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Discussion Starter #1
Ok guys, The engine rebuilt is done and I will probably start it Friday... The little thing I'm wondering now is that I change all the oil pump hoses.I clean the oil tank and change the tubes connecting the oil tank to the oil pump. New filter. Now everything is dry, no oil at all. When I will start the engine, did I have to let the kill switch to off position and the gas valve closed, pulling the cord as long as I saw oil coming in the cylinder while putting the throttle at WOT? It is seem correct to you or I worried too much? I mean, it should be a trick to bleed the system! Thanks
 

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NO, you are absolutely correct. You should be running a tankful of 40:1 or 50:1 for initial break-in, then go to regular gas. The 40:1 or so plus all the lube you put on everything when you put it together should be enough to lube it properly until the oil gets to the engine by running it.

Bryan
 

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Discussion Starter #3
ok, already heard about the pre-mix gas when break-in. But don't seem to be all people's opinion. I remember readin on the site that putin pre-mix gas when break in can makes some issues. Don't remember what was talk about but I'm sure I read something about it!
 

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I think one of the issues is not to use Synthetic as its lube qualities are so high that rings do not seat.

I've pre-mixed all my engines after rebuild during break in. And I've never fouled a plug from it.

Wait for one of the 'gurus' to answer.

Bryan
 

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To premix on break-in or not... 6 of one half dozen of the other... personally I never use premix I leave it to the injection system, as long as your pump and lines are properly bled you should have no problem. Premixing can actually lean out the fuel ratio when being run in an engine jetted for oil injection.
 

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My 700 went exactly 4.5 miles on a NEW engine when the oil cable failed, giving no oil. I had everything bled correctly, felt I didn't have to premix that first tank. Two new pistons and a cylinder later (on a NEW engine) taught me to premix. Two plugs are a LOT less expensive than two pistons, trust me!!

There is also a bleed screw on most pumps, unscrew the screw until no more air comes out; that will help tons in the number of pulls. I also pull the plugs and put a bit of oil down the holes to ensure I have some oil in there when pulling; last time I did this, it took over 75 cranks of the rope before oil appeared at the carbs. You don't want that many revolutions on your rings with no lube. It's MUCH easier to pull over without the plugs in as well ;)
 

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that and also wire the oil lever to full till it bleeds
 

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Discussion Starter #9
Really, I never saw those bleeding screw. I will check better... Thanks guys, think 75 pull of cord is too much for the weak muscles![:0][:D].
 

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Originally posted by BC_Dan
[br]My 700 went exactly 4.5 miles on a NEW engine when the oil cable failed, giving no oil. I had everything bled correctly, felt I didn't have to premix that first tank. Two new pistons and a cylinder later (on a NEW engine) taught me to premix. Two plugs are a LOT less expensive than two pistons, trust me!!
So Dan, your telling me that the only way for the cable to fail is to have a new engine? What happened to you could have happened at any time and in no way relates to break-in with or without premix, the only thing it relates to is bad luck when a cable fails. If your system is bled and operating correctly you will have no trouble with break in using the oil injection system. Premix if you want to, personally I dont.
 

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had i had premix in that first tank, I would have easily discovered there had been NO oil used from that first tank, and located the problem and repaired it before the second tank, i would not have had to replace two pistons and a cylinder. I caused the problem when I installed the pipes, cables don't usually fail.
 

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I don't feel it is necessary to pre-mix the oil. You should however make sure that your pump is bled. Most if not all Mikuni oil pumps on Polaris motors have an oil bleed screw. Just loosen the screw until you see no signs of air. That later is what a Polaris manual would recommend, but I would also bleed the system by turning the motor over as some guys have described above. I take the carbs off and make sure the pump is at full capacity to speed up the process. Pull until you see plenty of oil coming out in the boots and make sure you can see no air in the lines. This is especially important on a new motor because there is no oil in the motor. Do not forget to double check your pump adjustment as well. I would suggest using an assembly lube when you assemble a motor. If you use a light lube or motor oil when you assemble a motor, the oil does have a chance to run off of the parts during the time that it sets before you start it. Using a thicker assembly lube, or a spray assembly lube when you assemble a motor, makes sure that you have lubrication until the engine starts. This is where priming the system is important as well. Priming reduces the time that it takes for the oil to get to the motor, no to mention that a pump will not pump oil if there is air trapped in the PUMP. This trapped air may not work out over time either, so you should not depend on the pump to bleed itself after the engine is started. Hope this helps ya out a little.
 

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Discussion Starter #13
I try to bleed it today, as you guys stated there was a bleeding screw on the top of the pump. But I pull the cord 20 minutes, and still no oil in the middled tube. Both PTO and MAG cylinder was at 1\2 of the entire length. Do you think a pump can failed only on 1 outlet?
 

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It could be the pump, but it may also be the check valve on that cylinder. I have attached a couple pages from my manual that describes how to check the check valves. They tell you to run the motor, but pulling it over may work as well. Notice, if you do run the motor they tell you to use a 40:1 mix in the tank for obvious reasons lol. The valve should open between 2 and 5 psi. Basically, if oil flows with the valve off the line and does not flow with the valve on the line, then the problem is the valve. The valve may be your problem, check it out and see.

[attachment=58923]

[attachment=58924]
 

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Discussion Starter #15
Thanks sinjin588, My manual don't talk about this method and the end play of the drive gear for the oil pump. I check hard in the manual but they said to put back the shims that was already here! And they never talk about the check valves. Can you post other pics of the end play like what it should be. If I have more issues I will take it apart and measure the shim thickness!
 

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Originally posted by STEVE650
[br]Thanks sinjin588, My manual don't talk about this method and the end play of the drive gear for the oil pump. I check hard in the manual but they said to put back the shims that was already here! And they never talk about the check valves. Can you post other pics of the end play like what it should be. If I have more issues I will take it apart and measure the shim thickness!
Yea, if you put the shims back that came out, and you did not change anything else, it should be alright. If you replace parts or do anything else that can change clearances, then you need to check the end play. Your problem sounds like a check valve to me, since you said that the other two carbs were getting oil. I did not include the entire section on end play adjustment so here is the rest for ya. What kind of manual do you have, and what year is you motor? These pages are from a '96-'98 Polaris Service Manual, for your own reference.

[attachment=58957]
 

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Discussion Starter #17
Its a 650 carb version. Of course my manual stop to 1994, and this is probably why I don't have the section you have! Thanks a lot for the spec. I change the crankcase and put my old oil pump. I will re-check the end play as describe![;)]
 
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