2012 50cc Super 8 2T Oil Pump

[netlag]

Been advised that my oil pump is no longer functioning, so have been premixing since then

Scoot has 11.5k mileage... so it seems probable that it is a mechanical issue and will probably just order another pump.

Before I order... thought to double check my oil bleeding technique against what others commonly do.

Also, who seems to be the lowest cost dealer for Kymco parts?

[netlag]

Argh. For some reason my oil light is now illuminated and the resivuor seems to be a little less enpty from a day ago. All since removing the lines from the carb a day ago.

Really not sure what to think about this since it has not been working since it was primed two weeks ago. Again, today the light is suddenly illuminated and there seems to be less oil in the tank.

Is this behavior common with bad, or going bad pump?

Lastly, since I have one on order... How difficult is it to remove replace the pump?

Quick glance at the project leads me to believe the cross-member above the pump would be in the way. Must the engine subframe be seperated from frame to allow clearnce for the pump's camshaft during a remove and installation?

[eamartin]

Did you cap or plug the oil line from the pump to the carb?  Is there an oily mess down there someplace?

[netlag]

Nope to either EAMatin. And, the light went off again. Was probably wishfull thinking on my part or just the light's reaction to the off-level the center stand produced.

[netlag]

bump

[netlag]

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[CROSSBOLT]

Usually when there is no response on this forum it is because we don't know the answer. I don't know the specifics of this scooter but did have a Yamaha YM-1 2t motorcycle in the 60's with "oil injection" that worked really well. That quart + tank would last a month of everyday riding! Now, if they would have had an ignition system that worked as well as the lube system, that would have been a really great bike! Had plenty of advice to remove that pump and go back to mixing. All those jokers were afraid the pump would fail and fry the engine. Well, it never failed and I put 20000+ miles on her before I parked it. How do these people you are talking to know this pump is not working?

[netlag]

Usually when there is no response on this forum it is because we don't know the answer. I don't know the specifics of this scooter but did have a Yamaha YM-1 2t motorcycle in the 60's with "oil injection" that worked really well. That quart + tank would last a month of everyday riding! Now, if they would have had an ignition system that worked as well as the lube system, that would have been a really great bike! Had plenty of advice to remove that pump and go back to mixing. All those jokers were afraid the pump would fail and fry the engine. Well, it never failed and I put 20000+ miles on her before I parked it. How do these people you are talking to know this pump is not working?

Ahh, ok. Figured someone would have replaced one of these by now, or at least have had more experience troubleshooting an oiling issue on a 50 cc then me.

History is that the issue was determined after a sort of field test by a shop-owner "mechanic". For some reason I was curious about the diagnosis, so thought to double check it as I plan to do a remove / replace soon.

Method I chose to determine this IIRC was checking all of the lines by blowing through them. Priming lines that needed it. Checking the gravity line from the oil tank. Checking vacuum at manifold.. etc.

Ordered the pump as it seems there is no oil being pumped/sucked past the oiler.

Won't be able to check the gear until it is pulled.

Anyways... Understand that the oiler is not serviceable either for this motor. So, suppose it will be what it is to remove and replace.

I am premixing until then.

[Chris0381]

Oil pumps rarely go because they are lubed constantly. The manual gives a somewhat idea of how to bleed the pump. But at the end of the day if you crank or run the scooter briefly with the oil line disconnected from the carb, you should see a dribble of oil coming out. The oil comes out of the bottom of the reservoir so getting the air out of the line going into the pump should be fairly easy using gravity (letting the oil run thru the line via gravity then plugging it into the inlet side of the oil pump).

[netlag]

Oil pumps rarely go because they are lubed constantly. The manual gives a somewhat idea of how to bleed the pump. But at the end of the day if you crank or run the scooter briefly with the oil line disconnected from the carb, you should see a dribble of oil coming out. The oil comes out of the bottom of the reservoir so getting the air out of the line going into the pump should be fairly easy using gravity (letting the oil run thru the line via gravity then plugging it into the inlet side of the oil pump).

thanks. IIRC dribble test produced nil too. Guess I did cover all of the basics.

[eamartin]

thanks. IIRC dribble test produced nil too. Guess I did cover all of the basics.

When I have done "the dribble test", if the cable was not properly adjusted I might not get any oil from the pump at idle.  By running at higher rpm's i would start to get oil.  But I don't get a dribble.  While my notes are not in front of me, my recollection is of maybe 6 or 8 drops per minute.  It takes a lot of patience to test this.   And if there is any air in the lines it takes quite a while before the drips begin.

[Chris0381]

When I have done "the dribble test", if the cable was not properly adjusted I might not get any oil from the pump at idle.  By running at higher rpm's i would start to get oil.  But I don't get a dribble.  While my notes are not in front of me, my recollection is of maybe 6 or 8 drops per minute.  It takes a lot of patience to test this.   And if there is any air in the lines it takes quite a while before the drips begin.

Thanks for mentioning this as I forgot. There should be marking on the oil pump cable cam that line up with another mark if the oil pump cable tension (length) is correct. The cam has to be operated (turned) a certain amount before oil will be allowed to flow to the carb. There is a cable adjustment screw I believe to get the correct cable tension (length). If the cable is too loose, the cam will not be operated enough to allow oil to flow to the carb.

[netlag]

Thanks for mentioning this as I forgot. There should be marking on the oil pump cable cam that line up with another mark if the oil pump cable tension (length) is correct. The cam has to be operated (turned) a certain amount before oil will be allowed to flow to the carb. There is a cable adjustment screw I believe to get the correct cable tension (length). If the cable is too loose, the cam will not be operated enough to allow oil to flow to the carb.

Thanks for the info. Alot of info that is not in the service manual!

Will check where the alignment marks are before removal.

Don't recall there being any sort of adjuster for cable tension, but will check that out when the box is out too...

Will be checking the new oiler out to understand the cam-bracket adjustment mentioned.

[Chris0381]

There are a few gurus on here that I dont see much any more that did mention, you should upjet once you mod the snorkel and exhaust. 85 seemed a sweet spot . I up jetted even more when I opened up the box and never bothered to down jet again.

[netlag]

There are a few gurus on here that I dont see much any more that did mention, you should upjet once you mod the snorkel and exhaust. 85 seemed a sweet spot . I up jetted even more when I opened up the box and never bothered to down jet again.

.

Removed and replaced the pump today.

Not sure how the "drip" test works for you all with no vacuum. Found that by removing the plate on the old one..these things are really like a meter vs pump as there is no push. Oil is vacuumed to the intake manf and the carb. No wonder there is no flow, drip, or drop. Learned that there is a  metering dial in the pump which turns only slightly when the cam is turned...not enough to create any sort of "push".

Supoose also that the old pump had some garbage in the chamber under the brass fitting (outlet). Not going to bother wasting wd-40 to check if the blindspot can be cleaned.

Since installing can see that engine is getting oil now from both the pump and  premix. Thankfully, I only have 1/4 tank premix left.

Suppose next project will be the 85 jet, so back to my tuning post I go.