Author Topic: SOLYTO moteur  (Read 1646 times)


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SOLYTO moteur
« on: June 14, 2013, 12:19:41 PM »
Hello again everybody

Firstly, thank you for all the follow-up on my last thread, which morphed into a discussion of Inters - what wonderful cars!  Jean-Do, I was particularly pleased to see you joining in - I've found lots of stuff on the web posted by you, and really appreciate your knowledge and willingness to share it.  I look forward to meeting you soon

New thread:  Engine.  I have managed to extract the motor from my Solyto, only to discover that the cylinder head was very loose, and that the engine has been filled with seawater at some time.  It has had a hard life before that, as the range of missing studs, larger-than-standard studs, scored surfaces and so forth reveals. 

I soaked it in a admixture of acetone and ATF, but that didn't seam to achieve much (although it has worked well for me before): the piston was seized solid in the bore, the crankshaft is locked solid and the big end seized.  Removing the head was easy enough, and the barrel could be unbolted, but would barely move. Undoing the crankcase bolts made no difference at all;  the crankcase halves remained firmly locked together.

In the end I took it to the local Piaggio agent here in Dubai, where modern Vespas and the like are serviced, and the odd bike restored.  My instructions were clear:  "clean it in your parts washer, and try to dismantle it using whatever special tools and techniques you can, but please don't break anything.  I'd rather get it back still in one frozen lump than have it damaged."  A couple of days later I received a call to tell me that they'd managed to get the barrel off, and split the crankcase.  I wet to collect it, and found the piston in two parts, one half of the crancase broken and the other half still firmly fixed to the crank, which is still seized rigid.  They hadn't cleaned it before beginning either, although in retrospect that's fairly academic given the other issues.

In the meantime, I've been trying to recognise what it is, and after trawling the web I've concluded it's an Ultima V4-2.  The bore is around 52mm and the stroke 58mm, which is around 125cc if I've done my sums right, which would tend to support this theory.  The seawater has caused lots of rust as you can see:  I think the corrosion on the outer face of the bearing races has effectively locked them into the aluminium housings, and it clearly hasn't done the big end any good.  Anyway, folks, my questions are these:

Can anyone confirm that what I'm looking at is an Ultima V4-2?
Are such engines still to be found?
Are spares - pistons, big-end bearings, gaskets - available?
Does anyone have half one they'd like to sell?

On a related thread:
Can anyone advise how to separate the parts?  (This is possibly a thread in itself, or could be gathered into one later perhaps). 

As I said, I've had great success with ATF/Acetone mix as a penetrating oil, and would strongly recommend it.  However, in this case I'm up against a bigger cliff.  I look forward to hearing all your brilliant suggestions.

Enjoy the pics

Best wishes


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Re: SOLYTO moteur
« Reply #1 on: June 14, 2013, 12:22:16 PM »
Here are couple of pics of the piston.  It has a large port in the side which I failed to show in the pic - sorry.

Can pistons be repaired? 

Cheers, Will

steven mandell

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Re: SOLYTO moteur
« Reply #2 on: June 14, 2013, 01:35:48 PM »
I know it is akin to nailing the barn door shut after the horses got away.   But you asked- so my suggestion would have been to bring it to a machine shop with a good reputation for being careful and creative after about a week long soak in the penetrating elixir of your own choice.
If that elixir included acetone, I would give it a post soak in a penetrating oil with lessor percentage of volatiles, so that a lubricacous film would remain on the parts at the time of their being mounted in clever jigs on a big press.