Oil pump adjustment.... revisited

Oregonsledder · Aug 18, 2012

The oil pump adjustment topic has been one of the hotter ones over the last year. I for one have until now, subscribed to the turn up the pump 3 turns (believing that it would increase the flow rate over the entire throttle range). Recently, there has been a post or two saying that adjusting the pump set screw only changes the flow rate at idle and nothing else. There was no explanation as to why it only changed the idle oil flow rate so I thought I would try to think about that as a possibility and try to understand and then explain it.

Here goes. On most other older sleds, you adjust the oil pump by adjusting the cable that splits off from the throttle cable. There is no set screw, just a cable adjustment to align the point on the oil pump arm and the oil pump body scribe mark. The cable will have two jam nuts that allow for this lengthening or shorting of the cable to align the marks.

On the PRO, the adjustment set screw just determines where the oil pump arm pointer and pump body scribe align. The only way to increase oil flow over the range of the arm swing, would be to shorten the cable thus, effecting the end (wide open/max flow) rate as well. Think of it this way... on older Mikuni rack carbs you adjust the idle (where the slide rests) by adjusting the idle slide stop screw. You adjust the wide open position of the slide with the cable adjuster. This is the same principle at play. Unless there is a way to shorten the oil pump cable you cannot change the oil flow rate and mid range or wide open throttle. Another difference in the PRO pump operation, is that in older sleds the pump arm spring would force the pump to max flow rate if the cable was to break, I have seen a few in my shop with a broken cable and they usually immediately foul the plugs and stall, or at least burn an excess of oil. On the PRO the spring forces the oil pump arm towards minimum flow and that’s why there is a set screw to set the min or idle flow rate.... in other words, a pump arm stop.

Additional proof for my hypothesis is, in the service manual for the PRO it explains how to prime the oil pump to remove any air from the oil lines. You are to use a wire/coat hanger and pull the pump arm all the way up (max flow) while the engine is at idle. So my conclusion is that the pump output is mostly determined by arm position relative to the pump body and less effected by engine rpm. If you want more oil over the entire throttle range, you have to be able to adjust the cable.

I will still add oil, 1 ounce per gallon just to be sure I’m getting adequate engine oiling.

I hope this helps a little and doesn't confuse more than it helps.

I also welcome any one who can prove that adjusting the pump set screw has any affect on oil pump flow rate off idle. Saying that oil tank usage increased after adjusting the set screw won’t convince me, I adjusted mine 3 turns and didn’t see any change in usage.

Matte Murder · Aug 18, 2012

So are you going to adjust your cable? Are you sure adjusting your cable will actually increase oil flow? My 12 used exactly 1 gallon of oil for 500 miles. Half or less than the Ski Doos I rode on the same day/times.

Oregonsledder · Aug 18, 2012

Matte Murder said:
So are you going to adjust your cable? Are you sure adjusting your cable will actually increase oil flow? My 12 used exactly 1 gallon of oil for 500 miles. Half or less than the Ski Doos I rode on the same day/times.

I have not yet figured out a way to adjust the cable/rod, there isn't any adjuster on the rod/cable that I know of. I suspect the EPA has encouraged Polaris to make the oil systems work this way so it isn't easy to adjust the oil flow. Guys who are saying that they have seen an increase in oil consumption after adjusting the oil pump set screw are seeing more consumption due to snow conditions.... I suspect. You will use more oil per mile in the deep than on firm snow, so watching the oil tank level and then the odometer is not very exact.

AKSNOWRIDER · Aug 18, 2012

Uhmm...oregon, the oil pump arm/linkage..is hooked to the throttle shafts thru the screw adjuster..when you adjust that..it does change the oil pump travel..in other words you are changing the oil pump arm position relative to the throttle shafts, and when you move the shafts it moves the arm..thus varying the amount of oil the motor gets...
5.If adjustment is required, locate the oil pump linkage adjuster on the throttle body. Open and release the throttle several times to verify throttle plates are closed.
6.Loosen the adjuster jam nut. Using an Allen wrench, turn the adjuster screw clockwise to raise the oil pump lever arm. Turn the screw counter-clockwise to lower the oil pump lever arm.
7.Visually inspect the lever notch/scribe mark alignment. When in alignment, tighten the jam nut without moving the adjuster screw.
Oil Pump Adjustment Settings
PART NUMBER
ARM MARKING
LEVER SETTING
25210001204439
600B Linkage Adjustment
Set lever notch in-line with oil pump scribe mark.
12043631204438
800BLinkage Adjustment
CAUTION
Failure to properly set the oil pump lever arm may cause severe engine damage.
LINK
AGE ARMOIL SUPPLYLEVER NOTCHSCRIBE MARK
CAUTION
The oil pump lever and pump boss marks must be observed straight-on to yield accurate results.
LOOK THROUGH THIS OPENING
J
AM NUTADJUSTER SCREW

Oregonsledder · Aug 18, 2012

AK i will take your word for it, as I have yet to have a PRO engine on my bench where I can get a real good look at the pump. From what I can see with the can removed using a mirror and flashlight, and the shop manual which you quote above.... I can't see how adjusting the set screw can effect the entire range. I guess Carl's and some others and I just don't get it?? LOL

AKSNOWRIDER · Aug 18, 2012

take and get it where you can look at it..when you move the throttle..its moving your adjuster as well..thus moving the pump arm..so any change in the adjuster moves the arm..both at idle and at throttle....easy way to see it...pull the seat and the tank bolts..loosen the shroud and slide the tank back..then pop the airbox and you can see it pretty good...

Oregonsledder · Aug 18, 2012

AKSNOWRIDER said:
take and get it where you can look at it..when you move the throttle..its moving your adjuster as well..thus moving the pump arm..so any change in the adjuster moves the arm..both at idle and at throttle....easy way to see it...pull the seat and the tank bolts..loosen the shroud and slide the tank back..then pop the airbox and you can see it pretty good...

The easy way???? LOL

gman086 · Aug 18, 2012

At a certain point the lever arm opens the oil flow fully yet can continue past that point the same as carb slides are wide open while you can still adjust the slides higher with zero effect on WOT. I posted about this originally and will stand by my statement that turning up the oil screw is just wasting oil at the lower rpm range and that you NEED to add more oil to the tank.

Have FUN!

G MAN

Oregonsledder · Aug 18, 2012

There seems to be as many opinions as posters, but one thing is for sure.... if you add oil to the tank it will be burnt. I will dig deeper into this issue but for now I still can’t see how adjusting the adjuster set screw can add oil at any point other than at idle.

Stewy · Aug 18, 2012

Oregonsledder said:
The oil pump adjustment topic has been one of the hotter ones over the last year. I for one have until now, subscribed to the turn up the pump 3 turns (believing that it would increase the flow rate over the entire throttle range). Recently, there has been a post or two saying that adjusting the pump set screw only changes the flow rate at idle and nothing else. There was no explanation as to why it only changed the idle oil flow rate so I thought I would try to think about that as a possibility and try to understand and then explain it.

Here goes. On most other older sleds, you adjust the oil pump by adjusting the cable that splits off from the throttle cable. There is no set screw, just a cable adjustment to align the point on the oil pump arm and the oil pump body scribe mark. The cable will have two jam nuts that allow for this lengthening or shorting of the cable to align the marks.

On the PRO, the adjustment set screw just determines where the oil pump arm pointer and pump body scribe align. The only way to increase oil flow over the range of the arm swing, would be to shorten the cable thus, effecting the end (wide open/max flow) rate as well. Think of it this way... on older Mikuni rack carbs you adjust the idle (where the slide rests) by adjusting the idle slide stop screw. You adjust the wide open position of the slide with the cable adjuster. This is the same principle at play. Unless there is a way to shorten the oil pump cable you cannot change the oil flow rate and mid range or wide open throttle. Another difference in the PRO pump operation, is that in older sleds the pump arm spring would force the pump to max flow rate if the cable was to break, I have seen a few in my shop with a broken cable and they usually immediately foul the plugs and stall, or at least burn an excess of oil. On the PRO the spring forces the oil pump arm towards minimum flow and that’s why there is a set screw to set the min or idle flow rate.... in other words, a pump arm stop.

Additional proof for my hypothesis is, in the service manual for the PRO it explains how to prime the oil pump to remove any air from the oil lines. You are to use a wire/coat hanger and pull the pump arm all the way up (max flow) while the engine is at idle. So my conclusion is that the pump output is mostly determined by arm position relative to the pump body and less effected by engine rpm. If you want more oil over the entire throttle range, you have to be able to adjust the cable.

I will still add oil, 1 ounce per gallon just to be sure I’m getting adequate engine oiling.

I hope this helps a little and doesn't confuse more than it helps.

I also welcome any one who can prove that adjusting the pump set screw has any affect on oil pump flow rate off idle. Saying that oil tank usage increased after adjusting the set screw won’t convince me, I adjusted mine 3 turns and didn’t see any change in usage.

Your right. This is exactely how my long time polaris dealer explained it to me as well.

die hard poo · Aug 19, 2012

The oil pump linkage arm serves the same exact purpose as the cable did on the older cfi-4 motors, to control the oil pump injection ratio. To adjust the oil injection ratio to throttle body input: you MUST tighten the cable tighter than what the throttle cable is; therefore changing the oil injection ratio(on older cfi-4 motors).

On the Pro cfi-2 motors, the linkage is adjusted (or tightened) by the set screw, it is NOT LIKE A IDLE ADJUSTMENT SCREW!!!! An idle adjustment screw is a throttle STOP, not a tensioner.
Here is a picture of the back side (fuel tank/airbox removed) of the oil pump linkage adjustment. It is a cantilever operation, the more you screw in the adjustment screw, the more it pulls up on the linkage arm; therefore INCREASING the oil injection ratio per throttle input.

I have adjusted both my 11 and 12 Pro's oil pump injection ratio and successfully INCREASED my oil consumption significantly. I use approximately 1/2 of the sleds oil tank per full tank of fuel. I am riding primarily back country mountain riding. I have ran the same spark plugs on both sleds each with approx. 1000-1300 miles and my exhaust valves were in great operation. I use Amsoil interceptor oil BTW.

I personally feel that adjusting the oil pump and allowing the sled to reach full operating temperature prior to operation has increased the reliability and longevity of my motors (both of which have yet to let me down).

I just opened up my 12 motor to verify my internals were in good shape prior to installing a turbo kit for this season(first turbo kit). I found my crank bearings to be in great condition and my cylinder skirts showing NO signs of cracks. Same with the pistons. I did have the typical light scuff on the intake side of the MAG piston from piston skirt drag, but I am confident it would of ran great for many miles more(it had about 1300 miles on it). The reason I did all this was merely preventative maintenance prior to installing the turbo kit, which is my first one and I want ensure she will be as reliable as possible. Anyways here is a couple pics of my summer project.

67413FD8-580B-43BE-A4B3-F5E3268D57D7-12477-000014E19D290B97.jpg

2CCC538A-68DA-4415-B861-52A2DAEE265C-12477-000014E1A800A078.jpg

A501B8B7-EF98-4D38-AFC7-38DF2E3010E7-12477-000014E325579B69.jpg

rocket · Aug 19, 2012

Oregonsledder said:
There seems to be as many opinions as posters, but one thing is for sure.... if you add oil to the tank it will be burnt. I will dig deeper into this issue but for now I still can’t see how adjusting the adjuster set screw can add oil at any point other than at idle.

If you are not experiencing any significant change in oil usage when making adjustments, that may be possible, especially if you don't spend much time in the low to midrange RPM. At idle, the motor uses so little oil that even a drastic pump adjustment won't make any signficant difference in consumption. At some point in the midrange to upper RPM, the pump "maxes out" and won't pump any more oil when the pump arm is opened further, so a pump adjustment won't have any effect beyond that point either. If you spend most of your time at either end of that spectrum, adjusting the pump may not make much difference to your sled, but the same won't be generally true for everyone. The other thing I'll bring up again is oiling the crank. While you are correct that mixing oil into your fuel does put extra oil into the cylinders, the only thing that puts oil into the crank is the oil pump, because there are no oil "drip feed" holes into the bearings on the CFI motors. Even a little bit of extra oil going into the crank bearings is going to be a good thing.

Reg2view · Aug 19, 2012

die hard poo is right about the linkage - when the linkage screw is advanced, it advances the pump position through the entire range of movement for the lever arm. It is not an 'idle screw' adjustment, with just the starting position advanced. At least not on mine, and I did adjust mine myself, and looked it over carefully. Have the manuals, too.

With respect to flow rate - we just don't know at what point in the lever range of motion that max flow occurs, as rocket clearly states and as GMan infers. It could be that advancing the lever adds little oil up top. Someone could test, but applying it to all sleds would be arbitrary, since the only indexing is done at idle, and it's not precise. Nothing wrong with adding oil in the gas, as long as you're not fouling plugs, clogging injectors, running lean. Do what you feel you need to do.

geo · Aug 19, 2012

The oil pump will have a max opening (hole doesn't get any bigger) but where that is, is being debated here. It could be at that rather large max mark area it could be above or below it. The little things are pretty crude if you pull one apart.
RPM has a greater effect as to how much oil flows at wide open than the exact location of the arm (to a point). 8250 will flow alot more than 7950.
If you are set to clutch at 7950 (that's where I will start and work from there) you will need to set the pump to oversupply at low throttle positions if you want extra on the top.
I like to see a big puddle of oil in my crankcase and the bearings dripping if I take my topend off. The EPA doesn't but it's not their sled.
Bearings love to bathe in oil so I like them to be happy and enjoy the ride. That puddle in there is your extra oil at wide open.
It takes a long time for the air flow to pick up all the excess and send it to the combustion chamber. Longer than most think. The pull many mountain riders consider long really is just about enough time for the oil to get used up (all the time more is coming in to). Then you shut down and side hill or go back down and star to fill up the happy puddle again.

Oil in the tank is helpfull too. Not all the oil in your premix will go straight to the combustion chamber and out the exhaust. Some will hit the piston or the port walls and dribble down. How much oil in your fuel will dictate on how much precipitates.

I will do both (pump and premix) and keep track of total oil use (pump and premix) and shoot for a 32 to 1 ratio (my Cat's until 2012 came from the factory set this way, do they know something?). But, I will try to supply the majority of it through the bottom end like the good ol' days lol. 2 strkts were designed to be lubed this way and only EPA requirements forced the engineers to try and re-invent it.
IMO if you foul plugs from too much oil you need to change the heat range for your style of riding. If you feel a burble or running problems from turning the pump up you have a just uncovered another issue from clutching or engine management. We used to burn 10W oil at 20 to 1 in old inefficient 2strokes and still be able to set up for clean running.

Be nice to your 2strk. Pour in the oil. Just wash your riding gear more or join the 4strk revolution lol.

Oregonsledder · Aug 19, 2012

geo said:
The oil pump will have a max opening (hole doesn't get any bigger) but where that is, is being debated here. It could be at that rather large max mark area it could be above or below it. The little things are pretty crude if you pull one apart.
RPM has a greater effect as to how much oil flows at wide open than the exact location of the arm (to a point). 8250 will flow alot more than 7950.
If you are set to clutch at 7950 (that's where I will start and work from there) you will need to set the pump to oversupply at low throttle positions if you want extra on the top.
I like to see a big puddle of oil in my crankcase and the bearings dripping if I take my topend off. The EPA doesn't but it's not their sled.
Bearings love to bathe in oil so I like them to be happy and enjoy the ride. That puddle in there is your extra oil at wide open.
It takes a long time for the air flow to pick up all the excess and send it to the combustion chamber. Longer than most think. The pull many mountain riders consider long really is just about enough time for the oil to get used up (all the time more is coming in to). Then you shut down and side hill or go back down and star to fill up the happy puddle again.

Oil in the tank is helpfull too. Not all the oil in your premix will go straight to the combustion chamber and out the exhaust. Some will hit the piston or the port walls and dribble down. How much oil in your fuel will dictate on how much precipitates.

I will do both (pump and premix) and keep track of total oil use (pump and premix) and shoot for a 32 to 1 ratio (my Cat's until 2012 came from the factory set this way, do they know something?). But, I will try to supply the majority of it through the bottom end like the good ol' days lol. 2 strkts were designed to be lubed this way and only EPA requirements forced the engineers to try and re-invent it.
IMO if you foul plugs from too much oil you need to change the heat range for your style of riding. If you feel a burble or running problems from turning the pump up you have a just uncovered another issue from clutching or engine management. We used to burn 10W oil at 20 to 1 in old inefficient 2strokes and still be able to set up for clean running.

Be nice to your 2strk. Pour in the oil. Just wash your riding gear more or join the 4strk revolution lol.

I agree with your take on this. The pump distribution of oil is clearly not really understood. 2 stroke engines need oil plain and simple, both on top and around the pistons but also on the crank and rod bearings. They have always smoked and most likely will always need to smoke to be healthy.
I have my pump turned up 3 turns and I add 1 ounce per gallon to the tank and my plugs still look like they came out of a 4 stroke. I suspect I could add even more oil to the tank before I would see a loss of performance or plug fouling.

I am going to find a way to get a pump on my bench and find a real way to measure output, and what effects it, at least on the bench. I have always felt that snow conditions and riding style has a significant impact on oil per mile usage.

I wouldn’t be as concerned about this issue if I felt the combined fuel and oil ratios from the factory were even close to being rich enough for long engine reliability.

Reg2view · Aug 19, 2012

Look at it this way - on my e-tec doo, there is no oil pump adjustment.

+1 Poo.

mountainhorse · Aug 20, 2012

Great presentation and discussion...

The pump is a simple variable displacement style unit.... the lever arm position controls the the output relative to throttle position. As the arm is moved, the orifice that the oil moves though out of the pump is increased in size.

RPM also affects the amount of oil output... but I'm told not as much as varying the arm position.

If you change the position of the arm relative to to the throttle position you will change the oil delivered to the engine throughout the throttle-postion range. If the arm STARTS at a position that relates to a lager variable orifice inside the pump... then the orifice is larger relative all other throttle positions.

The oil pump on the PRO can/will deliver more oil to the engine if the arm is moved beyond the factory set position. The factory setting does not "max out" the pump... It is possible to turn up the delivery of oil on the engine (or decrease it for that matter).

The oil pump design really has not changed much in recent years..The linkage has mad it possible to have a lighter throttle spring... but operation has really not changed.

If you advance the arm position of the oil pump with the throttle plates in the Idle position...More oil will be delivered at idle and ALL throttle positions beyond idle.

Another topic has been oil pooling in the crankcase and more smoking at startup than many are used to.

In the new engines with no fuel flowing through the crankase... and the less tenacious nature of the new synthetic oils (the oil does not stick to the parts as well as older mineral oils) this pool of oil is not washed out as fast as engines with atomized fuel flowing through the crankcase. Simply put, the oil that HAS "pooled" does not clear out as fast. I Have noticed on the turbos with aux injectors in the TB-boots that this is minimized...as well as those people using high quality mineral oils. Once the engine warms up... and the pooled oil has been moved through the engine or coating the internals... the smoking goes away.

IMO... turning up the AMOUNT of oil delivered to the engine, in a reasonable fashion, can only HELP and never hurt the engine or the performance of the engine.

My 2 cents.

mountainhorse · Aug 20, 2012

An extreme example of arm position and the pumps ability to move some serious oil.... EricW on the forums here had his Dragon (same pump... different control .. cable vs linkage-rod)... His pump was improperly set by the turbo installer where the pump arm was WAY advanced... he emptied his oil tank in less than one fuel tank and needed to drain some out of another sled to get the sled back to "camp" where we adjusted it properly.

These pumps CAN move some serious oil...In the case of the PRO RMK... This is limited by the range of adjustments that the factory linkage allows...ie, with the design of the linkage you cant really "crank up" the oil delivery a HUGE amount.... that might require a modded or custom linkage

If you really wanted to test this... wire the oil pump in the fully open position and see how fast the oil tank is emptied... IMO... that would be in less than one tank of gas.

pura vida · Aug 20, 2012

sorry to say oragon but your assumptions are wrong. i broke/bent my oil rod and it kept coming off throughout a ride (long boring story). i got tired of trying to put it back on every few minutes so i just left it off and like MH experienced i burnt a HUGE amount of oil. so much so that by the end of the day i was actually starting to have runability issues and was low on oil long before i was low on fuel. i adjusted my pump setting and and did notice a calculated overall increase (or is it a decrease...), over multiple rides, in the oil ratio.

rather than debating approximately how much oil you are using and then arguing over if it is due to the change in oil adjustment or riding conditions why not just check your oil ratio after a ride? yes the pump is progressive and snow conditions have a huge effect on oil usage but you can still easily figure out your overall ratio after any ride. for me, i turned my pump up b/c i was not happy with an overall 45-50:1 ratio on an average ride. so now, on my 11 my oil consumption is between 35-40:1 on heavy throttle days and at the worst, 50-55:1 on easier trail days. it could still handle another turn or two to get that number closer to the "magic" 32:1 but it wasn't that far off so i didn't worry about it that much. the one thing i'm still not convinced on and haven't done yet is adding extra oil to the tank. i don't think it hurts anything but i'm not convinced it is providing any real advantage either. don't know though...

pv

ENDO1 · Aug 20, 2012

OK this is starting to get a bit confusing, in die hard poo, pic, their are two adjusting screws, one with a lock nut and one with a spring, which one are we talking about ? (from earlier post thought it was the one with the lock nut) Won't the one the spring affect the tps setting, I thought the one with the lock nut was the only one to change the oil and you can get to it from the front, I don't have my sled in front of me to look at right now. Their have been some good people that have replied about this, some of them I have got some good info from in the past, but it seems to be split as to how much this really needs to be done, it sounds like that if you are an aggressive rider you don't need to worry about it to much, but if you do a lot of trail riding at lower speeds all day then maybe it's a good idea.

Oil pump adjustment.... revisited

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Similar threads