People Gti 125 won't start

[scooterfan]

Thank you for your reply



Yes, there's another way to tell the right position. There are two holes on the camshaft that must be aligned with the engine head surface, but it's really difficult to tell since you don't have the right visual angle. Instead, I relied on the marks on the flywheel but I have this doubt of which one of the two on the flywheel must be aligned with the one on the crankcase cover (as in the picture). In doubt, I put it in the middle of the two but I still remain with the doubt 

If you prefer to do the valve clearance settings this way you are at the brink of success !

It’s not difficult at all !  When the two holes are lining up with the cranckcase cover - just have a close look at the position of the camshaft lobes. If the lobes are facing forward ( towards the front wheel ) it meanns the piston in NOT in “TDC” position, (in theory) and you should NOT try to do any valve clearance adjustments.

If the two holes are lining up with  with the cranckcase cover and the two camshaft lobes are facing the rear wheel - BINGO ! The piston will be at TDC position and you can do the valve clearance settings !

[CROSSBOLT]

If you prefer to do the valve clearance settings this way you are at the brink of success !

It’s not difficult at all !  When the two holes are lining up with the cranckcase cover - just have a close look at the position of the camshaft lobes. If the lobes are facing forward ( towards the front wheel ) it meanns the piston in NOT in “TDC” position, (in theory) and you should NOT try to do any valve clearance adjustments.

If the two holes are lining up with  with the cranckcase cover and the two camshaft lobes are facing the rear wheel - BINGO ! The piston will be at TDC position and you can do the valve clearance settings !

Simply a genius way of doing this!

[Faber32]

Thank you :-) Unfortunately I have an update. After replacing the spark plug it started. But next day same exact problem. I have done many attempts and I have understood that the problem is a wet spark plug. If it doesn't start, I extract the spark plug, I clean it with brake cleaner and get it dry and it starts perfectly at first attempt. Do you know what could be the problem?

The only symptom I have running is a lack of power in acceleration from 20 mph to 35 mph, but I think this is due to a non-genuine belt I replaced 2 years ago (it started lacking of acceleration just after replacing the belt).

[Ruffus]

@Faber32,
fuel there is for a start to check better than none.
Is it fuel at the sparkplug or oil?
Does the scoot smoke bluish from its muffler after its warmed up a bit?
 Could mean valves still out of order or piston rings little bit worn out.
Sparkplug gap too small?
Really the right sparkplug?
Pls check up on all again.

[Faber32]

The scooter has only 15k miles. The spark plugs I extracted after 3k miles were oily at the tip and black, too much in my opinion. But now the spark plug gets wet in a day or so. And it smell strongly of gasoline.
It smokes a little white/blueish, but oil consumption is really really low, quite none. Spark plug is a CR7E as recommended. Gap is fine in specs but I discovered I did the last 4k miles with too much gap (0.8 instead of 0.6-0.7). Could I have ruined the engine?

[CROSSBOLT]

The scooter has only 15k miles. The spark plugs I extracted after 3k miles were oily at the tip and black, too much in my opinion. But now the spark plug gets wet in a day or so. And it smell strongly of gasoline.
It smokes a little white/blueish, but oil consumption is really really low, quite none. Spark plug is a CR7E as recommended. Gap is fine in specs but I discovered I did the last 4k miles with too much gap (0.8 instead of 0.6-0.7). Could I have ruined the engine?

White/bluish smoke is oil. That generally means either too much oil in the crankcase or bad oil control ring(s).

[Faber32]

Thank you for your reply!

But supposing that compression is not good or that there are major issues in the engine, why removing the spark plug, drying it and reinserting it, it starts at first attempt perfectly as before? Today I drove for 20 miles with no issues. If there's a lack of compression it should not start at all. Am I right?

[Ruffus]

@Faber32,
this wider sparkplug gap does not have any significant side-effect and harmful doing on your motor.
Your scoot needs, to burn off this oily stuff from your sparkplug, a few miles until its heated up enough to do a selfcleaning.
 So, If you start your scoot and just let it idle, the sparkplug will look darkish oily.
But the fuel has to come from somewhere?
If it would be a carb-motor, I would say it's the level valve which is faulty.
On your injection is a fuel line too, which leads to your injector,...
Look around there, where the fuel is getting to.
There are two idle-regulation screws, check up on them but do NOT losen this two hex-bolts which fix your ECU.
Thumb rule Compression Test::
-sparkplug out and away
-GLOVED finger on/into sparkplug thread
-ignition on and start
-GLOVED finger should be airblowed away from ...
-NO blowing away, compression tester borrowed from somewhere and...

[Faber32]

Thank you again, really :-) it's an interesting diagnosis and I'd like to try to solve it before going to the mechanic.

In my People ignition is electronic, no carburator I think. Yesterday I cranked the engine without spark plug and it blew out air and gasoline strong. Today, thinking that it was only a case of flooded engine I made 20 miles at high rpms trying to burn all gasoline but then after 6 hours it didn't start again. Spark plug gets wet when sitting for hours. At this point I am thinking about a leaking injector. It could explain the issue.

For idle rpms I think they're ok, engine sounds as always at idle and it's ecu controlled.

I'll check if the injector leaks. Is it enough to remove it and check if it drops gasoline when engine is off?

[Ruffus]

@Fabelr32,
an injector is principally nothing else than a magnetic valve which is opened against a spring by an electric pulse at the right moment.
So, to check its function, seat and underbay off
- yes take injector out, DONT take the fuel line off
- have a good view on it and put it in a transparent cup
- we'll see what happens.

[Faber32]

@Ruffus: thanks so much for your reply :-)

Scooter has been sitting for the night now. Today I'm gonna remove the injector (letting the fuel line attached to it), put it in a cup and see if in a few hours it makes the drop of gasoline. If so, I've found the issue. It should not leak at all with ignition on and off, right?

Then I'll crank the engine to see if it sprays fine and strong.

Curiosity: I have an endoscope. If I put it inside the spark plug hole should I see the combustion chamber flooded with gas? Or should I put it in the injector hole?

I hope I don't have already hydrolocked the engine.

[Ruffus]

Endoscope is most probably one of the better ways to find something out. Sparkplug hole or injection port.
NO your injector should NOT drip with inition ON and without cranking.
No, if your motor would have been "hydrolocked" , it would not have started that easily. Fluid is not compressable in this way.
One more thought:
-when your injector is out and in a container, switch ignition on (you should hear the fuel pumm running for about 10 secs) and watch whether you injector is dripping. IT SHOULD NOT, only with ignition on and pump running.
If its drips, some grain is in your injector nozzle.

[Faber32]

I have put the endoscope in the plug hole. This is what I saw with cold engine after night.

Unfortunately I forgot to take with me the mirror at the end of the endoscope to see all around, but I'll do pics with the mirror later.
This is what I found. You can see some gas drops on the cylinder wall and I just noticed a strange glare on the right side (the downward one which for gravity should collect gasoline) looking at the pics.

I'll investigate more, but to me it doesn't seem a flooded engine. I also removed injector, try to turn ignition on but I didn't see any dripping waiting for 2-3 minutes. Probably hours are required to see a drop. I have to do all these attempts but I'm about to give up and go to the dealer 

Ah, today it started again perfectly after drying the spark plug. It's absolutely a flooded plug issue. Now I'm 99% sure

[Faber32]

second pic: if you look closely it seems on the right side that there's a puddle of gasoline. I'll do further inspections in the next 8 hours

[Faber32]

Removing the air filter (because I saw leakage signs under it) I found this: in my opinion are signs of gasoline leaking from the air intake pipe.