[Salsman]

Hey there all.

I have an '02 Polaris 500 XC SP. I just replaced the throttle cable that broke, and now I have to adjust the Oil cable that is attached to it. There are 2 lines, one on the oil pump and one on the oil lever, do these lines have to line up when the throttle lever is closed when I do the inital install of the cable?

 

[avtech]

The two lines on the oil pump must align once all the slack is removed from the throttle cable (there must be a small amout of slack in the cable after you put it in). Squeeze the throttle until just before the carburetor linkage begins to rotate & check the pump settings at this time.

You may find it easier to take the carbs off to do the adjustment on the pump. Flatslides are nice that way. :wink:

 

[Salsman]

Thanks, I'll give that a try tomorrow morning. The Carb definately had to come off. lol. I was using almost a full resevoir of oil to a full tank of fuel. I did a little adjustment earlier, but was not quite sure. wit h the throttle closed, the lines we no where near lining up. They were about a quarter of a circle away from each other. Would that be the reason that I was not getting my top end out of the machine? It felt like it was bogginh out all the time.

 

[avtech]

What's the weather like up in "Frob"? It's been a few years since I've been up there. I got a kick out of watching the ships getting off-loaded at low-tide.

 

[Tallyman]

Oil should be calibrated so your engine is burning 50 to1. That is 1 litre of oil for every 50 litres of gas. When i bought my machine 600Rmk it was factory set at 100 to 1 so it was fortunate for me that I checked it!

 

[avtech]

I'm afraid that it's not all that simple, Tallyman.

Mikuni (or similar) oil injection systems are variable. They can be as low as 100:1 at idle (as to not foul the plugs) to as much as 20:1 at full throttle. This is very dependent on what type and size of carburetors are used. If you look at the fuel flow curves for a mikuni VM carb, you'll notice that it's not linear. For the most-part, there is progressively more oil delivered (by ratio) as the throttle is pulled. Arctic Cat gives oil consumpsion tables ( in cc's per 2 min period with the oil lever fully actuated) in their manuals. This is mostly to confirm, or perhaps troubleshoot a faulty system. Pump synchronization has always been by means of aligning rigging marks, not by trying to achieve an "ultimate" fuel /oil ratio.

Luckily, you've adjusted your oil system to the fat side. I can't see how the Manufacturer's technical information can been wrong after so many years.

Stick to OEM specs unless you REALLY know what you're doing.

 

[Tallyman]

I'm afraid that it's not all that simple, Tallyman.

Mikuni (or similar) oil injection systems are variable. They can be as low as 100:1 at idle (as to not foul the plugs) to as much as 20:1 at full throttle. This is very dependent on what type and size of carburetors are used. If you look at the fuel flow curves for a mikuni VM carb, you'll notice that it's not linear. For the most-part, there is progressively more oil delivered (by ratio) as the throttle is pulled. Arctic Cat gives oil consumpsion tables ( in cc's per 2 min period with the oil lever fully actuated) in their manuals. This is mostly to confirm, or perhaps troubleshoot a faulty system. Pump synchronization has always been by means of aligning rigging marks, not by trying to achieve an "ultimate" fuel /oil ratio.

Luckily, you've adjusted your oil system to the fat side. I can't see how the Manufacturer's technical information can been wrong after so many years.

Stick to OEM specs unless you REALLY know what you're doing.[/b]

 

[Tallyman]

Hey Avtech I cant disagree with anything you have said, however at the end of a day having burned 50 litres of gas at mostly 7000 to 8000 rpm I want to see that a litre of oil was burned! If too much oil is used, the octane rating will be reduced, which could cause engine overheating and meltdown. I doubt that the factory calibrates each individual engine, at least thats what my dealer said. Anything to add?

 

[avtech]

Tallyman,

I can see what your dealer is trying to tell you, but there's more to fuel / oil mix than there was in the old days. An actual ratio doesn't mean all that much anymore, at least not enough to be worried about it.

When the engineers at Polaris USA designed the engine that's in your sled, they had specific design requirements for the oil injection system for that PARTICULAR engine. Amung them were 1) mechanical lubricating qualities and quantities needed to adequately lubricate the intenal components. (Don't forget that there may be some oil pumped directly to some bearings, or other critical components of the engine, which is later mixed with the incomming fuel charge in the case) 2) emissions 3) reliability (plug fouling, exhaust valve deposits, etc.) 4) driveabililty / performance. (The stoichiometric ratio for gasoline is 14.7:1) Adding an excess amount of oil at any given throttle may bog down your engine, or otherwise alter this ratio.

Once they determined what they needed, they used a pump that would give them exactly what they needed... plus some, as a fudge factor. These pumps are very precise metering devices, but they need a reference point, which is the rigging marks on the pump housing and lever. Align those marks, and the pump does the rest.

For example: A 2000 Arctic Cat ZR500EFI requires that at 3000 RPM and the pump arm fully actuated, that there be 11.275 to 14.122 cc's of oil pumped into the engine. Yet a 600EFI engine only requires 9.224 to 11.558 cc's. ??? Does this all make sense? Not really, because you'd expect that the 600 engine need more oil, as your burining more fuel, and making more power. The people at Suzuki somehow figured that out. Each engine is different.

I don't want to go on about this subject, other than to say that unless the manufacturer , not the dealer, tells us otherwise, either by information contained in the factory service manuals, or additional technical information contained in service bulletins, etc, we should have no reason to doubt them. I don't claim to know more about this than the design engineers, so I believe what they're telling me. It hasn't let me down yet.

Your initial set-up of 100:1 does seem off by quite a bit. That means, that you processed 100 litres (26.42 us gals.) of fuel through your sled before having to add one litre (1.06 us quart). Was the pump rigging off? What else did your dealer say?

 

[michahicks]

This really shouldn't be all that complicated. I agree that the alignment marks are a good place to start. Also not going to disagree with avtech's process of setting them. But as Tallyman mentions, at the end of the day, somebody curious about their oil consumption SHOULD see something like 50:1 .......on average (as observed after several tankfulls). I have personaly observed averages anywhere from 40:1 to 70:1 on my own sleds (mostly Polaris) over the last 35 years, have never had an oil related failure of any kind. If you feel like you want/need to burn a little more or a little less, then of course you are on your own from an engineering standpoint - but this is where you would make your adjustment.

By the way, many of those pumps have a second mark on the lever - one that is supposed to line up at WOT. Have never yet seen a set up when both marks line up when they are supposed to (first mark at idle/second at WOT).

 

[Salsman]

ok now, it's all set up and all I need to d ois burn out the excess oil in the engine that is clogging it up. Had to literally drain out my power valves, lol. they were full up. I noticed that there is a second mark on the lever, it is more like a dot than a line. I adjusted the oil lines so that they match up when the engine is at idle. I'll have to wait and see what the consumption is now and go from there. Thats when the weather finally warms back up, and we get some snow. there hasn't been too much snow here this year. and the temperature has been pretty cold. What snow we did get this season so far, it has almost been all scrubbed away from the last blizzard. Other than that, it's been pick and choose between the rocks to find a path for the snowmobile.

 

[Salsman]

(first mark at idle/second at WOT).

What is WOT?. Wide open Throttle?. .lol

 

[Tallyman]

ok now, it's all set up and all I need to d ois burn out the excess oil in the engine that is clogging it up. Had to literally drain out my power valves, lol. they were full up. I noticed that there is a second mark on the lever, it is more like a dot than a line. I adjusted the oil lines so that they match up when the engine is at idle. I'll have to wait and see what the consumption is now and go from there. Thats when the weather finally warms back up, and we get some snow. there hasn't been too much snow here this year. and the temperature has been pretty cold. What snow we did get this season so far, it has almost been all scrubbed away from the last blizzard. Other than that, it's been pick and choose between the rocks to find a path for the snowmobile.[/b]

 

[michahicks]

<<<Wide open Throttle? >>>

Yessir....

Snow hasn't been much better here in the midwest. Where I like to play has seen mostly very dry, powdery, lake effect snow that doesn't pack well at all. Getting a decent base on the trails just hasn't happened.