2003 Stella 2t Won't Start

[kgatesman]

It just died in the intersection and the GF called in a tow.

I have spark. The compression seems very low about 60 psi. Where does compression most often fail on a Stella?

[Robbie]

60 PSI with a screw in gauge?

Meaning not guessing, right?

If low as you say, and you were just sitting at a intersection, I'd be looking for a loose head bolt or two.
If, however, it died at the intersection after you were ringing its neck prior to that, it may have broken a ring or began to seize, scoring the bore/piston/rings.

Rob

[kgatesman]

She was sitting there idling and it just died. The gauge is pretty new, a screw in type and measures about 118 on my P200.

Thanks for the tip on the headbolts, it seems odd the pistons or rings would fail when it was idling.

The P200 head is torqued at 12.30-15.91 lb ft, is it the same for a Stella?

[Robbie]

She was sitting there idling and it just died. The gauge is pretty new, a screw in type and measures about 118 on my P200.

Thanks for the tip on the headbolts, it seems odd the pistons or rings would fail when it was idling.

The P200 head is torqued at 12.30-15.91 lb ft, is it the same for a Stella?

Yes.......

Rob

[kgatesman]

Thanks Robbie, fingers crossed.

[viney266]

Do the comp. check again. Then if its still 60, throw in a teaspoon or 2 of motor oil and try again. The oil will seal the ring for a few seconds and IF the compression jumps way up, its top-end time. If it stays almost the same, keep looking....Yeah, its shadetree, but it works

[kgatesman]

I took the head off, decoked, changed the plug. Put it back together with a little red RTV for good measure. Torqued the head near maximum (noted above).

Compression isn't up much, still around 60. It will start now but runs really rough.

I squirted some 2T in the cylinder head as suggested, and compression jumped to about 85.

Thanks for the tips guys. A new top end seems to be in order.

Could she just get away with rings? To change the piston, rings, cylinder and head, besides the torque wrench, what special tools do I need? I don't want to mess with the crank, is the stock kit recommended?

[SYMbionic Duo]

Only special tools to replace a jug and piston would be a pair of needle nose pliers or a circle clip tool, depends on what type of clip is used on the wrist/gudgeon pin.

You will also need a file or a dremel to champfer the ports on the new jug and piston. (bevel the edges so that you don't snag a ring on the ports).

If you add a cylinder other than the stock one, you will have to rejet, so there is that.

As to what kit to get, it all depends on your riding style and pocket book. And most kits will require additional work to match the transfers on the case to the jug. (dremel time)

So what do you want out of your new Stella top end?



-duo

[Robbie]

kgatesman?

Do another compression test with the exaust system removed.
Any flow obstruction (like a carbon chunk or heavy buildup of 'mung') will cause a low reading and lousy operation.
I mention this only because you indicate the failure occured in such a strange fashion, ie, instant power loss.
Thats why a broken ring was mentioned.
Also, while the exaust is off, you can look into the port for any carbon blockage and a ring/piston look see.
The exaust side (hottest area) will show piston distress (heavy scratches from material transfer)
Since you had the head off and did not mention any sign of scoring, consider this the final step of diagnosis prior to disassembly.

Good luck,
Rob

[kgatesman]

We picked up a Pinasco kit, and have the engine ready to come off. All the cables, tubes and wires are labled. Tomorrow we drop the engine off the frame, put on the kit and start to reassemble it all. So far I am not scared.

I was pretty disappointed to find out I need to take the engine off, supposedly with a P200 you can just remove the lower shock bolt, tip the engine and pull the cylinder off. I haven't tried so I don't know first hand.

[kgatesman]

What is the deal with that spring? See how it hooks around the idle screw.... Is this right? Looks pretty cheesy to me.

[kgatesman]

Probably the work of the dude that installed the front turn signal with wood screws.

[Robbie]

What is the deal with that spring? See how it hooks around the idle screw.... Is this right? Looks pretty cheesy to me.

Good grief!

I guess someone decided to lose the damper spring on the idle speed screw and created that, uh, side pull thing.
What other weird past does this thing exibit?

Rob

[kgatesman]

I think that spring is supposed to be in the chamber that the choke slides in, can someone confirm? A carb rebuild is next! At least I've done that before.

[BuddyRaton]

I was pretty disappointed to find out I need to take the engine off, supposedly with a P200 you can just remove the lower shock bolt, tip the engine and pull the cylinder off. I haven't tried so I don't know first hand.

Why are you dropping the motor to replace the top end? Remove the two inner studs and the jug will slide right off. Insert the inner piston circlip before sliding the wrist pin in.

Don't forget to chamfer the ports

[kgatesman]

I don't follow you, I can't see how that cylinder head is getting past the fender unless I take out all four studs. There is about 1/4" of fin that extends under the fender.

I've never removed a stud. Can I do it like this guy: http://www.youtube.com/watch?v=XfUG6ImLYJ4

[kgatesman]

The Stella had a broken ring. Mystery solved. I was installing the Pinasco kit and broke one of the new ones too. That'll set the project back a week and $50. Looks like the fastest way to get on is through SIP at the moment.

What is a piston ring made out of anyways? It seems like some kind of metal, but they are brittle and flexible.

[Robbie]

The Stella had a broken ring. Mystery solved. I was installing the Pinasco kit and broke one of the new ones too. That'll set the project back a week and $50. Looks like the fastest way to get on is through SIP at the moment.

What is a piston ring made out of anyways? It seems like some kind of metal, but they are brittle and flexible.

Rings are made of Iron.
As you found out, flexible to a point.....then you find the brittle part as it snaps in two.

Hang in there,
Rob

[kgatesman]

Engine is back on, all the wires and hoses are connected, the jets are in.

The instructions are lousy. Tips to understand better: The ring has a top side and a bottom side, and you may not think there is a pin in the ring slot on the piston, but there is.

The Pinasco nuts suck. They just aren't quite right, they spun on ok, then stripped, when I removed two of the nuts, I pulled out the stud/shafts out too. Thanks to BuddyRaton for making me think about how to remove and install studs in advance.

Thanks to Robbie for sticking with me.

Tomorrow, I hook up the cables, attach muffler, top off the gear oil, check the compression and start it up. I hope.

[kgatesman]

It's running, I took it around the block and all seems good so far! Thanks for the help!

[fisher1]

It's running, I took it around the block and all seems good so far! Thanks for the help!

Hoping your running 2% 2T oil in the fuel if you took your carb off - until you're sure the auto lube is working, right?

[kgatesman]

Fisher1 you maybe on to something. We rode her a couple miles and she just died in the intersection at idle. Ran home, got the trailer, picked her up, rolled her into the garage and she started right up.

The Stella dies when way hot, but runs like a champ when cold. Is this consistent with the auto-oiler failing?

[Robbie]

Not necessarily failing......just air bound.

Remove the oil feed line at the carburetor......just pull it back off the fitting enouph to allow it to dribble some oil.
This purges the air from the line.
Re install the line.

Remove the oil cap and use it as a cup.....fill it with 2t and pour it into the fuel tank.....then top off the tank.
This will provide approximatly the 2% oil the engine requires.
At worst, the oil pump and pre-mix will provide a 4% mix ratio.....at worst, you will be at 2% till the pump finishes evacuating any air.
Since you'll be gentle with the throttle at break in this slight 'overmix' isn't a bad idea for new rings to seat anyways.
Once that fuel is almost exausted, go back to straight fuel.

Always watch for some smoke at first cold start of the day......new engine or old.
This is your proof that the oil pump is functioning as designed.

Nice meeting you guys yesterday and I will stop at Windy City this morning.......

Rob

P.S.
Drip a bit of 2t down the carb throat before starting.....this to provide some pre-lube in case the cylinder/piston/bearings have dried out of lube during your early run time.


To the readers: The Windy City stop mentioned is the final day of Slaughterhouse 19, a scooter rally, here in Chicago.....they're serving breakfast.

[kgatesman]

I premixed a tank of gas and drove around for about four miles before she died this morning. It's been setting for about half an hour and won't start yet.

[fisher1]

Remove the oil cap and use it as a cup

That's a neat tip, 2% is about 2.5 oz per gallon (128 Ozs).

But heads up that if you can do this, it means the 2T oil cap wasn't made correctly and the slot in it's side that allows the 2T tank to breathe just a bit is filled with sharf as a result of incorrect molding. Take a look at the cap's side that fits down inside the fill-tube - there should be an open slot top-to-bottom that allows minimal venting up to the base of the cap. It prevents a vacuum from building up in the 2T tank - just like a fuel tank vent blockage can cause a vacuum and fuel-starve the engine. The slot should be open, otherwise it's a complete compression fit/seal down the tube that can in the worst case eventually cause a vacuum that interferes with normal oil flow. Hopefully, there a minimal air leak somewhere else in the tank-fill tube joint to prevent this.

[kgatesman]

It seems a loose coil wire is at least half my problem. It might have been intermittent, or maybe the new head had an issue too.

Either way, I now have a guy that's going to change the crank for me, and am waiting for that to happen. I hoped to avoid this cost for some more months, but I will get some peace of mind knowing the crank isn't wobbling my new head to death.

The head and rings (I installed) were not damaged when he took the engine apart, and that was good news!

[kgatesman]

All the parts we ordered from Scooterworks have been on hold for four days. They had a power/IT problem. Our parts still have not been pulled. Meanwhile the scoot is in pieces on a buddy's garage.

In other news, "Genuine" branded parts will no longer be sold by Scooterworks via the website. You have to go to an authorized dealer. So, there, you might as well get your replacement rubber and cables from someone that sources their parts from Europe.

[Anachronism]

It's running, I took it around the block and all seems good so far! Thanks for the help!

Hoping your running 2% 2T oil in the fuel if you took your carb off - until you're sure the auto lube is working, right?

This. Very Very important. I just got my Stella Rebuilt after its second crank failure.

It turns out my break in was done solely on the 2% I was putting in the tank.

The oil pump is so low volume it will NOT self prime- I went 500 miles and it still hadn't pumped the air out.

What I did to prime it is I took a pump that I use to pump gear oil into the transmission, and use it to pump oil into the metal line that goes from the outside of the air box to the oil pump. Then I took the feed line, and held it down until oil was flowing out of the line, then connected the oil line, then put the airbox on and reinstalled the carb. Even then, it took about 100 more miles before it started working.

Whenever you undo the oil line to the pump, YOU MUST TAKE EVERY PRECAUTION TO GET ALL OF THE AIR OUT OF THAT LINE, AND YOU HAVE TO PREMIX.

DO NOT STOP PREMIXING UNTIL YOU HAVE VERIFIED AUTOLUBE IS WORKING- verify by sticking a Q-tip down the carb with the engine running. Cover the oil injection hold in the carb through with the Q-tip for a few second and verify that it has oil on it.

I can exceptionally close to running my engine dry because I didn't prime the autolube correctly.

[Anachronism]

A

In other news, "Genuine" branded parts will no longer be sold by Scooterworks via the website. You have to go to an authorized dealer. So, there, you might as well get your replacement rubber and cables from someone that sources their parts from Europe.

Don't buy rubber scooter parts from India. I've never seen such terrible quality rubber.

[Anachronism]

Either way, I now have a guy that's going to change the crank for me

The stock cranks are just terrible. It seems the 2003-2004 cranks were a little bit better than the rest, but the failure rate is really, really high compared to Vespa/italian parts.

The first thing I though when reading your first post was "that sounds like a dead crank."

At this point, my advice to pretty much anybody running a stock Stella crank is to change it before it fails and messes up the rest of the engine.

After two crank failures (On a Bike with 3000 miles!!!) my cases are badly chewed up. Good thing the LML cases are reeds, because my cases would not seal if it was rotary.

When my crank was replaced under warranty at 1800 miles, my biggest regret was not paying to have an aftermarket non-LML crank thrown in. I asked the shop about it and was told at the time in 2009 that my failure was a "freak" occurrence, and the stock cranks in the 2009's had fixed the issue. I would love to know who sold them the bad crack they were on at the time.

[kgatesman]

A

In other news, "Genuine" branded parts will no longer be sold by Scooterworks via the website. You have to go to an authorized dealer. So, there, you might as well get your replacement rubber and cables from someone that sources their parts from Europe.

Don't buy rubber scooter parts from India. I've never seen such terrible quality rubber.

That was kind of my point, although I suppose I could have been more direct. I've known a couple people who have had issues with very low mileage, Genuine clutch cables purchased in the last year too.

[kgatesman]

The thinking was we could get the thing running for the Slaughterhouse XIX rally, which we didn't because of the electrical issues. Once that event was blown, the crank job became a priority.

Now the issue is SW can't pull the damn parts. "Maybe Monday" they will be back on line is the current status. Parts were ordered on Tuesday.

I haven't seen the part yet, but the theory is the crank is wobbly, and that caused the original ring to break. If so, my brand new head would have been doomed before long. Once I know for sure, I will post.

[Anachronism]

The thinking was we could get the thing running for the Slaughterhouse XIX rally, which we didn't because of the electrical issues. Once that event was blown, the crank job became a priority.

Now the issue is SW can't pull the damn parts. "Maybe Monday" they will be back on line is the current status. Parts were ordered on Tuesday.

I haven't seen the part yet, but the theory is the crank is wobbly, and that caused the original ring to break. If so, my brand new head would have been doomed before long. Once I know for sure, I will post.

How closely did you check the crank when you replaced the top end?

Failure at idle really sounds like the crank- its pretty damned rare to actually get a seize at idle, but its much more likely for a bad crank bearing to manifest the problem there.

When the rod bearing starts to go bad, it momentarily binds up, which usually can't be felt while running down the road, but can be enough to stall the engine at idle. I bike that unexpectedly stalls, but still has spark is a bike I would strongly suspect of having a dying crank.

Once the crank rod bearing starts going, the failure typically happens in 1 of three ways.

1. The binding crank puts a ton of sideloading pressure on the piston, because it is transferring rotational force instead of spinning freely. This will commonly cause a ring to catch the port and snap the ring. This was my second crank failure. 10 miles previously on its final ride, it had started the random stalls at idle deal, before I got to open road and ran it to death.

2. The crank bearing totally locks up and you practice grabbing both the clutch and willing your Sphincter to stay closed as your rear wheel locks. This is actually a preferred way for a crank to die as its the only chance your top end has.

3. The crank bearing disintegrates, spitting out bits of itself that quickly get drawn into the cylinder, where they destroy ports, destroy pistons, head, etc. If that wasn't enough, when the crank loses these parts the rod gets enough play to contact the head, and it will stay running this way long enough to hammer everything to death. This is the worst way for it to die, because it typically damages cases by catching stuff in the rotary pad area, it gets bits of shrapnel in the main crank bearings, the shrapnel can damage seals, and it basically makes a full rebuild including seals and bearings the only safe way to verify all the bad parts get out. This was my first crank failure.

[kgatesman]

My buddy thinks number 1 is the problem.

When I replaced the head, I was hoping to get a month or two of use out of the scooter then doing the crank because we just didn't have the money. Regardless of affordability, we are taking it all on now. The scooter will be better for it, but I am busted.

[kgatesman]

It took a week, but ScooterworksUSA is back in online. We should have our parts today, and the Stella back by the weekend.

[kgatesman]

Finally got it together. We haven't ridden it too hard, but it does seem to be zippier.

I would like to install a 24/24 carb before winter's over. Anyone have experience with this? Can I use the stock carb box? What is the story with using the P200 box? I have seen some talk of this mod too.