Smallframe engine build - 1974 Primavera
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Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Mon Jan 20, 2014 10:53 pm quote
Hi all, just getting started on a rebuild for my smallframe engine. The trans keeps popping out of gear when I select 2nd or 3rd, so I'm suspecting worn cruciform / selector spring.

I pulled the engine out the other day and got it on the bench. All the write-ups I see start with pulling the head and cylinder, but I don't have an impact, so I decided to use the rope trick to hold the piston and get off the flywheel, clutch nut, and primary gear nut before pulling the head.

First up, the flywheel came off. Make note of where the stator is in case the marks get cleaned off. In this case, a previous owner has marked 20 degrees BTDC with the marker marks. I think a photo with the casting numbers is a good reference to have:


I made a diagram of the stator connections before pulling it out. The helpful folks at Piaggo or some previous owner used 3 of the same color wires, so I marked them with a Sharpie and dots to be able to put them back later. The wiring insulation is cracking apart near the junction box on more than one wire. I may opt to have the stator rewired or just get all soldery on it myself.

I pulled the clutch cover. I recently changed this clutch. I was surprised to find kind of a brassy mess under here. I wonder if I had the plunger adjusted too tight or if there is a fitment issue? Comments are welcome. I usually adjust so there is about 1/4" free play at the clutch lever before you feel something happen. I might have got it wrong but I didn't think so.



Here's a closeup after they are cleaned up:


I used the clutch puller tool to grab out the clutch since the top end was still locked. Then I pulled the primary gear as well.

I took a pic to remember which way the gear goes on:


Last edited by sdjohn on Mon Jan 20, 2014 11:05 pm; edited 2 times in total
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Mon Jan 20, 2014 10:58 pm quote
Now with all the tough to remove nuts off, I can pull the top end. I hadn't pulled the intake manifold or exhaust manifold, so those went first. A previous owner used a bit too much loctite on the intake, so the stud came out with the nut.



With the head pulled, I see that someone has used sealant on the head. I'm not sure what it is, it's blue. Is this good practice? I'm all right with it if it's common. At any rate, it wasn't leaking so it worked.


Bore looks good, it's a standard Primavera top end with 2 ports. I found 4 nuts and 7 washers afterward, it looks like one is missing. Are these wavy washers? It looks like wavy washers and standards, but the wavys are now so flat you can't tell.

Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Mon Jan 20, 2014 11:01 pm quote
With that done, I pulled the piston. Rings are free, some blowby but nothing too scary.


Then I made a diagram showing all the case bolts and whether a nut or a bolt head faced the flywheel side. I took measurements of the bolts as they came out and noted them on the sheet for later.



I pulled all the case bolts and nuts. It looks like 2 of them are studs into the case. A few gentle whacks with a rubber mallet yielded no results, so I'm off to go read the "How to Restore Your Smallframe Vespa" book again and see what the tricks are for splitting them without being a hack.

-John
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Mon Jan 20, 2014 11:04 pm quote
I'll have to search again for the threads on engine stands too. Pulling apart the engine is one thing but I want a stand to put it together again!
Molto Verboso
Joined: 24 Jan 2008
Posts: 1909
Location: Santa Margarita,Ca.
Tue Jan 21, 2014 10:25 am quote
There is a locating dowel at the lower rear of the engine that fits snug. Piaggio has left a lip on the fly side to tap on there. Alternate with a tap to the back of the air duct area up top. Rubber mallet of course. Unless someone has changed it, the fly side bearing is 2 pieces.
Ossessionato
73 Rally, 74 Rally, 76 ET3, 80 P200, 63 Li125, 65 Li225 Silver Special, 86 Elite 80, 2015 HD Road Glide Special, 2011 Ural Tourist
Joined: 18 Jan 2012
Posts: 3305
Location: Oceanside/ SF
Tue Jan 21, 2014 2:59 pm quote
Good times man. I'm also tearing into an Allstate.

I've been using the How to book but also using http://www.smallframes.com/tech.htm for reference.

Looking forward to your results
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Tue Jan 21, 2014 3:47 pm quote
Thanks Marc and MJ. I forgot to go look back at the smallframes.com pages, they are a good reference. I will give a go again tonight, minding that dowel and using a rubber mallet gently.
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Tue Jan 21, 2014 8:28 pm quote
I picked up trying to split the cases and quickly realized I'd missed one fastener, thus making my fancy drawing useless because I'd got off number due to the missing fastener on the drawing. Whatever. They're easy to figure out due to the flats to hold the bolt head.

So with that out, the cases split finally!

IMG_0253 by john.headley, on Flickr


I pulled the christmas tree to find that it was covered in bits of kickstart buffer.

IMG_0254 by john.headley, on Flickr


Removed the circlip and tabbed washer thing from the gearbox, then out with the loose gears.

IMG_0255 by john.headley, on Flickr


IMG_0257 by john.headley, on Flickr

Out with the kickstart.


IMG_0259 by john.headley, on Flickr

I had a hard time with the concept of using a screwdriver on this but it turned out to work OK and was fairly easy.

Pulled the gearchange mechanism.

IMG_0262 by john.headley, on Flickr

Out with the kickstart cog, spring, and dished washer.

IMG_0263 by john.headley, on Flickr


IMG_0266 by john.headley, on Flickr

Then push out the clutch basket.

Out with the crank.

IMG_0269 by john.headley, on Flickr

Out with the clutch side seal, mine didn't look too hot but I don't think this really affected sealing.


IMG_0270 by john.headley, on Flickr

The book says to use heat and whack the case against a work surface to get the fly side bearings out. It worked for the Christmas tree bearing but not for the driveshaft bearing. I didn't try the crank bearing race.


IMG_0272 by john.headley, on Flickr

This sucker's had it, I think.


IMG_0273 by john.headley, on Flickr

Some scoring on the rotary pad but it doesn't feel deep.


IMG_0274 by john.headley, on Flickr

OK, so today's questions.

1) The book suggests destroying the small roller bearing for the drive shaft if it won't pop out. If mine rolls OK, is it OK to leave and reuse?
2) I don't have a split bearing puller and I'm leaning toward reusing the fly side bearing and race. This will most likely save me damaging the crankshaft and case. Since it rolls fine, this is my inclination. Is this sensible?
3) Where do you find bearing drifts this large? I used the inner race to push them out but I don't want to use it to push them in. They are bigger than my socket collection!
Molto Verboso
Joined: 24 Jan 2008
Posts: 1909
Location: Santa Margarita,Ca.
Tue Jan 21, 2014 10:08 pm quote
Most reuse the driveshaft roller bearing if it's not damaged or corroded.

The flyside bearing is pretty stout and also expensive. Mileage would be a factor. As would any play at the flywheel. If it has a plastic retainer I'd replace it. Actually, I'd replace it anyway, but you might be fine givin your level of tune.

The old bearings can be used to set the new ones. with the right amount of heat they gennerally just drop in. Or you could just bring it to motorsport and pay them to do it.
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Wed Jan 22, 2014 6:02 am quote
Can anyone link me to a split bearing puller that would fit the crank fly side? Maybe it's worth buying the tool.
Sergeant at Arms
Weird 80's Vespas & Cool Vintage Lambrettas
Joined: 21 Oct 2005
Posts: 7300
Location: The state of insanity, SoCal
Wed Jan 22, 2014 8:36 pm quote
the sealant on the head is hylomar, on the base gasket it was hi-tack (p-tex 99GA)

sorry about the loctite on everything...

that cross is done for sure, how to the flats on the gears look?

harbor freight sells a gear puller set #30305 that will separate the bearing from the crank, just be careful with it-- leave the nut on fly side threads so they don't get boogered and watch the seal surface. also, heat. lots of heat.

freeze the new bearings and heat the cases and they'll nearly drop in add a few love taps from a hammer using the old bearing and you should be golden.

have fun putting the detent spring and balls back into axle!
(pro tip- zip lock baggie, bic pen and beer)

-g
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Wed Jan 22, 2014 11:06 pm quote
Greasy!! I have done the ball thing with my Lambretta, I know the plastic bag trick . I ordered the tool for this one to try it out (the 2 bar thing from Scooter West).

Thanks for the sealant info. I like Hylomar and I'll follow your lead on that and the base gasket then.

I think the gears are serviceable. I see some chips on 4th, but they are at the edge and small. I see the edge looks sort of beveled but it looks like that is intentional.


IMG_0275 by john.headley, on Flickr

IMG_0276 by john.headley, on Flickr

IMG_0277 by john.headley, on Flickr

IMG_0278 by john.headley, on Flickr

Today's question:
Is this gear tree going to work with my standard gears?
http://www.sip-scootershop.com/en/products/input+shaft+assembly+211814_40442400
I think I have the right one, it was suggested in my previous post on gearing. I just want short 4th, keeping all my loose gears and clutch basket stock.
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Thu Jan 23, 2014 7:01 pm quote
Cleaned my cases today. Nice to have access to a parts washer. My parts orders are 2 of 3 now. Just have to get my Hodgespeed in once the quote comes back with the bearing I added. No one had the fly side axle bearing in stock, so it comes from SIP along with the DRT runner tree and a Polini clutch spring as insurance if I end up with any slipping issues. I think I can get away with stock though, given the mildness of the tune. Whatever I've missed I can grab from Motorsports when I take my stator for rewiring. Since they had free shipping for orders over $100, I had them ship a bunch of stuff to me to save me the trip down there.


IMG_0280 by john.headley, on Flickr
Molto Verboso
Joined: 24 Jan 2008
Posts: 1909
Location: Santa Margarita,Ca.
Thu Jan 23, 2014 7:16 pm quote
Make sure you get the right cross as there are 3 variations
Sergeant at Arms
Weird 80's Vespas & Cool Vintage Lambrettas
Joined: 21 Oct 2005
Posts: 7300
Location: The state of insanity, SoCal
Thu Jan 23, 2014 7:19 pm quote
it seems like that tree works with standard gears so i'm guessing you should be fine?

as for the gears, i can't really say. it's nearly impossible to judge them via pix online. i mean, if they're okay or passable that is. if they're wasted you can usually tell.

i'd take them down when you have the stator rewired and have max or one of the guys eyeball them in person and make a call from there.

oh, and i generally only use hylomar for the head, but you can use it pretty much anywhere and it'll be okay.

best,
-greasy
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Thu Jan 23, 2014 8:04 pm quote
On the cross, I ordered for VMA2, but will compare when it arrives, just in case.

Greasy I hear you on the gears. The teeth all look great, it's only the corner of the flats on 4th where I have any question. I may take your suggestion and have Max have a look at it.

Thanks everyone.
Mr. Clean
P,SUPER,V90, 50 Special
Joined: 27 Jul 2010
Posts: 10207
Location: This is't my locker!
Thu Jan 23, 2014 9:32 pm quote
If you haven't seen this over there.. it's good info.. especially checking the cross by pulling the cross up and setting it down on the top edge of the gear... better with pics so:

http://vespasmallframeforum.proboards.com/thread/10843/gearbox-rebuild


... and the runner tree is great.. I'm using it w/ the stock gears and the transitions from 3 to 4 is really nice.. not a big jump at all... I think you'll like it.
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Fri Jan 24, 2014 8:11 am quote
Brilliant link Vader thanks a ton. I am glad you like yours, I paid up for mine last night .
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Mon Jan 27, 2014 10:29 pm quote
3 bearings in using the excellent SIP bearing drift that Mr. J loaned me.


IMG_0294 by john.headley, on Flickr
Addicted
'77 ET3
Joined: 05 Mar 2013
Posts: 564
Location: OC
Mon Jan 27, 2014 10:34 pm quote
Good stuff! Are you going to replace the flyside bearing?
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Mon Jan 27, 2014 11:02 pm quote
mr.j wrote:
Good stuff! Are you going to replace the flyside bearing?
Yes, Dan says he has the split bearing puller, I'll take my crank over there to remove the old one and install the new race. I'll use the oven to get the old race and drive axle bearings out of the fly side and pop in the new stuff.

My new fly side crank bearing is reversed from the one I have. The roller part will go in the case and the race on the crank. I won't get the small drive axle bearing until my Hodgespeed order arrives but in the meantime I will get the gearbox shimmed and see what I have to order so that sits right.
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Tue Jan 28, 2014 10:24 pm quote
Last 2 bearings out of the case with aid of the BBQ.


IMG_0295 by john.headley, on Flickr

Still need the bearing off the crankshaft, but I have a friend with the right tools willing to help on that, so it waits for now.

I suppose to insert these bearings I'll probably want to heat it in a similar fashion to make it easier.
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Sat Feb 01, 2014 5:56 pm quote
Got a new 2nd and 3rd gear, measured the shim gap on the loose gear stack. 2 new first oversize shims are in order, looks like.


IMG_0296 by john.headley, on Flickr
Mr. Clean
P,SUPER,V90, 50 Special
Joined: 27 Jul 2010
Posts: 10207
Location: This is't my locker!
Sat Feb 01, 2014 9:09 pm quote
sdjohn wrote:
Got a new 2nd and 3rd gear, measured the shim gap on the loose gear stack. 2 new first oversize shims are in order, looks like.


IMG_0296 by john.headley, on Flickr
hard to read for my bad eyes.. what's your space now?
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Sat Feb 01, 2014 9:43 pm quote
0.53mm, spec says 0.15 to 0.4 mm in my service manual. First oversize are 1.1 instead of 1.0, will take me to 0.33 or so, in the range.

I could grab a second also to have an option to get lower. If they are like Lambrettas you want them shimmed right for sure.
Enthusiast
LI's and a Jet
Joined: 04 Apr 2012
Posts: 76
Location: Petaluma, CA
Sat Feb 01, 2014 9:46 pm quote
Is this the bike you picked up from mark? Keep up the good fight.
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Sat Feb 01, 2014 9:48 pm quote
Yes sir, Derek! Thanks, it looks like I've dived in all the way but it'll be worth it in the end.
Mr. Clean
P,SUPER,V90, 50 Special
Joined: 27 Jul 2010
Posts: 10207
Location: This is't my locker!
Mon Feb 03, 2014 6:09 pm quote
sdjohn wrote:
0.53mm, spec says 0.15 to 0.4 mm in my service manual. First oversize are 1.1 instead of 1.0, will take me to 0.33 or so, in the range.

I could grab a second also to have an option to get lower. If they are like Lambrettas you want them shimmed right for sure.
IIWY I'd shoot for the .15 range.. you'll like tighter better than looser!
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Tue Feb 04, 2014 7:05 am quote
Thanks Vader I'll go for a second and a first, I think, will get it tighter.

Last night I cleaned up the edges of the clutch basket with a file and installed it, the circlip, the dished washer, and the spring. Reassembly has begun!
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Tue Feb 04, 2014 2:10 pm quote
Picked up a 1st, 2nd, and 3rd at Motorsports, along with my rewired stator, will try shimming it in tonight. I think it will be a 1st and a 3rd for the win.
Molto Verboso
Joined: 24 Jan 2008
Posts: 1909
Location: Santa Margarita,Ca.
Tue Feb 04, 2014 7:20 pm quote
Hope you've read this John .
http://vespasmallframeforum.proboards.com/thread/10843/gearbox-rebuild
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Tue Feb 04, 2014 8:05 pm quote
So I grabbed my handy selector ball tool from Motorsports and put it to use tonight. These bad boys make installing the cruciform dead easy.


IMG_0306 by john.headley, on Flickr

They have little dimples for the balls and you just slide them back as you slide on the cross.


IMG_0304 by john.headley, on Flickr

With the first oversize and third oversize shim, I'm right at the bottom end of the tolerance band.


IMG_0307 by john.headley, on Flickr

I followed the link and used the process to make sure my gear selections were good and that I had the proper false neutral between each gear without any double selections. The photo series on proper orientation is also sweet to double check your orientations as well.

I had both a standard selector spring and an uprated. I saw how beefy the uprated was and opted for standard. I figure since I've replaced the 2nd and 3rd loose gears, the cruciform, the spring, the balls, and the gear tree, I should be able to run a standard spring. However, I still have another day or so until I put this in, so if I'm making a mistake, speak up!!!! A lot of Lambretta owners rue the decision for the beefier spring, so I'm leery.
Ossessionato
73 Rally, 74 Rally, 76 ET3, 80 P200, 63 Li125, 65 Li225 Silver Special, 86 Elite 80, 2015 HD Road Glide Special, 2011 Ural Tourist
Joined: 18 Jan 2012
Posts: 3305
Location: Oceanside/ SF
Tue Feb 04, 2014 9:55 pm quote
I put the beefier spring in that Allstate. Shifting is a bitch! Go standard.
Molto Verboso
Joined: 24 Jan 2008
Posts: 1909
Location: Santa Margarita,Ca.
Tue Feb 04, 2014 10:08 pm quote
I use a stiffer spring. I'm hoping over time shifting become easier.
Sergeant at Arms
Weird 80's Vespas & Cool Vintage Lambrettas
Joined: 21 Oct 2005
Posts: 7300
Location: The state of insanity, SoCal
Tue Feb 04, 2014 11:35 pm quote
i run three balls instead of two...

it'll run a shit gears and a wasted cross tighter than a buck-tooth prom date!

cables and wrist pays for it, though.

your tune isn't excessive, i'd go stock.

-g
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Wed Feb 05, 2014 8:04 am quote
Right on guys, stock it is then.
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Wed Feb 05, 2014 8:07 pm quote
OK so I got a friend to measure up that ET3 kit I've been pushing for sale. 0.001" clearance piston to bore. That's what I thought.

I'll either have to figure out how to use that hone I bought a long time ago or take it to a machinist. That's crazy tight.
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Sat Feb 08, 2014 9:31 pm quote
Old bearing off, new one on, thanks Dan!

DRT Runner shipped, not long now.

image.jpg

Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Tue Feb 11, 2014 9:15 pm quote
Bit of work today.

On with the backing plate temporarily to seat the drive axle.

image by john.headley, on Flickr


Use a socket over the end of the axle so you don't bungle the part that goes into the bearing while seating it.


image by john.headley, on Flickr

Make sure you seated all the way.


image by john.headley, on Flickr

I did this with gears off the axle because I don't have my kickstart gear yet and I figured out that I wouldn't be able to seat it with the gears in the way.

Now a new clutch side seal.


image by john.headley, on Flickr

And install the crank and the primary gear with new woodruff and lock washer. Hand threaded the nut, will torque to spec later, once more stuff is together.


image by john.headley, on Flickr

Also today:
-remove remaining intake and cylinder head studs
-clean gasket faces

Waiting on:
-kickstart gear
-DRT short 4th tree
-surprise

These should arrive before the end of the week.
Ossessionato
1 Empty Garage Space, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 4021
Location: San Diego, CA
Thu Feb 13, 2014 7:51 pm quote
Got half of my goodies today. Among the haul was this baby:

image by john.headley, on Flickr

I know it isn't as sexy as a Polini but I gotta tell you I'm already happy I did it vs. the ET3 kit. Piston to bore is 0.003" (good), and the ring gap is 0.008" (also good). The ports look pretty clean and overall it looks like a nice bit of kit. I think it will do what I'm looking for, and I didn't have to wait for it to arrive from Germany.

Also got my kickstart gear. Still waiting on the DRT tree and axle bearing.....

If anyone wants my ET3 kit or the Primavera barrel and piston that came off, send me a PM. I'm talking cheap here, but I'll keep one of the two as a spare.
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