Sodding MZ

In communiqué <1iyey15.12rqps10hioetN%>,

Sure the spark is good and strong - tried a spanking new plug?

Sounds as if you may have fuel in the crankcase. You should know the
drill - plug out, fuel off, empty the float bowl, throttle wide open and
kick, kick, kick. Leave the plug out for a bit then try again.

If it won't go then you really need to check the ignition timing, but I
don't know whether it can 'slip' catastrophically on those.
--
+----------------------------------------------------------------+
| Pete Fisher at Home: |
| Voxan Roadster Gilera Nordwest * 2 Yamaha WR250Z |
| Gilera GFR * 2 Moto Morini 2C/375 Morini 350 "Forgotten Error" |
+----------------------------------------------------------------+

 

It deep ends on how long it had been sitting around unused.
Pushed gently out of garage - starts.
Good shaking up = fuel/water/shite mix blocks pilot jet, then flooded
by attempts to start.

Sounds as possible as any other theory.
Take the fuel pipe off the carb and fill a glass jar - what does it
look and smell like. Cloudy = water, brown = rust&shite.

 

Does it fire with a new plug and a good squirt of StartYouBastard ?.
If it fires something is blocked in the carb.
CAUTION - Ether spray does not have 2stroke oil so dont try to keep
it running too long on spray.

 

It looks like normal petrol. *Shrug*.

I left the plug out of the pot for a few hours, and tried again, and it
started!

But now it won't.

 

Sticky float needle?

 

Nope. Took the float bowl off this afternoon and checked.

 

The Older Gentleman wrote:

Wotcha.

The stuff in the tank is indeed petrol - or at least that's what I put in
it, and it's been running around happily on the first half of the tank's
contents.

This is getting silly.
MZs are ugly, but they are reliable.
It's going to be something so bloody obvious. . . . . hindsight is a
wonderful thing.

 

HEH.

The LE did one of those on me last week. One of the spade terminals had
come off its spade on one of the coils but was jusssst resting against
it. Starts - runs for a while - dies - wont start - starts .....
The LE has an ammeter so the fault was kinda obvious when I noticed the
needle not moving when I kicked it over.

 

Well, on Sweller's advice I'll try a new plug, though both the plug
that was in it and an old spare I had knocking around both sparked
happily. If that fails, I'll check the timing. If that fails I'll
break the bastard thing for parts.

I wanted a bike to fiddle with, not one that would drive me into an
impotent frenzy.

 

In communiqué

There's 'spark' and 'SPARK' that can make a difference even with four
strokes IME. The tuned Nordwest could be a sod to start from cold when I
first built it. You could see what seemed like a good enough spark, but
it wouldn't start. In the end I went a grade softer on the plug, though
TBF fiddling with the air gap between the pip on the alternator rotor
and the ignition sensor also helped a lot.

Heh, time to look for a Morini again for a double whammy ;-)



--
+----------------------------------------------------------------+
| Pete Fisher at Home: |
| Voxan Roadster Gilera Nordwest * 2 Yamaha WR250Z |
| Gilera GFR * 2 Moto Morini 2C/375 Morini 350 "Forgotten Error" |
+----------------------------------------------------------------+

 

Sounds like it was flooded, leaving the plug out allowed it to start but
maybe you still have a load of fuel in the crankcase.
Next time it starts keep it running for at least half an hour.

OTOH, how much will you pay me to take it away ?.

 

I find that it helps to fully charge the battery and then keep the charger
attached while trying to start. The odd few extra volts can make a big
difference on 6v systems. If this works it is time to start cleaning and
checking every connector. Evil bastards (like me) have been known to hot
wire the coil to a 12 volt battery - best not for too long though.

 

This is possible.

Indeed. Watch for a smoke pall over Sutton.

 

You're not being a help here, Mister Fisher.

 

I was wondering that too.

Assuming (a) it's reed-valve and (b) the valve isn't 'perfect' (i.e. per
usual, leaks like a really leaky thing)... can you remove t'plug and set
the piston below the transfer port(s), to help the crankcase fuel
evaporate?

I assume there isn't any sort of crankcase drain.

There always is these days: it's those poor banking home-workers burning
the documents.

 

On an old MZ? Bwaaahahahahahahahahaha!

<Wipes streaming eyes>

There isn't. I drained the carb, removed the plug, and kicked it over
a number of times. It's been sitting since yesterday afternoon with
the plug out, and I'll shove a new plug in this evening, turn on the
fuel, and see what happens.

 

In communiqué

I had a struggle with the chainsaw at 'the chateau' last October.
Started first pull but quickly died. Much swearing and heaving on the
cord only succeeded in flooding it. In the end, I drained it of fuel,
removed the plug and the rudimentary silencer and left it turned upside
down for a wile. Not exactly an option in your case though.

Classic MX/hill climb treatment for a 'gassed up' stroker is to lean it
over on one side whilst revving the tits off it once you do persuade it
in to life. That is also a strategy in the case of shagged oil seal
though. Enough smoke to elect the whole college of cardinals.

--
+----------------------------------------------------------------+
| Pete Fisher at Home: |
| Voxan Roadster Gilera Nordwest * 2 Yamaha WR250Z |
| Gilera GFR * 2 Moto Morini 2C/375 Morini 350 "Forgotten Error" |
+----------------------------------------------------------------+

 

Sorted!

It was the plug. And my spare one was duff as well, believe it or not.

 

In communiqué <1iyhjro.1dh9q2119vz874N%>,

Oh, I do, I do. BTDTGTTS. Always worth trying a new plug before more
radical fiddling.



--
+----------------------------------------------------------------+
| Pete Fisher at Home: |
| Voxan Roadster Gilera Nordwest * 2 Yamaha WR250Z |
| Gilera GFR * 2 Moto Morini 2C/375 Morini 350 "Forgotten Error" |
+----------------------------------------------------------------+