It won't start, please help!

[smoke]

Hi folkes,

Well I was tinkering with the vespa and now it wont start.

Hoping someone might be able to help me out?
Here's as much info as I can think of which may be important.

Its a PKXL with what I think is a a post 1970 large frame engine (thanks to scooterhelp.com for that one!

The scoot doesn't get run much, and it always takes a lot of kicks to get it started.

I decided it may be because of a old spark plug that needed changing, so I started to try and change it. While I was there I foolishly started fiddling with other screws - see image:



After fiddling with one I noticed that when ever I gave the engine a kick the engine was making a 'phutty' noise like air escaping, also some black liquid was leaking, so tightened that them all back up! one of them had a split bolt on so wouldn't tighten up fully (should this be a split bolt?).

Anyway I then changed the spark plug but it wont start now, it doesn't even get close to starting, just kicks over and nothing.

Any clues what could be wrong? Hope someone can help!

I've put some more pictures here in case they help!

[afscmik]

You have loosened your cylinder head mate and probably the barrel as well take it right off and put new gaskets in. then tighten it back up properly. the split nut I assume you mean the large one near the spark plug in your picture? That is what holds your cylynder cowl on. It must have the cowl on to cool the engine properly. Has it ever run. that engine doesnt look like it fits very well. It looks to be rubbing on the frame. the suspension will be impeded if it is.



is this a wind up?

[smoke]

When you say, is this a wind up? Do you mean, am I taking the p*sh?

If so, no.

Sorry If I'm being dim, trying to work things out but I am a complete beginner and I'm trying to teach it all to myself, gotta start somewhere!

Yes it has run, it was running ok but has been deteriorating for a while. By the looks of the spark plug I think the fuel air mixture is too rich, can anyone tell me what I should do to alter this?

Nope the motor doesn't fit very well in the frame, it rubs on the side panel. This is because the person who owned it before me put a large frame engine in a small frame scooter, badly.

But not too fussed cause I have only got it to try and learn a bit about how it all works before I try my hand at a good'un.

Oh and thanks a lot for your help, much appreciated! I think I can get most of the details on how to do what you have suggested from scooterhelp.com, but if anyone has any further guidance on how to tighten it back up properly that would be wicked!

Cheers,

s

[Rudi]

hi
you dont really have to open it up, the head doesn't have a gasket (its metal on metal sealing) and the base is aluminum , so just tighten the nuts once again. do it in an order described here:
www.vespamaintenance.com/engine/decoke/index.html

[smoke]

Thanks a lot for your help, will let you know the results!

[afscmik]

Hi smoke sorry mate, didnt mean to sound condescending. yeah I forgot the vespa doesnt have a gasket , was thinking about Lambretta. so you should be able to just tighten up the bolts diagonally put the cowl on though especially if the side panels are on. My Mrs has a PK with the right engine and it gets very hot under there with the cowl on. again I'm not sure about the rubbing. It cant help if the suspension cant travel freely. good luck though mate. As for the carb? sounds like this could be your problem. I struggle with jetting and mixtures but if it was ok and now it isnt without touching it I think you may have disturbed something and its pulling more air in than it was previously.

[Smallframe]

Its a pk with a px motor in it. Whip the carb off and check your jetting a la px 125 (?) , clean carb thoroughly, leave air screw at 1.5 turns initially. Torque head down, check exhaust ain't rotten. Chjeck carb airbox is tightened down sufficiently with a gasket in place.

The drink a bottle of thunerbird and stare at yourself naked in front of the mirror ( it helped me !)

[smoke]

Thanks a lot people.

Everyone on here is so helpful!
WIll be borrowing a torque wrench and then following the guide from vespamaintenance.com. Think I will go ahead and de-coke the thing while I'm at it.

Thanks again, hopefully it'll be back running again soon! Otherwise might have to just go ahead with the thunderbird suggestion!

S

[hutchie]

you may also want to check that your getting a spark (remove plug reconnect supp cap let thread area of plug rest against cylinder and give it a kick , you should see spark between contacts when engine turns over ) just incase you have a bad connection onto ht. lead at the coil or the cap , but it does sound like youve loosened the head and lost compression