Modern Vespa

I've never understood why. Is it for aesthetic purposes? I've found that just a good brushing down with straight gasoline works fine. They just get grungy again within a week.

Anyway, those cases look good.

A couple reasons.
1. I think it leads to a better and more meticulous rebuild. Clean ass cases will inspire ya to chase threads and take the extra care you might not otherwise invest.

2. It's truly easier to spot case defects, cracks, weirdness, etc on vapor blasted cases.


MHO, YMMV, FWIW

#2 two sounds very valid. I hadn't thought of that.

money spent on vapor blasting is less money for ham!

adios the kick starter and just bump start it. enjoyment from the ride AND a work out!

If only I was 20 years younger.

#3 Vapor blasting "seals" the surfaces so they don't get dirty that easily anymore...

You're doing a pristine resto, it would be a shame for the engine to look like "crap" even cleaned up...

Hmmm…

Important little paragraph from the service station manual regarding cage and conrods matching. Apparently SS and Rally don't follow the usual protocol.

Where does one obtain a service station manual?

There are some printed pdf copies for cheap on fleabay. OG manuals are tough to find, but come on market from time to time. PDF versions are out there on the webs for download... you have to dig, but I think most are out there.

EX -
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwiezvjkzrX7AhXmk2oFHefMAx0QFnoECDwQAQ&url=https%3A%2F%2Fwww.vespaforum.com%2Fmanuals%2FMore%2520Manuals%2FVespa%2FPX_150_Workshop.pdf&usg=AOvVaw0Z8hSKHls2VWrkhY0ec74m

This was/is my goto-

http://online.fliphtml5.com/qtjt/rbak/#p=14

^^^
There it is... I knew it was out there somewhere!!!

Cool, thanks!

So a "4th category" con rod takes a "1st category" cage?!

That's some impressive product labeling logic.

I assure you the production engineers did that on a Friday at like 4:30pm, drunk on Barolo and laughing hysterically as they wrote the copy for the service manuals. Fuckers.

I see it's missing pages 7-9. Just like my copy 😢

Replacement cases being prepped…

The exhaust bolt is stuck in place and looks like it got pretty worked over at some point.

I have had penetrant on it for a few days now…
Is it reasonable to heat up the case and then try and use an impact wrench to remove?

Worried about rounding the head further and/or damaging the case with the power of the impact wrench.

Thoughts?

I would. Even worst case you drill and tap if it goes sideways

Without a doubt, get the bolt hot, hot, hot!!!...just like the Cure! Get out the propane torch and focus most of the heat on that bolt. The rest of the heat will dissipate to the cases which won't be a problem. You might have to repeat the process a couple times until the bolt comes out in one piece though.

No! Stop! Don't do it!

Heating the case is the wrong technique.

Like whodats says, you need to heat the bolt, not the case. Focus a MAPP torch on the bolt . Get it red hot then back it out back it slowly.

Yeah, don't pull a stunt like I did and break something. Next time I run across this issue that bolt is gonna be so hot it'll want to melt out of the hole

Wait a minute...
He should focus the heat on the aluminum, no?

Baby steps and leverage will get the job done.
TIGHT Vice Grip on a shot bolt head -- and something to add more leverage as needed, like a big wrench on the vice grip.
Aluminum doesn't fuse to steel. It's all corrosion friction.

BTW I went through this a month or so ago. Tried freeze spray I'd ordered by accident, for the hell of it. My garage still wreaks of this shit:
https://www.amazon.com/CRC-05002-Freeze-Off-Super-Penetrant/dp/B000TFTH00/ref=sr_1_2?crid=29YNFSI1A6VDO&keywords=Freeze-Off+Super+Penetrant&qid=1668886626&s=industrial&sprefix=freeze-off+super+penetrant%2Cindustrial%2C196&sr=1-2

Can you weld? Tack weld another nut to the top of the stripped bolt.

Plan B: https://www.harborfreight.com/38-in-drive-metric-bolt-extractor-socket-set-9-piece-67894.html?utm_source=google&utm_medium=cpc&utm_campaign=12169518939&campaignid=12169518939&utm_content=114845770017&adsetid=114845770017&product=67894&store=164&gclid=CjwKCAiAmuKbBhA2EiwAxQnt72xo1HhtGxPeQmrWu2cyEOH2-E8mel0Yz1WVT9jXdjEwc8f-ThR0thoCOQ4QAvD_BwE

The aluminum is going to get dang hot as well, so i usually just focus the majority of the heat on the steel bolt. If the bolt doesn't come out, then i just kinda play it by ear after that.

No. I was advised by a very experienced machinist that the correct technique is to heat the steel bolt, not the aluminum. I've tried it many times and it works.

I'm guessing about the physics but I suspect heating the bolt expands both the bolt and the material the bolt is screwed into but at different rates. Heating the bolt also cooks off any thread locker that might be on there.

Thanks for the replies y'all.

Will give it a go in the morning.

This is all quite odd. On an SS180 (or GS160), a bolt should not thread into the case arm. It's a long bolt that pushes through the case arm and threads into a square caged nut in the exhaust bracket. That looks like a bodge by a previous owner.

Maybe you know this, and you are a doing a rescue job. I don't know.

The bolt that needs to be there is like this one:

https://www.ebay.com/itm/174211982181?hash=item288fd7e365:g:eMEAAOSwNNVeR1po&amdata=enc%3AAQAHAAAAsG5cnRIDkC%2FSVOyWc6LpTkg61yxMsTHEV27zldUQKLH0rRuhs9jPHJyhyYHJyFRLinwGJ0x2YxTptQi8V6zed38tQhtWij3N9m%2BUKN9QdX%2FqsaF6PRgKPZKFxoeswhe6JMy9li5QlW%2FHK9yPJ%2FARpghNAGUCv8vxtDloGL65QlZbwlef4sOWMI%2FZ6b%2B0g%2F8psZNwXswsOdYW1lwB5BMxupzjSQbGsBHIR%2B%2FEMlhddJBV%7Ctkp%3ABk9SR66ohM6SYQ

This is a new set of cases I just got… I don't know if it is the correct bolt or the incorrect bolt. I just know the bolt is stuck fast in the swing arm… We'll see what's-what when we get the bastard out!

Well, all I'm saying is it ain't right the way it is at the moment.

Does your old engine swing arm have the same?

Just rust and crust. Had to remove the swing arm mounts to get penetrant in there, and it was a two man job for sure. Mark - usual suspect - with the assist. Thanks man! Onwards.

Next order of business…

There is a very particular roller bearing in the SS that requires a very particular tool. (Typical blind bearing pullers WILL NOT work.)

Anybody out there have the factory tool pictured below? Or know someone who does? I'll send ya a monetary deposit to borrow, or the case half and some ducats if you'd be so kind.

Ah, I see now that the exhaust bolt is the right one and wasn't threaded in. It was just broken and fused in.

Sorry, but I don't have that puller.

What's the ID of that bearing? I don't have that puller but may have one that could work.

ID looks like it is 21.3 +/- 0.15

It has a weird brass bush that is press fit into the case and sits proud internally, hence the need for the specialty tool. Mark and Jonathan both suggested tack welding a bolt to yank it out, like on a smallie... would prefer the tool or similar if possible. (The standard blind bearing puller can't get purchase bc of the brass.)

Would the bread method work here?

Mark found a version on SIPs website

https://www.sip-scootershop.com/en/product/tool-puller-sip-bearing-flywheel-side-input-shaft_21467280

(Fine…. Finnnnne… it's fine.)
*lights 100 dollar bill on fire* Burning bread method as in burning cash? ....yes

I don't think the bread method is possible here as tapping on a bolt would probably damage the brass receiver for the input shaft.

Tool finally arrived! What a weird little extractor. The bearing wouldn't come out without heating the case… but popped out with the puller after some time in the oven.

If anyone ever needs to borrow… I'm your huckleberry.

Peeks in…

There may have been some vapor blasting completed on my Quebec cases:

Nice!

Vapor blasting is my new Frank's Red Hot for engine rebuilds...put that sh*t on everything. So nice to work with clean parts versus weird hydrocarbons leeching out of the block forever.

Very nice indeed!