Modern Vespa

Fired up the ET4 (pre leader, 99) for the first time in about 4 months or so, getting it ready for MOT and checking for spring riding.

Oil level was normal. Oil was reasonably clean. No oil pressure issues (I think, no light, oil was pulled into the engine as per).

I drained the oil to replace and refresh, and there were quite a few small metal flakes in the oil. Brass colour, some silver.

Now, other than that, the scoot seems healthy enough.

Oil used is 20w50 as per recommendations for this engine.

Could it just be a prolonged period of not being used? Or is there something potentially more sinister going on in the bottom end?

Have you owned the Vespa for awhile?

What length rides do you go on?

20w50 is a very thick oil and would likely lead to a lot of engine wear on start up.

Are you sure that's the UK recommendation for oil? And not the oil recommended for Italy with their 40c summers?

I've got a 2022 air cooled 125cc Vespa Sprint and I believe that runs 5w40 in the UK. The first number refers to the thickness when cold and first starting. The second number refers to the thickness once the oil has warmed up.

They're likely very similar engines, so it seems strange to me that there's such a difference in oil recommendation.

Agreed, 20w-50 sounds way to heavy. It should be more like 5w-40 and synthetic if possible. How many miles are on the machine? Pics would help.

The oil weight is what's recommended in the Haynes manual and on Opie Oils.

It's a semi-synth Putoline 20w50.

The scoot has about 4.5k miles on it. But it's 25yo. Mileage checks out based on MOTs and RAC check. Not sure about its service history prior to me buying it, as I got it Cat N (very minor accident damage) from a breaker auction.

It has not been ridden over any considerable distance for a while.

I'd be happy to use a different oil. I've always thought that 20w is heavy for a single cylinder 4 stroke.

20/50 is correct for your scooter, and 5/40 really is too thin for air cooled motor vehicles, which is why it is not recommended by any of the big four for their air cooled vehicles, or Aprilia for their air cooled scooters with Piaggio engines.

Run a magnet through the oil and see what collects, then strain what's left through a sieve or other fine screen. You need to determine what the metal fragments are and where they are coming from.

Thank you for the schoolin', Motovista. I thought about it during the day and I was sure I was wrong and planned on coming back on to delete/change. 5W/40 is what is listed in the owner's manual for my 2007 LX150, which I thought was a bit on the light side.

However, Piaggio DO recommend 5W-40 fully synthetic for the LX150. Page 20 of the service manual:

5w-40 synthetic is prescribed. silver flakes can be babbitt from the main bearing surface. Thicker oil must have been not flowing well through tiny oil channels. Don't want to scare you, but I'd open the crankcase to see what can be salvaged. If say only the flywheel side bearing is damaged, it will be much cheaper fix than to wait for both bearing failure wihich would lead to the entire engine case replacement. Pic. this is how damaged bearing looks like. The shaft rotate in that silvery surface of soft alloy by means of thin oil film that separate surface. The type is called "plain beraring". The slot like hole in the groove supply oil under the preasure. Btw. check the oil preasure, this might be a problem too. should be at least 2 atm on idle.

did nobody else catch that it's a pre LEADER motor? it's supposed to take 20/50...

as to the flakes in the motor, since it doesn't have babbitt bearings then depending on the color of that glitter, it might be the big end of the crank coming apart.

drain & strain to see what you have. refill and run it a short time and then do a another drain & strain to see what you can catch. but honestly, if it's not making a ton of noise, I wouldn't necessarily worry about it.

The Primavera / Sprint are also 5w-40.

Do manufacturers change their specification based on country / climate? I'd imagine a Vespa in Iceland would require a much thinner oil than a Vespa in South Africa for example.

Or has the oil spec been made thinner over time to help emissions, and as synthetic oil tech has improved?

So I ran a magnet through the used oil….

Nothing. Not a speck of metal on the magnet. Gave it a good wipe on a clean paper towel, and there wasn't even much dirt on there.

I mean, obviously that means that there's very little/no ferrous metals in there. But which parts are made with non-ferrous metals?

There were definitely some flakes of metal in the pan after draining the oil… but it's possible these just ended up in the bin after I wiped out the drain pan.

Should I run the oil through a fine filter to see if there's any other metal in it?

I suppose that depends on what you mean by a ton of noise….

https://www.reddit.com/r/Vespa/s/L5F7cmWS8p

I thought this might be the valves. But I did the valve clearances.

Could this be the sound a bearing going?

Sorry, didn't think pre-Leader is that different. I'd love to swap it for my Leader, will check if it will fit into the Lx. No babbitt is much more servisable in case oil pump failure.

The oil pump appears to be fine. The engine has oil pressure. The light goes out quickly on turning the engine over.

Follow Greasy's and Motovista's advice. I missed that it was a pre-Leader engine, so any advice I gave is useless. Sorry.

the leader motor is in every way, shape and form a better motor. the only thing I'd use a pre-leader motor for is a door stop.

My poor little ZAPM0400_!

I had a fiddle round with it yesterday. Redid the valve clearances. Certainly sounds happier.

But yeah, given a do over, and knowing what I know now, I wouldn't buy another pre-leader engined Vespa. It's been nothing but a pain, and knowledge and parts availability are much weaker.

Having experienced the joy of my Honda CBR600f and its similarities to car engines, air cooled or carbed anything can get stuffed.

I mean... the pre-leader is good for what it is. it'll take a near criminal amount of abuse and neglect and still just keep on ticking along. but support is drying up rapidly and the "fan base" really isn't there like on the Hondas and Yamahas

the leader motor is wonderful, I prefer the carb version but the injected variant is just so refined and smooth and peppy it's a hard stance to keep!