Modern Vespa

Going to put my hands up in the air and admit a bit of wrenching blunders have taken place.

Well you probably remember that ny bike had a loss in performance?

Well, my dipstick and I had a little meeting and have concluded it has half gone... Well from the max level(a little over) to about just under halfway on the dipstick.

I think I may have over filled and broken a ring or two... A tapping sound is apparent from the cylinder head at idle on the stand and over the past month or so its getting louder.

Time to pull the head off I think but one issue, this is never been attempted by myself and am worried if I will be up to it.

Is there a guide around on how to get the head off to check the rings? Hoping the engine can stay put in the bike!

Nope.

Workshop Manuals

Firstly - never bother to fill to the max mark on the dipstick. Halfway is fine. Your oil has probably mostly gone into the air filter.

The tapping noise is probably just the valves needing adjusting. You can do this with the engine in situ, but it helps to remove the rear shock and lower it for better access.

Before you go making a scooter into a pile of parts, read a bit on diagnostics, and what you should do before taking anything apart.

You ran a little low on oil... it's not the end of the world (yet). To be sure things are ok, do the following:

1) Do an oil change, drain the old stuff, replace the filter and refill with exactly the right amount of oil.

2) Do a tune up while you're here... new plug and air filter.

3) After everything is put together, go for a short ride

4) IMPORTANT: Do a compression test on the engine while it's warm. This will let you know if you've knackered a ring or a valve.

If the compression test turns up with good results (do the test with a wide open throttle), then just adjust the valves and continue riding.

Hoping its escaped to my air box! The oil vanished very quickly with bo trace in my little bubbles.

Though, I am overdue for a valve adjustment, so the valve shoes tapping sounds right on though.

Got a good week or so to have a poke anyway. I know there's gauges about in the garage, assuming feeler gauges are all standard if you have the full set.

Made this link as the performance loss happend not ling at all after the oil and air filter change/clean. I noticed increased performance for the first few 100 miles and then bam.

I do realise I went down the wrong route getting it dyno'd as this just showed I was running far to rush which also adds to the puzzle. But made me think down an electrical issue.

This also sounds stupid, but I swear I've lost compression, used to be able to hear my compression on starting and it would always fire up on the first ignition stroke. Now it feels... I don't know, its just like its a little wet... Not as strong as before anyway just turning it over. Was very noticeable with the om tuning exhaust, just to get a strong pah pah pah but it turned into more off a "puh" sound... Like a softer compression. Wow that was hard to describe.

Anyhow, gonna adjust the valves this week hopefully! Will try and follow the workshop manual the best I can!

Hmmm... JimC (sorry for the caps) has a point.... since I don't have a dipstick (stop laughing now)... since my SCOOTER doesn't have a dipstick... are you talking about being seriously low on oil, or just between the max and min lines?

If you're between the MAX and MIN lines on a dipstick, your oil level is fine. Best not to let it get below the MIN, but going above the MAX line can result in just as many problems also.

It was slightly over the max level, then it dropped to about halfway between the nin and max level. At the sane time the issues slowly started to come about.

The hole on my o2 sensor made me look elsewhere till now!

It hasn't seemed to have dropped much more than that since. I will have a look again tomorrow on the old weekly go around.

Woops, didn't spot your previous post Larry must of been typing st the sane time.

Doubled checked the air box and its fine,
New plug cant go a miss though but its only been in since march!

I do have a compression tester... No idea how to use it though.

Ah, grasshopper, possession of a tool with no knowledge of its use is like giving an elephant a computer.... fun thing to throw around, but eventually it's either a weight or an object of art.

These interwebs must have a compression test video on here somewhere.....



https://www.youtube.com/watch?v=l_RMl5IIenA

There surely should be! Pretty sure I'm meant to have some adaptors for it.. Which I do not have! Or discovered...

I'm in the strange situation where the garage wasn't mine untill we inherited it and its full to the brim of old vw parts and tools... I basically just have to look.

So far i have a full torque key set, two sets of torque wrenches, all sizes of spanners in various different lengths and god knows what else. But all proving to be very useful. Found a parts cleaning kit the other day, well more of a parts bath to clean the engine components needless to say I don't have to buy any tools for a while!

And after watching the video that seems very straight forward...

Just need an adaptor I think! I have a sykes-pickavant compression tester, has an odd bottom though so I hope it will still work for the scoot.

Just bring the tester and your spark plug to an auto parts store and they can probably point you in the right direction. Some parts stores lend out compression testers for free or a nominal fee.

I shall hunt around tomorrow if that's the case! Ahh the pains of trying to get to that spark -plug. Should of checked it by now really rather than just assuming its still okay but its so awkward to get too! Ahh well, needs must.

One thing I noticed, on the tutorial it is mentioned to get the true psi reading you have to kick start rather than use the electric start, what do I do if I only have an electric starter?

Thank you for the input!

Just,spin it over on starter button

You know you're a grasshopper when it takes for the ht lead to shock you to know something is wrong.

Putting this on hold and will start there.

Doing the valve lash adjustment sometime tomorrow just for good measure.

Still waiting in the lead,

Its not as complicated to swap out as it is on the gts is it? Oh well if so, will have a poke and see when it comes.

Hoping this will do the trick, orange is the best functioning colour.

http://vi.raptor.ebaydesc.com/ws/eBayISAPI.dll?ViewItemDescV4&item=361400188219&category=122303&pm=1&ds=0&t=1447938652739

Edit:

Oh damn and blast. It appears this one of for the older models. Never trust the description on ebay folks!

Can the lead unscrew from the original coil? Seeing as the coil is actually a bit pricey I'm trying bot to switch it out.

Right, got the ignition sorted out. Seems to be running with a little bit more pull which is a good thing!

Noticed something a bit concerning though, would anyone be kind enough to take a photo of the engine just under the inspection cover so you can see the rubber gasket seals? Is there meant to be space between the gasket and the engine?:') something doesn't look right but I may be just confused.

Will be hopefully doing the valves over the next few days if no more delays occur!

Cheers guys

All sorted at long last.

Turned out to be a few issues.

Valves are now with in specs, but they weren't too far off at all but this did help and finally I decided to rip apart my o2 sensor as it was still bugging me even though PADS registered it as working. One of the 4 wires had received damage from the old pm pipe pushing the shit out of it, think the copper must of split internally. So I guess it was reading that it was plugged in but it wasn't functioning correctly. Had a little fiddle to try and get a connection and then boom the revs started to adjust at idle. A then hopped on and woosh the bloody thing took off.

So even after load testing and pads saying all is good, all was not good. Sneaky bastard!

New sensor ordered and finally relieved.

Glad you got it sorted. Thanks for coming back on with what the problem was. 8)

Ahh I'm on here too much for my own good and I know this has been pretty long winded, would be pretty rubbish of me to expect help and bot to follow up. You've all been brilliant once again


Only a few more kinks to iron out. Just got to work out what's causing the whine when I let go of the throttle when the engine is hot. Sounds like a bearing is going. Well actually sounds exactly like a bearing going but trying to best bet to which one it is before stripping the thing down.

If its not to much of an issue, I'm going to leave it untill I get my new gts, even though I don't like the brand the scomadi 250 6speed looks very very appealing depending on how long they take to get it on the showroom.