90hp autolube oil consumption

[Searider]

Hi folks ,
After I solved the issue with my stator my 90hp works very well .
I was with my RIB on a sea trial today and burned 45 liters of fuel . Due to rough sea conditions I was mostly at 3500 rpm only .
Back at home I checked the oil tank and added exactly 1 liter of 2 stroke oil .
This is my first 2 stroke engine and thats why my question - is a 1:45 mixture normal for this motor ?????
My tank has a capacity of 90 liter - means I`ll need 2 liters of oil per tank !!
Fuel consumtion was about 0.5l / km . My F100A on another boat takes about the same ...
Would appreciate to hear about the experience of other 90hp users !
Thanks in advance !

Jürgen

[boats.net]

It has a varable ratio oil pump, at idle uses about a 200:1 mix and 50:1 at full throttle.

[Searider]

Hi ,
Thanks for quick respond !
This is what confuses me - I could not go at all with WOT - but the oil consumption is even higher than going full time with full speed !
I wonder how much oil I will burn when I really go with WOT !

Cheers - Jürgen

[Searider]

short udate - Ichecked and adjusted the oil pump lever according w/shop manual and went yesterday out for a 210km long trip .
I burned exactly 100 liter of fuel and topped 1.6 liter oil to the tank .
This makes an ratio of 1:60 instead of 1:45 as it was before .

[rodbolt17]

your ratio is about dead nuggets.
much above about 3500 RPM its burning a 50-1 ratio.
means for every 50 L of fuel you should burn about 1 L of oil.
50 parts gasoline to 1 part oil.
50-1.

[Searider]

Hi Rodbolt & thanks for your comments !
Actually all I have done was to adjust the linkage to the oil pump according workshop manual . The setting before was the the stopper was reached long before the throttle was 100% open .
This resulted in tension respectively in deforming / stretching of the connection rod from the carbs to the oil pump when the the oil pump was at the stop already but I pushed the lever to maximum speed .
With extending the control lever by appr 4mm the setting now is that with full open throttle the lever of the oil pump is at the stop - but without force .
With this setting I went for a long trip and calculated afterwards a oil consumption of 1 part oil to 60 parts of petrol = 1 : 60 .
BTW - I used Putoline syntetic oil and do not think I did any damagage to the engine ..
The sea conditions did not allow me to go with more than 3500 - 4000 rpm .
Most of time I went with 3800 rpm .
What is your opinion ?

Cheers

[rodbolt17]

sounds about right to me.
however the ratio is gasoline to oil.
at WOT it will go as high as 50L gas to 1 L oil.

[Searider]

thanks mate - probably I confused everybody with telling the ration petrol / oil vice versa ..

Correct it should be like that :
This makes an ratio of 60 : 1 instead of 45 : 1 as it was before .

To be on the safe side I will make the oil discharge test according manual .
This year in the summer I intend to participate the Round Ireland Challenge with the Yamaha which will go over 1800km and I do not want to risk anything with the motor ..

[rodriesp]

Dear Searider,
Just saw this old thread you made about 90A oil consumption. I am from Argentina and I have got a 90AETO, I have never checked exactly the oil consumption as I use an internal gas tank and never measured exact consumption. But I observed that as the engina came from factory, the spark plugs were quite blacky an a little bit oily, not a lot, but sufficient to make me think why weren't they more coffeish or dry (also after putting a set of 3 new spark plugs). So I read the service manual and saw this adjustment. I adjusted the linkage and now the spark plugs came much better.
Just wanted to know if you are still using the engine and if you can give me a better idea about the normal oil consumption of this engine.

[pstephens46]

Been about three years since searider posted anything. Wouldn't expect a response.....