at low RPMs will be quite low (1:100? IDK) and in upper RPMS it gets higher.
Click to expand...
 
meatball

meatball

User Title Unavailable
Location
Maryland
I remember a big 7 page long argument thread about this over at good ole PWCT. Most of you will be happy to know that Bryan Glynn supports my position of it maintaining 50:1 throughout the RPM range. It ended in agree to disagree :biggrin:
 
You must log in or register to reply here.
Top Bottom