Mongoose 50 Oil/fuel question.

[dmcleaner]

I picked up a 2005 Mongoose 50 this week (I traded for a ktm 50). My kids love it. The previuos owner had the engine resleeved and new piston/rings, etc. He said the mechanic told him that the oil injector had malfunctioned. Is that common or possible? The cable seems to be intact. The old owner simply added oil to his gas (32:1) AND filled his injector tank. It runs fine, but sometimes smokes more than other times. I guess I have a few questions....here they are:

1. Can the injector work off and on from time to time, and if so, how to check and fix?
2. If I run oil/gas mixture, what would be correct ratio?
3. Would I have to disconnect the cable from injector, or simply leave be?

Any insight would be greatly appreciated!

[Shaka]

Those oil pumps do go bad!  They are a very common cause of engine seizure!  You can premix the fuel, probably want a ratio of 40:1.  Otherwise, it would be wise to add a little extra to the tank on fill up if you're still going to keep the pump connected.  You may also try wiring the pump full open and adding oil to the gas tank as well.  Personally, I just run straight premix.  That way I can be certain of the exact amount of oil the engine is getting!  If you want to disconnect the pump you can just un-hook the cable and cap the inlet & outlet.  Some people also pull the pump out and remove the gear so it's not spinning and robbing the engine of power.

[zombie]

1. Can the injector work off and on from time to time, and if so, how to check and fix?   There is a screen at the base of the oil tank, If the scoot is new to you I would start w/ getting ALL the tune up parts. Don't let him ride it until he reads enough to see what may? be wrong. I would hATE to see a kid turned off cause of lack of maintenance. I run my pump wired open, and add appox. 1/2-3/4oz of 2t per tank.

[dmcleaner]

Thanks buds. Here's my plan...I am going to leave the injector in place, cable and all, run premix 40:1, and let the oil run out of the tank 'til empty. Then I will simply run premix 32:1. How's that sound?

[Shaka]

First off, you don't need to run that much oil, 40:1 is fine.
Second, you will need to cap off the inlet to the carb after there is no more oil left in the tank, as it will suck in air otherwise leaning your air/fuel mix.

[zombie]

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