• Don't miss out on all the fun! Register on our forums to post and have added features! Membership levels include a FREE membership tier.

OIL RATIO DISCUSSION ON THE 800 CFI MOTORS

Thread Rating
5.00 star(s)

05900

Embrace the BRAAAAAAP!
Lifetime Membership
Nov 27, 2007
10,696
4,560
113
Where the Buffalo roam
Yes there is the paint on the lock nut, and I too considered the issue of the warranty. I decided more oil can't be a bad thing and I would rather have a healthy engine and take my chances with the warranty.

So adjust.clean paint with carb cleaner,repaint as needed right ? :face-icon-small-win
 
D

Daniel Boondocker

Well-known member
Dec 1, 2007
233
54
28
Idaho Falls
Nice thread.
Just to clarify mixing oil in the gas. I once burned down a modded engine dependent on tank mix by adding oil to the gas tank. The oil doesn't disperse by itself just by pouring it into the gas tank. It can pool and concentrate on the bottom of the tank. Then the top of the tank is low on oil concentration. Pouring fuel on top of the oil and shaking the sled isn't enough to disperse it. And some oil takes more agitation than others.
Mixing the oil in the gas is best done by measuring it into a gas can before the gas then shaking it well before you put it in the sled.
 
Last edited:
R

Rocketboy

Member
Nov 27, 2008
192
21
18
I will first say thanks to all of you for this post. I guess this is more of question than statement as I am not a big motor person.

I understand that the pre mix is not getting down to the crank. If that is the case we are not getting fuel down to the crank either to wash the oil off. If we are not washing it off could that be the reason that it needs a little less oil?

Now I understand the 32:1 idea and Ski Doo race school said 32:1 on the race sled a few years ago... Now there I can see that much oil as the gas was also getting to the crank if I understand it correctly and would be washing some of the oil off in turn needing more to keep it lubed.

Now- I may have just proved that I don't know much about motors so I am open to hear what I don't understand in what I put above.

That all being said- I have a 2011 155 that has 500 miles on it. Yes it had 500 on it when I got it..... correct- I have not even gotten to drive it yet. Don't know if I will before we head out west so I am not sure if I should turn the pump or not. I don't know what ratio I am at now and hate to be fouling out plugs on the side of the hill, but hate to have to pull it out of the hills as well!!

Thanks again for all of the info!!
 

mountainhorse

Well-known member
Lifetime Membership
Premium Member
Dec 12, 2005
18,606
11,814
113
West Coast
www.laketahoeconcours.com
I dont think that the gasoline diminishes the injection stream to any significant degree since it is shot directly at the lower rods thru the slots... and thru the bearings first.

I think that Kelsey or Curt could answer that one better than I.

Great Question Though!!!








.
 

richracer1

Well-known member
Lifetime Membership
Feb 2, 2011
3,626
2,480
113
Idaho Falls, ID
I will first say thanks to all of you for this post. I guess this is more of question than statement as I am not a big motor person.

I understand that the pre mix is not getting down to the crank. If that is the case we are not getting fuel down to the crank either to wash the oil off. If we are not washing it off could that be the reason that it needs a little less oil?

Now I understand the 32:1 idea and Ski Doo race school said 32:1 on the race sled a few years ago... Now there I can see that much oil as the gas was also getting to the crank if I understand it correctly and would be washing some of the oil off in turn needing more to keep it lubed.

Now- I may have just proved that I don't know much about motors so I am open to hear what I don't understand in what I put above.

That all being said- I have a 2011 155 that has 500 miles on it. Yes it had 500 on it when I got it..... correct- I have not even gotten to drive it yet. Don't know if I will before we head out west so I am not sure if I should turn the pump or not. I don't know what ratio I am at now and hate to be fouling out plugs on the side of the hill, but hate to have to pull it out of the hills as well!!

Thanks again for all of the info!!

Rocketboy, FWIW, I adjusted the pump on my 09 RMK and am around 40:1 now - the pump arm alignment arrow is just above the horizontal line on the pump body
- here's a link to my oil pump pic: http://www.snowestonline.com/forum/showpost.php?p=2775544&postcount=14

With that being said, I was also running a 40:1 pre-mix for breaking in my new SLP 777 BB kitted engine. I had zero problems with plug fouling, but I am using NGK irridium plugs. I'll continue adding about 1/2 to 3/4 of an ounce of oil for every gallon of fuel I put into the sled as added insurance.
 
R

Rocketboy

Member
Nov 27, 2008
192
21
18
I dont think that the gasoline diminishes the injection stream to any significant degree since it is shot directly at the lower rods thru the slots... and thru the bearings first.

I think that Kelsey or Curt could answer that one better than I.

Great Question Though!!!


.

I was talking on carbed motor compare to the CFI motor...... I think that fuel that was mixed as it got in the case would have some affect on washing or diluting the oil. (This is why I am not a motor guy!!!)
 

rockinmranch

Well-known member
Premium Member
Nov 29, 2007
873
744
93
There is some great onfo in this post. Thanks! We had another post going that started as overheating and evolved into oil consumption. I took some very accurate oil consumption checks on my rental sleds.
2012 600 rmk's (four checked) 1.8 oz, per gallon
2011 800 Pro Rmk 2.75 oz per gallon
2012 800 Standard RMK 2.25 oz per gallon

We have figured that the solution is to adjust the pump and/or add oil. Athough we know that the 800's don't consume much, the 600's are running at a critically low level. It may be a good service to anyone knowing people riding 2012 600's to make these 600 riders aware of the oiling issues.
 

rmk727

Well-known member
Lifetime Membership
Oct 3, 2008
568
154
43
71
SO.DAK
I'm not reading correctly or I just don't believe anyone saying that you are not helping the crank bearings by adding oil to the gas tank. The gas is sprayed directly onto the rod bearing that is in the crankcase then mixed in the case and forced up the transfer ports to the top of the piston, if this were not so the case would eventually fill with oil that is pumped on the bearings. The volume of the case and area of transfer ports is critical to the ability of the motor to make HP. Because of the gas being sprayed onto the rod bearing is exactually why summer storage is so important
 
O

Oregonsledder

Well-known member
Jan 27, 2009
992
815
93
Bend Oregon
I'm not reading correctly or I just don't believe anyone saying that you are not helping the crank bearings by adding oil to the gas tank. The gas is sprayed directly onto the rod bearing that is in the crankcase then mixed in the case and forced up the transfer ports to the top of the piston, if this were not so the case would eventually fill with oil that is pumped on the bearings. The volume of the case and area of transfer ports is critical to the ability of the motor to make HP. Because of the gas being sprayed onto the rod bearing is exactually why summer storage is so important

The issues is... without the auto oiling system, which has an oil line going to each end of the crank feeding oil directly to the PTO and Mag side crank bearings.... without the oiling system these end bearing will not get as much oil. Some oil... yes, as much...no.
 

pus1100

Active member
Lifetime Membership
Dec 25, 2007
236
43
28
50
Troms,Norway
I'm not reading correctly or I just don't believe anyone saying that you are not helping the crank bearings by adding oil to the gas tank. The gas is sprayed directly onto the rod bearing that is in the crankcase then mixed in the case and forced up the transfer ports to the top of the piston, if this were not so the case would eventually fill with oil that is pumped on the bearings. The volume of the case and area of transfer ports is critical to the ability of the motor to make HP. Because of the gas being sprayed onto the rod bearing is exactually why summer storage is so important

injectors are placed in the transfer port,not trottlebody injectors.similar to the 600SDI skidoo/rotax engine.no fuel goes via crankcase,only air and oil from oil injection pump.wonder why rotax scrapped the 800 SDI engine?
 

mountainhorse

Well-known member
Lifetime Membership
Premium Member
Dec 12, 2005
18,606
11,814
113
West Coast
www.laketahoeconcours.com
I'm not reading correctly or I just don't believe anyone saying that you are not helping the crank bearings by adding oil to the gas tank. The gas is sprayed directly onto the rod bearing that is in the crankcase then mixed in the case and forced up the transfer ports to the top of the piston, if this were not so the case would eventually fill with oil that is pumped on the bearings. The volume of the case and area of transfer ports is critical to the ability of the motor to make HP. Because of the gas being sprayed onto the rod bearing is exactually why summer storage is so important

NO GAS IN THE CRANK CASE on a 2011/12 motor...The injectors on a PRO motor fire UP into the transfer port.. NOT at all into the crankcase.

There are two oil nozzles (aka check valves..90 degree brass fittings in the case. That spray at the lower rod in the crankcase... the rod has an EDM slot cut into it. The nozzles spray "at" that slot when the crank comes around to 90 degrees BTDC or so. The oil does not pool in the case... too much air moving for that to happen. :face-icon-small-win

So NO... You are NOT helping the crank NOR the cylinder skirts by adding oil to the gas in the tank.


The oil is atomized by the oil nozzle (not the injector) as well atomized by the spinning bearings that it is coming out of (the PTO & MAG bearing) and pushed/drawn into the transfer/cylinder.








.
 
R

RKT

Well-known member
Jul 19, 2001
1,819
1,485
113
Preston, Idaho
www.2strokeheads.com
NO GAS IN THE CRANK CASE on a 2011/12 motor...The injectors on a PRO motor fire UP into the transfer port.. NOT at all into the crankcase.

There are two oil nozzles (aka check valves..90 degree brass fittings in the case. That spray at the lower rod in the crankcase... the rod has an EDM slot cut into it. The nozzles spray "at" that slot when the crank comes around to 90 degrees BTDC or so. The oil does not pool in the case... too much air moving for that to happen. :face-icon-small-win

So NO... You are NOT helping the crank NOR the cylinder skirts by adding oil to the gas in the tank.


The oil is atomized by the oil nozzle (not the injector) as well atomized by the spinning bearings that it is coming out of (the PTO & MAG bearing) and pushed/drawn into the transfer/cylinder.

.


Erik, are you sure about this? Is this info directly from Polaris?
 

Idahodoo

Well-known member
Lifetime Membership
Premium Member
Feb 7, 2008
321
160
43
Pocatello Idaho
www.jcscutomvents.com
I Checked my 2012 800 RMK and the scribe mark lined up below the center of the V notch, I adjusted 3 turns clockwise. Now the mark above center on the V.

I just had my sled in for a checkup (219 miles) & specificly asked them to check this, they said they did.

I will check how much oil she is using now, didn't really keep track, was adding oil in tank until I read all the oil pump adjustment threads everywhere.

I only took onf the hood & can to adjust & used a bore light & mirror to verify before after & only took about 30min and a beer to adjust.
 

rmk727

Well-known member
Lifetime Membership
Oct 3, 2008
568
154
43
71
SO.DAK
MH of course you are corret as always but I can't believe oil and air mix as well as oil and gas, plus then mix with gas, if you pull one apart where is the gas oil mix coming from thats in the case?
 

mountainhorse

Well-known member
Lifetime Membership
Premium Member
Dec 12, 2005
18,606
11,814
113
West Coast
www.laketahoeconcours.com
I'm definately on here to learn as well..

Sorry for the "short" reply above.... I'm wrong in my life about as much as I'm right.

My guess is this pooling of oil (I've seen it too) upon dissassemby is not representative of the engine in use at temperature with all the windage from the crank and rods and air being sucked thru the motor.... Also, the synthetics dont stick to the parts as well and I'm sure that after sitting, a lot of that oil that is coating parts settles into the bottom of the crank until the engine comes up to temp and speed again.

Kelsey, no.. this info is not coming from the factory...
So a question for a question... How would a fuel injector that is firing up the boost-transfer port, only at timed intervals, add any oil to the bottom end when the engine is running?


Kelsey, what is the clearance of the crank wheels and rod to the inside of the crank case?
Would that tight clearance create turbulence and "whip" that oil around in there?

Maybe I'm the one that is missing something???







.
 
Last edited:

mountainhorse

Well-known member
Lifetime Membership
Premium Member
Dec 12, 2005
18,606
11,814
113
West Coast
www.laketahoeconcours.com
The gas is sprayed directly onto the rod bearing that is in the crankcase then mixed in the case and forced up the transfer ports to the top of the piston,


This was the reason for my post earlier...

The injectors are located on the rear of the cylinder... above the throttle bodies in the boost-transfer port, not in the crankcase.

The injectors do not spray into the case, but at the inside wall of the rear (boost) transfer port.

The ECU "fires" this injector, it is my understanding, just as the transfer port opens to the cylinder intake stroke. The air being pushed/pulled into the cylinder takes this fuel with it... as well as the atomized oil that is moving thru the case.

That is my take on it.


picture.php
 
Last edited:

AKSNOWRIDER

Well-known member
Lifetime Membership
Dec 25, 2007
8,882
4,431
113
62
anchorage
Pretty sure you are right as well eric, at 8000 rpm the oil in the crankcase will look more like a rope wrapped around the crank though..as it crashes into the crank throws and the cases it breaks up gets atomized and pulled up the transfers as well as bounced off everything..which is what lubes the wristpins, skirts and even the bigend bearing..I promise at that rpm..no oil pump can spay hard enough to shoot across the case and coat the crank...on our big race motors we went thru great effort to isolate the oil off the reciprocating mass..it hurts power..back then dry sump oil systems were just being developed..we used big wet sump pans with all sorts of baffles, trapdoors and profiled scrapers that pulled the oil away from the rotating mass, as well as feathering crank throws, and eliminating as much as we could to make everything smoother to aid oil removal...... I think most people would be dumbfounded to see the turbulance in the bottomend of a motor..
 
Premium Features