Modern Vespa

Hello all,

Long story short, I recently bought a project GT200 and what I thought might be a simple fix has turned into possibly needing a new engine. The previous owner hastily put the engine back together, not even bothering to replace gaskets or checking timing or anything like that. Up until today I was scratching my head as to why the engine was apart in the first place and I think I finally found it.

This first imagine is looking down the cam chain tunnel. It appears to have some JB Weld smeared in this area. The second imagine is with the case halves split with my finger in the hole I'm trying to point out. Picture 3 is a side view. I'm wondering if that hole is supposed to be there at all? The opening looks too rough to be intentional. Can someone tell me what this is supposed to look like?

Thanks,

Brandon

Wow. It looks like someone rebuilt it with a hammer and a chisel.
Long story short, you will be better off buying a complete used engine, because if they put it together and ran it like that, who knows what other nontraditional and unique skills, materials and techniques were utilized in reassembling the engine.
The Crankcase halves, which you need, will run more than the cost of a used engine.
Patience and diligence will find you an engine in the 500-700 range on ebay.

yeah... that's not supposed to be like that.

like motovista said, seeing what's been done would make me think that there's more bad juju hiding in there.

if you need cases or a complete motor hit me up

You mean like this unique skill? 🤣

Well I guess I'm looking for a gt200 motor now lol. Let me know what you have.

I'll shoot you a PM

Is that the silver one from the guy in Washington Park? If so, I looked at that scooter.

Negative. Black out of Longmont, CO

I have a GT and a few months ago it looked like my engine was toasted. Since the bike was scratched on both sides and as a result has a salvage title it was not cost effective to replace the engine so I was planning to part it out.

I managed to get the engine going with a cheap trick, at least for now.

I checked prices for some of the parts and because most parts are not readily available they bring good prices. You may be able to defray some of the cost by selling things like the carb, head, piston/cylinder/connecting rod assembly and I, person's would be interested in the crankshaft if you decide to do that.

Good luck.

Hey Red,

Yes the crankshaft is in good shape on this bike. I'm thinking it is more cost effective for me to buy a whole new engine which then leaves me with a bunch of extra parts. I'll keep you in mind down the road depending on what transpires here.

WHAT IN FRESH HELL IS THAT??

I was thinking along the lines so AvE, the YouTuber:


Release the schmoo!

I appreciate it.

I look this screenshot at 6:41 in Robots video (link below). I'm 99% sure this hole is supposed to be there. I agree the JB weld is weird, but I also don't think it's helping or hurting anything. I'm just really surprised how rough the casting is.

I know I'm going to be hard pressed to find anyone that's going to say "yeah, I'd run that" lol. All this I guess to say I'm going to run it and see what happens. I'm maybe $600 into this entire project including the cost of the scooter, so to spend that on an engine just because of a little JB weld in a non-critical area doesn't seem worth it. I'll report back in 6 months to let you know how it goes.

Thanks all for your responses!

&list=WL&index=1&t=2067s

good lord. some people should have their tools taken away. this also reinforces my belief that you should have to pass some kind of a test to get a license for use of RTV and other sealants.

anyway, make sure you get ALL of that cleaned up and out of the oil galleys-- especially the oil squirter for the piston.

that hole is supposed to be there, but it looks a little wallowed out. however I don't think that's the intended application of the JB, I think it was lower where the chain guide sits (magenta circle). but the green square shows where maybe a piece was knocked off and they tried to glue it back.

either way, those cases look hammered and JB inside of case throws red flags for me.

They say a picture paints a thousand words, I can't find one

If you attempt the rebuild, remember, the impossible takes time, miracles take a lot longer good luck

quote="brandonh98"]You mean like this unique skill? 🤣[/quote]

here's a shot off a set of cases I have kicking around. while the casting is obviously not well finished, it's not near as rough.





so draw your own conclusions, I guess.

I appreciate you taking these pictures. I think I'm going to take my chances with these. Worst case scenario I'm back to buying a whole new engine lol.

I wouldn't worry so much about the holes but mainly for the crank's end bearings that look rough in the pic. Plus the rust which suggests that water was in the engine at some point…

word. you know where to find me if you wind up needing a whole engine, I'll throw it back up on the shelf for ya.

You have a really good eye! I too am a little concerned about that. Here is a closer image. I'll be the first to admit that it LOOKS terrible, but to touch I actually can't catch a fingernail on any of that. At what point is it considered toast?

Yes, there was definitely water inside this engine.