Modern Vespa

Personally, I use retaining compound on my seals. Opinions vary, however.

Thanks! Please provide the brand and number type that you use.

Hec

Loctite 680

Grease on the hub seal and oil on the other two.

On your bike, the main seal rubber expands into a 1mm or so groove (where you have that circlip now) to hold it in place.

Several members have recommended Loctite 680 for seal retention. Just got a bottle myself for my V90.


Belt and suspenders.

* In front of.
You have the groove there.

It's a pretty robust groove-locking system, if the gap between the seal and the inner race of the bearing clears .4mm with a feeler gauge.

Unfortunately, Andre's "seals" video is a little vague there.

Rubber seal, right?

Ray,

The main seal is metal. The flywheel side crank seal and axle seals are rubber. I agree that Andre's video could have spent more time on the installation. At one point it looks like he applies green sealant or something to the crankshaft main seal?

Hec


Metal crankshaft main seal

If there's a groove in the cases where the seal sits you need a rubber type seal. The metal seal was presented on the later engines. Also, there are two seals for the rear hub 27mm & 30mm depending on the brake drum you have…

SaFiS,

Mine has the groove however Scooter West recommends a metal seal over the all rubber seal. See video.
That's why I went with it. In the video he installs it pretty much dry. I also saw that in Robot's P200 restoration video he uses grease on all bearings except the main Crankshaft seal. It went in dry as well. Sounds like it's a matter of preference.

As for the axle seal I have the correct 27mm seal .


Hec
Go to 50:10s mark
Go to 55:16s mark

Problem with the metal seal is that it gets too compressed in the old cases, resulting in deforming and often touching the center race of the clutch bearing. If that happens it will rotate and pop out…

I toldja opinions vary

While it may be correlation rather than causation, I've never had a seal fail on it perimeter when I installed it with retaining compound. And I always use the rubber edge seal if it's an option. I've seen too many metal seals spin loose to trust them.

How hard is it to remove a metal oil seal that was installed using Loctite 680? Just thinking of down the road.

Hec

Not enough harder that it matters. They all come out pretty easily with a little bit of tough love from a hammer and punch, pliers, or screwdriver.

Not hard at all, you normally can remove it with a flat blade screwdriver. If it's tight, the loctite tech sheet says heat it up to remove. But that's just playing it safe.

It's more to hold it in place and stop it spinning. And there's not much space for it to hang onto.

But I wouldn't put a metal seal in an engine with a groove. There's not enough material for the metal seal to hold onto. And if it's a PX case, the likely hood of you needed to trim 0.5mm for it to sit flush and proper, are high.

It's important or the bearing will spin and pop the seal out. If it stays in place, it'll create an air leak…

BGM and malossi make metal seals which are the right size.

Just fyi, like the videos mention, installing a metal seal is a bit of a pain because they buckle as you push them in… got to be slow to make sure it goes it straight. Having the right SIP tool helps.

You guys have convinced me to go with an all rubber seal. The groove to catch the rubber seal is mint on this case and very clean so it should do its job!
This is the one I am thinking of getting from Scooter Mercato.

https://www.scootermercato.com/112156

Any issues with this seal? Is there a better all rubber seal?

Question: I'm not sure what it's proper name is. They are circled in yellow in the picture. Bearing Retainers? The nut on the on the left was loose and the nut on the right wasn't exactly tight. The inboard metal tabs where folded so that they contacted the nut. This picture was taken just after splitting the cases.

Should I use Loctite Blue here and possibly a lock washer? Don't want them falling off!

Once again I appreciate your comments!

Hec


Nuts Loose

I'd go for a tried and tested corteco seal.

Just for peace of mind, of course that's just personal preference and I'd be looking at go-fast upgrades.

Malossi or BGM seal if you can get ahold of one.

Your build isn't that crazy, but I'd run a blue cortico at minimum.

Plates retain the bearing, tabs are the "lock washers". Take it all apart and clean it, you don't want any gunk hiding in there getting into the motor.

Reassemble with loctite and torque em up and peen the tabs back.

The malossi seal you have will fit in your case, as long as using loctite 638 or 680. And surgically clean before sticking.
These seals fit tight and don't rub the bearing.

If you must have a full rubber seal, then this is the only one I fit. In a performance build.
https://www.scooter-center.com/en/oil-seal-31x62-1x5-8/4-3mm-bgm-pro-fkm/viton-e10/etahnol-resistant-rubber-brown-used-for-crankshaft-drive-side-vespa-px-1984-rally180-vsd1t-rally200-vse1t-sprint-veloce-150-vlb1t-294260-super150-vbc1t-412374-ts-vnl3t-bgm1004?number=BGM1004

This seal should be available locally in the US.

greasy125,

Thanks man! That's what I'll do. I have everything pretty clean!

Thanks Jack!
I'll look around for the one you posted! Not having luck finding it in the States though.

I called around and the Seal sold by Scooter Mercato is a Rolf brand. Scooter West sells an RMS brand.

Here is another observation.
I assembled my axle gear stack and used an SIP 2.5mm spacer shim. I now have approximately 0.25mm of float clearance. I know the specification is 0.15mm to 0.40mm of float. I'm right in the middle of spec. Does that much wear seem excessive for 6,500 miles? I know when I got it there wasn't much oil in the gear case.

Hec


Bearing Retainers all cleaned up


Last edited by Hec In Omaha on Mon, 27 Feb 2023 18:28:36 +0000; edited 2 times

Sorry to barge in, but I was wondering about the clutch side seal for the P200e. The hub seal in this kit might be the wrong size, but I have spare Cortecos for the hub.

https://www.scootermercato.com/M-6617310

orwell84

That's the same kit I bought except mine is the 27mm hub version. I wonder if the Rolf, Corteco, and DNS seals are viton and therefore Ethanol Resistant? If they aren't I think I'll end up using the seal I have.

Hec

My Seal Kit


Malossi Seal Kit

Scooter-speed carries the SIP-branded (Corteco) blue seal.
Mark usually ships same day.

While you wait, to might want to consider getting a sealant to at least apply around the crank gasket surface on the small half (and fit/position the gasket on the small half first).
There's a 1.5mm meat-wise weak point, next to the kickstart gear.

Amazon carries Dirko HT, etc.

https://scooter-speed.com/vespa-engine-oil-seal-crankshaft-clutch-side-sip-premium-t5-px-pe-rally-v12k-13110200/

https://www.amazon.com/Elring-Replacement-Rocker-Gasket-036161/dp/B0068NKY2C/ref=asc_df_B0068NKY2C/?tag=hyprod-20&linkCode=df0&hvadid=312098740701&hvpos=&hvnetw=g&hvrand=7259727670404688114&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9030955&hvtargid=pla-571647242635&psc=1

Well - since everyone else shared their view…

I only use Viton seals.
It's a brand for a rubber compound that is the best stuff around.

They are usually brown.
Sometimes black.
Ugly but tough as nails.
Jack's link for the BGM one is viton.
As he noted - they are standard seals - u may find them on Amazon even.

Just need to know the width and diameter.
My $.02.
Viton only on crank seals of any kind for me.

Thanks I'll hit Scooter Speed tomorrow! They are closed today!

Are you saying I should build up the thin ledge on the right case to make it wider with the sealant? Is this the area of the case you are referencing?

Hec


Sealing Surface

I'm fairly certain he meant not to build it but to seal it because the area is thin and not everybody used gasket sealant on the case gaskets.

I wouldn't sweat it, the middle is just fine and that's totally in line for the mileage. excessively low oil and run for a duration would show wear on the axle and gears interface and the gear teeth more than on the side faces.

you also changed your 4th gear too, correct? that would affect the stack height as well.

either way, no big deal because if the components look good and you're in spec then just ship it.

Greasy,

I thought he was referring to FMP's oil sucker trick. See video. Looks like FMP not only sealed the case gasket to the right case with sealant, but he Betty Crocker'd the sealant to shore up the thin area.


Go to time marker 5:42s
As for the gear float I guess I'm OK with being in he middle of Spec. Yes I changed 4th gear to a 36 Tooth.

Hec

There is a good freak moped video on case sealing. He goes over doing this area.

Video so nice it was posted twice!

There's a 1.5mm meat-wise weak point, next to the kickstart gear.

Ray,

You're right! Mine measured 1.53mm at the thin spot. Sheez I hope I can make a good seal there. I may have to utilize my Betty Crockering Skills with the sealant!


Pretty Thin!

Thin!


Last edited by Hec In Omaha on Tue, 28 Feb 2023 18:02:31 +0000; edited 2 times

Here's pictures of the gears. I think 1st gear shows the most wear where the Cruciform makes contact. How do they look?

Hec


Gears

1st Gear

2nd Gear

3rd Gear

think about how the cross interfaces into the gears, that's where you want to look for wear. the lands should be fairly straight, with nice 90 edges and no chips, worn gears eat up crosses fast and then worn crosses beat up good gears.

if you want to throw some pics of that part of the gears I'm happy to look.

Greasy,
Thanks for the offer! I'm not sure I can get close ups that are good enough. I tried and hope these pics will work. I didn't see chips or gouges in the lands. As far as I can tell, only first gear is showing rounding in the corners of the lands. All other gears lands look nice and square similar to those on the new 36T Fourth gear. I have included pics of the old Cruciform too. One more bit of info, the gear spacer shim that was previously installed was a 2.20mm spacer. So someone has been in there as it's oversized. I believe standard thickness is 2.0mm.

Ray8

Thanks for the link for the sealant! I ordered it and it arrives tomorrow. I hope I don't end up with a gear sucker.

All,
I contacted Scooter West regarding the metal crankshaft seal being installed dry in their videos. They said "Metal crankshaft seals can be installed with or without sealant. They do not use sealant at the factory and we do not make it a practice of using sealant." I suppose if customers were coming back with spun seals they'd use sealant. Makes sense to me.

Hec


Original Cruciform

Original Cruciform

First Gear

First Gear

First Gear

First Gear

First Gear

First Gear

That 1st cog could go back in the packing and be sold as new.
Put the fatest shim near to 4th gear.

If you ask enough people about the seal you'll have no idea what to do. If it will ever have performance upgrades, a viton seal is better and with loctite has greater success.

^^^

like jack says, fine and dandy to run.

stop overthinking it with the seal. metal, loctite it in. rubber, if you have the groove is fine without loctite. ior put a dab on if it makes you sleep better at night.

viton, metal, rubber, whatever it doesn't matter. it's not an all out performance build and more than likely you're going to have the cases split before the seal gives up the ghost. unless you installed it incorrectly, that is.

resign yourself to the fact that no matter how hard you try and what steps you take it's almost never a one and done with these motors. it's not like a 350 that goes 100K without a hiccup. you'll be cracking the cases again.

^^^^^

This, for sure.

Any given engine has many opinions for every part and procedure.

I am like you and still suffer from analysis paralysis. I approach Vespas like automotive engines where there are many things to remove and take apart before you can crack the case.

But these engines are way different. You can split the case in the frame if you want. Once you have done it a couple times, you can have the engine on the bench in about 20 minutes. You're doing good.

Ok ok! Yes my OCD has kicked in regarding seals! I have 3 other Italian Scooters I picked up that wouldn't run due to one seal failure or another. Sometimes it was an old O-Ring that failed. Sometimes it was a failure of a mechanical seal. It only takes one drop of water in the wrong place and this thing won't run and leaving you swimming home! What the Hec am I talking about? It's called an Aqua-Scooter! It's Italian made and as far as I know it's the only internal combustion engine that runs while completely submerged. They are 2-Stroke! The carb, spark plug, exhaust, ignition system, fuel tank is completely submerged. It can operate up to 4 feet underwater with a snorkel extension. I thought I'd share my other Italian Scooters with you guys! Yes I love to tinker!

Hec


Aqua-Scooter internals. It had a broken crankshaft caused by a guy trying to pull start it with the Cylinder full of water. It was given to me after that. Still runs great after 5 years!

My three Aqua-Scooters

My youngest with hers!

Mine!

Cut the tip of the dispenser tube so you can only apply a small (1-2mm?) bead. Don't smear it with your finger. Fit the gasket snug at the weak spot and smooth it out with a large screwdriver.

I only used it around the weak spot with the same gasket you have. It's really more of a positional lock vs grease, & a cheap insurance policy. There's too much play with those bolt holes and a dry gasket on these cases.

Btw that FMP Dirko slather video involves beer

Surprised to see that response from SW
If you still have the seal you removed you can see where the rubber expanded into the groove. Or what the hec, buy two and try to pull the first a day later.

Andre used 2t oil on perimeter of that SIP seal, 20+hp build. If you use loctite I won't have to take any blame
Just don't use a metal seal

Ray8

I see what you mean. The old seal does have the expanded groove! I'll be calling Scooter Speed for an all rubber DGM Viton Seal!

Thanks!

Hec


Old seal expanded groove

All,

Going back in time. Here is a pic of the engine after I pulled the right side case off. Look at all the sludge at the bottom! There was a lot of sludge at the base of the cylinder too. So I ask, what's your take on the cause of what you see here? Is this typical?

The BGM crankshaft Viton seal is on the way from Scooter Speed. Thanks Ray 8 for recommending Scooter Speed! I had to buy the 3-seal set to get it. It maybe the only one for sale in the United States! It was Scooter Speed's only one! Don't know what I'll do with the Malossi Viton Kit I have now.
I also bought a main jet assortment from them. Main jet kit -BGM PRO Dellorto SI- (115-138) - (115-118-120-122-125-128-130-132-135-138) . I'm sure I'll need a MJ in that range.

Hec

Thanks in advance!


Engine after splitting