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Oil Metering Pump Removal Reliability question

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Old Dec 13, 2005 | 12:52 AM
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Oil Metering Pump Removal Reliability question

Just wanted to know if the rotary was more reliable if you removed the OMP and premixed your fuel or just left the OMP on? Seems like an awful lot of work to premix EVERY tank of fuel just to have one piece off of the engine.
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Old Dec 13, 2005 | 12:59 AM
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some people do both,leave the OMP on and premix..you definitely don't have to worry about lube if you do both..but for every action they say is a reaction..so if you take off the OMP it needs the lube through the premix..or else,,flap,flap.flap..you know what i mean..hope that is along the lines of what you were after..
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Old Dec 13, 2005 | 01:11 AM
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Just tryin to figure out which one is more reliable, with or without? I know opinions will vary, but cant hurt to hear both sides of the issue.
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Old Dec 13, 2005 | 01:15 AM
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more work but more reliable in my opinion to premix.

pros: more and better lubrication protecting components.

cons: the oil must be changed every 3k miles, not after and checking the oil level and draining excess prior to the 3k mile mark. having to add oil to the tank before every fill up.


you just have to weigh whether you want to be lazy and not premix and just drive or premix and be more reliable with a little added effort.
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Old Dec 13, 2005 | 01:36 AM
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It's a pita premixing, but I love my car enough to go through that for it 2 stroke mixes with gas a lot better than oil, so it lubes better....your car deserves it lol
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Old Dec 13, 2005 | 01:41 AM
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Well since 2-cycle is meant to burn It doesnt leave as much residue in the motor, and I've heard it helps prevent carbon build up. But I hear (don't hold me to this) That its bad for your cats. Ive ran premix on my Tii for 2 years now without a prob. (110,000 miles) Do a search I know this subject has been covered allot, and every thread ends up being a big argument.
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Old Dec 13, 2005 | 01:47 AM
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Originally Posted by RotaryX
Well since 2-cycle is meant to burn It doesnt leave as much residue in the motor, and I've heard it helps prevent carbon build up. But I hear (don't hold me to this) That its bad for your cats. Ive ran premix on my Tii for 2 years now without a prob. (110,000 miles) Do a search I know this subject has been covered allot, and every thread ends up being a big argument.
What cat? lol
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Old Dec 13, 2005 | 02:49 AM
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I thought about going premix about a month ago only because when removing the LIM and UIM I broke two oil lines. I also heard that when running with premix that the engine has alot less carbon build up which I think would be better for when trying to pass smog tests, but have yet to here of anyone doing that. My only problem would be that everytime you put gas in, you will have to guestimate how much two stroke oil to put in but you probably get used to that quick.
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Old Dec 13, 2005 | 08:41 AM
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Preimixing probably adds an additional 3 minites to my refueling time. I just add one oz per gallon, and I measre this by using the marks on the side of the premix bottle. Its not an exact science, so dont overcomplicate it.
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Old Dec 13, 2005 | 10:04 AM
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Having spent the time & money to rebuild my engine, a few minutes every fillup isn't a big deal. It keeps the internals a lot cleaner, and lubricates better. The MOP is a solution for a street car - the Mazda race teams premixed.

The biggest difference I've seen is in having to change oil every ~2000 miles or so because the oil level rises. This is pretty common, and I know my engine wasn't built to the tightest tolerances on the side seals, so I'm not concerned about it, but it does require a bit of attention.

-=Russ=-
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Old Dec 13, 2005 | 11:28 AM
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hey i just want to clarify some stuff for my own comfort as I am thinking about premixing.

1) exactly why would the oil rise and need to be changed on a stricter basis than usual?

2)exactly how much premix is added(i saw someone mention 1 oz per gallon)

3) what is the exact name and Brand of the oil you guys use?
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Old Dec 13, 2005 | 11:35 AM
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Originally Posted by RotaryX
Well since 2-cycle is meant to burn It doesnt leave as much residue in the motor, and I've heard it helps prevent carbon build up. But I hear (don't hold me to this) That its bad for your cats.
welll you have just about every comment in this post wrong or inaccurate.

Modern two stroke oils burn perfectly clean when used in the proper amounts, however too much and you will leave increased build up, and fouled plugs.

But unless otherwised marked all two stroke oil is safe for cat converters even in levels two or three times the normal recommended levels
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Old Dec 13, 2005 | 11:47 AM
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Originally Posted by BklynRX7
hey i just want to clarify some stuff for my own comfort as I am thinking about premixing.

1) exactly why would the oil rise and need to be changed on a stricter basis than usual?

2)exactly how much premix is added(i saw someone mention 1 oz per gallon)

3) what is the exact name and Brand of the oil you guys use?
I just use 1 oz per gallon, and I use whatever I can get at the gas station thats at least TC-3 (rated by the NMMA). That includes most brands (penzoil, castrol, etc..). And I use 1 oz per gallon.
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Old Dec 13, 2005 | 11:48 AM
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Its not that much work...now granted if it is like 2 degrees outside...I could see it starting to suck.

James
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Old Dec 13, 2005 | 12:01 PM
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it also gets semi solid when it's 2 degrees out
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Old Dec 13, 2005 | 12:01 PM
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It is not a PITA and does not take a few minutes. To run premix, just save all the FI cleaner/drygas bottles that you should be using every 3k miles. Those bottles can be reused over and over, and hold 5/8/12/16 ounces depending on the brand. Keep various sizes for different fuel fillup amounts. Bottles with longer necks won't need a funnel.

I keep 5-6 bottles in the trunk. When they're empty, just pick up a gallon of any NMMA-TCW3 oil or API-TC 2-stroke oil, and refill the empty bottles.

If running the OMP, don't overdose the 2-stroke. Run it lean, about 1 ounce for 2-4 gallons of gas.
If MOP is disabled, run 1 ounce per gallon per ~150hp.

I'd wager that premix is more reliable(owner dependent).
The condition of the oil injectors(clogged or failing), the oil injector lines(leaking/clogged) and OMP is questionable after 20 years of neglect.

If you tend to forget, get one of these.
http://www.rotaryaviation.com/oil_in...p_adaptors.htm
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Old Dec 13, 2005 | 12:25 PM
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Yeah. You gotta watch that rising oil. It'll rise up and go out the dipstick hole and .............

Wheeee!
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Old Dec 13, 2005 | 12:28 PM
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Originally Posted by HAILERS
Yeah. You gotta watch that rising oil. It'll rise up and go out the dipstick hole and .............

Wheeee!
Rising oil? From massive blow by?
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Old Dec 13, 2005 | 01:21 PM
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yea my oil definately doesnt rise? what's this about?
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Old Dec 13, 2005 | 01:25 PM
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Not sure, but mine doesnt either.
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Old Dec 13, 2005 | 01:39 PM
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Originally Posted by Wankel7
Its not that much work...now granted if it is like 2 degrees outside...I could see it starting to suck.
Eh, it's not that bad. It sucks a lot less than an engine rebuild.

As for the blowby, I haven't heard a terribly good explanation, but one theory is that the better lubrication lets the side seals "float" on an oil film, and the film slowly squeezes past under the combustion pressure. Whatever it is, the oil level for at least a number of people does go up.

-=Russ=-
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Old Dec 13, 2005 | 02:10 PM
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Originally Posted by HAILERS
Yeah. You gotta watch that rising oil. It'll rise up and go out the dipstick hole and .............

Wheeee!
Just having fun with a earlier post. I've not a clue what the rising oil remark was all about.



'
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Old Dec 13, 2005 | 02:18 PM
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it happens with some engines and i'm not sure what causes the oil to accumulate in the pan, the tolerances in my engine are on the lowest side i could run when i built it and i still get about .5 quart added into my pan ever 1000 miles yet some people do not get any accumulation.

i would have to assume it is attributed to higher RPM driving, i redline my car 3-4 times daily and it gets 100 miles put on it a day.
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Old Dec 13, 2005 | 02:35 PM
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that sounds similar to my driving habits...possibly gas in the oil from work seals?
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Old Dec 13, 2005 | 02:38 PM
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Wierd.. I run my car at the drag strip, and I dont shift until about 7800 under 17 psi of boost, and my oil level is solid as a rock...
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