Modern Vespa

So I got the new battery installed and was about to go for a ride and enjoy the 60 degree weather. Then I remember the oil light coming on during my last ride. I paid $8.50 for a quart at a gas station and rode it home. So I pulled the dip stick out and nothing showing on it. This was a 10 mile and low oil again, I refilled it and went for a 20 mile ride and low oil again, Nothing on the floor, the water looks clean, so going out the exhaust in a big way. I'm thinking if I have to pull the motor and do the rings and valves I might want to do the malossi upgrade kit, piston, cylinder and head. Just wish I knew a competent Vespa mechanic in middle tennessee. Any suggestions are greatly appreciated.
TIA
Tony

Split from a different thread and gave a new title. OP, if you want to change the title, feel free.

Can you smell it in the exhaust?

Don't forget to check the crankcase breather valve.

Surely there is a sign somewhere of the escape route for this much oil. Burning a quart of oil every 10 miles will attract flashing lights, sirens, and Greenpeace.

The warning light for oil on a GTS is for oil pressure not oil level!

I'm 99% sure there isn't one in a GTS 250. The 500's are where one is vital!`

If it were me, I'd go through the motions for an oil change: drain whatever's in there and fill it so I'd know I was restarting at the right amount of oil.
How often do you check your oil level?

How often do you check your oil level? In 30,000 miles it was never low so I rarely check it. This is the first time I had to add oil between oil changes.

Surely there is a sign somewhere of the escape route,
There is no evidence anywhere, the coolant looks normal, the exhaust is clean, even passed the sniff test, no oil collects on the floor underneath, removed the pet carrier and ran the motor while I looked for something obvious. Everything looks very normal. Engine fires right up, feels like the same power as always.
I am clueless???

You *have* poured it into the sump, not trickled it down the side into the transmission? That've very easy to do if you're not cognisant that the sump filler hole is separate from where the dipstick threads are.

Is the airbox full of oil?

I had an old honda that burned oil at a furious rate but nowhere near 1qt per 10mi. It left a fog as it motored down the road. I I don't think this is burning the oil, its pumping it somewhere.

Did you actually put a quart in?

all the above,

plus are you screwing in the dipstick back in when checking the oil or just placing it back in?

https://modernvespa.com/forum/post2582964#2582964

JimC is 99% spot on. Tony make sure your using a smaller opening funnel and it is just into the dip stick hole ONLY.

you say that you bought a quart... but how much of that did you add to the crank case?

2nd: how do the bubbles on your airbox look?

To be fair, if more than a smidgen went down the wrong way there'd be oil escaping from the rear transmission vent.

I'm angling for not screwing the dipstick fully in. If there's any oil in the two 'bubbles' under the airbox, I bet that's where any excess went.

" Tony make sure your using a smaller opening funnel and it is just into the dip stick hole ONLY." Yes, dip stick only, with a small funnel. I did buy a quart but only a 1/4 or less in each time.. I have about a 1/2 quart left. I have to use pliers to turn the dipstick as it is always that tight. Each time there is none showing on the stick so I pour in enough (into the dipstick hole)to get a reading at the max level on the stick when it is fully screwed in. I do screw it in tight enough so that it requires pliers when I want to check it again.
"Surely there is a sign somewhere of the escape route for this much oil. Burning a quart of oil every 10 miles will attract flashing lights, sirens, and Greenpeace"
I did not burn or loose a quart each time it took only about a 1/4 of a qt. to bring the level up to max on the stick.
There isn't any evidence of oil leaking anywhere. I park on a concrete floor and it stays clean.

I will open the airbox in the morning to inspect that area. Everything else on this scoot seems totally normal!
Thanks everyone for your suggestions. Together we will solve the mystery...

if you're losing 1/4 of a quart in 10miles there is a big time problem. first there would be a noticeable decrease in performance. there would be a gang of smoke coming out of the exhaust-- literally it would be dripping out of the tail pipe; or the airbox would be totally full (hence the bubbles) but with nearly 1/2 a quart in there it would almost assuredly be leaking out or getting sucked into the intake tract, which again, would cause the bike to be running horribly.

so, it's either one of those or it's pushing into the cooling system.

or, the measures are off: the mileage, the amount of oil, the checking of the dipstick.

Greasy said " first there would be a noticeable decrease in performance. there would be a gang of smoke coming out of the exhaust-- literally it would be dripping out of the tail pipe; or the airbox would be totally full (hence the bubbles"
Actually none of that is happening, so a big mystery to me, I did put my 4' level on the floor where the scoot is parked and it is very close to level. I had minor foot surgy today so it will be another day or 3 before I get back to the scoot.

I think we are narrowing in on the cause

Sure there is. I have a good parts table for MP3'250, but it has the same engine and probably the same part numbers. Here #5

I stand well corrected, thanks. I never clocked that as a breather valve, but only as a connector for the breather tube.

Rolf insisted that that wasn't a PCV valve, but… it relieves crank case pressure and (mostly) keeps the oil inside the crank case, so… walks like a duck?

kinda, sorta type thing. PCV is a one way valve that cycles blow-by vapor back into the engine via a port on the intake, usually after the throttle plate using vacuum (this is very generally speaking). where as a breather typically vents the crank case-- usually back into intake tract ahead of the throttle plate, commonly into the air cleaner although it can also be to a catch can or just to atmosphere.

for all intents and purposes, what our bikes have is what I would classify as a breather.

Thanks for the clarification.

EDIT: And why are you posting at 3:30 in the morning!?!

because I needed something to do while I ate my cookies. duh.

Still freezing temps in Middle Tn. This weekend looks much better, I will follow up on these suggestions,
Thanks All!

Jimc said "You *have* poured it into the sump, not trickled it down the side into the transmission? That've very easy to do if you're not cognisant that the sump filler hole is separate from where the dipstick threads are"

This seemed like the most logical explanation so yesterday I removed the transmission cover and found only a few small drops coming out. So today I plan to follow Rolf's advice and check the breather valve and the airbox. I know, I should have done that already but some minor foot/toe surgery is cramping my style.

I have opened up the air filter box, it is very dry. Hose running from the air box to the head, is this the breather valve you guys speak of

Thanks All
Tony[/img][/img]

I buttoned everything back up, rode to the gym and then to Publix (they have really good yogurt), for a total of 50 miles, scoot runs good as ever, oil was a few ounces low but still showing on the lower portion of the dip stick.
Still no evidence of where it is going, today's route will be 100 miles, I will take the remaining 8 ounces of oil with me. Yes, I j\have poured 24 ounces into the engine in less than 200 miles. There was nothing in the air filter, nothing in the sump (variator and clutch)and nothing on the floor. Must be in the water? or exhaust?
Thanks All
Tony

it's in the cooling system or it's in the exhaust then.

hope you cleaned the air filter and box, that looks a sight!

BTW, have you checked your plug?

If the oil breather valve is an actual valve as stated, then there needs to be a separate fresh air intake or a separate exhaust connected to the crankcase, like a car engine. If it is just a connector for the breather tube, then no other vent is necessary. Either way, it doesn't look like the problem in this case.

Cheers,
Bob

it's not an actual valve, it vents via tube into the air box.

greasy beat me to it - pull the plug and post a pic of it.

Ok, I'll do it in the morning, but the exhaust is very clean,

Only time I saw one use oil like crazy was when it had a broken ring. But you could watch the oil flow into the air box. I'm not sure how you could use that much oil and not see it either in the exhaust or in the coolant.

I have been very quiet for a good reason. The oil does not disappear now. I have covered 200 miles w/o needing to add anything. Is it possible my Vespa has AI and knows how to repair itself?

No. Many single cylinder scoots will use more oil if you are blasting down the highway. But if you are just riding around and still losing, there is a reason and it's not going to go away.