Clearing Flooded Cylinders...

....preferably without the use of a blowtorch.

The GSXR (400 GK71F) hasn't started since my uncle had it running the other
night, and since I'm not putting it on the road until I've sold the goose, I
figured that now would be a good time to strip the carbs.

Took them out, cleaned the jets and other bits and pieces. Wrote down what
jets were where for future reference. Why are 1 and 3 running on 100, while
2 and 4 are running on 96? I would of presumed that all the jets would be
the same.

Anyway, put the cleaned out carbs back on, and the bike still didn't start.
Took the plugs out which appeared wet, implying that the cylinders were
flooded(?) probably from trying to start the bike.
Cleaned of the plugs and reinserted them. Pressed the started, got a couple
of backfires, then back to nothing again[1]. Took the plugs out, which were
wet again.

The bike turns over, but won't make any attempt to catch, so I've left the
bike with the battery on charge.

So, is the flooding why the bike won't start, and how do I clear the
cylinders?

[1]Also tried with the choke off and throttle fully open, as heard this
helps get more air in with flooded cylinders?

 

Leave the bike and let them drain into sump, or turn it over
without the plugs in and stand clear.

--
Cammo
VT500 Rat
GSX750SE Katana
GT250-X7
GT380
http://cammo.webs.bikers-engine.com
cammo at bikers-engine dot com

 

Have you asked on microsoft.public.excel.misc ?

 

Usually they are the same. I'd have expected the outer pair to run the 100s
and the inner pair the 96s or all 100s, not 1+3,2+4 like that.

You have got the plug leads back on the correct plugs haven't you. If you
have them crossed up, the plugs will spark, but not at the correct time and
you will get an occaisional backfire. Usually paired 1+4,2+3

Remove the plugs, ground the HT leads -well away from the plug holes- turn
engine on starter for a few seconds.

Yes and no. Mostly yes. With the plugs in, there will be a pressure drop as
the piston descends, which will draw fuel. Nowhere near as much as when the
engine is running, but some fuel will get through.

 

So why aren't they :- /

Yeh, sparks on all 4. I left the plugs out while I went to work, then gave
the cylinders a blowout with the airline when I got in (with a long stick
attatchment, so I didn't blow shit in) and it fired up ok after that, so I
think it was just flooded.

<This is where my sig would be if I had quotefix>

 

I'll ask on one of the GSXR400 forums.

Yep, they're even numbered for the terminally stupid.

Left the plugs off while I went to work, then gave the cylinders a blow out
with the airline when I returned. Seemed to do the trick.

OE...

 

It can happen, because of airbox flow characteristics, that air
distribution to the carb intakes isn't even. I've come across ones where
the middle two are running ok, but the outer two are a bit on the
airstarved side and have slightly smaller jets as a consequence.

Yours seems to be arse about tit, so I wonder if someone has swapped
over the jets when rebuilding the carbs.


--

Dave

GS 850 x2 / SE 6a
SbS#6 DIAABTCOD#16 APOSTLE#6 FUB#3
FUB KotL OSOS#12? UKRMMA#19 COSOC#10

 

We were thinking along the same lines. There are legit reasons why you could
need two different jet sizes, but we can't think of any why they would be
run in that order.

The guy who set it up is either a genius, or was totally wankered at the
time.

 

I thought it was more to do with the inboard cylinders getting less
cooling, so are setup with a slightly richer mix to keep things nice and
cool.

 

Possible; but I wonder if that reason would lead to a benefit or not.
<shrug>
Who knows the mysterious way of the designer. Whatever; it seems to
work, but there is obviously a limit on how different the outer/inner
cyls can be to each other.

--

Dave

GS 850 x2 / SE 6a
SbS#6 DIAABTCOD#16 APOSTLE#6 FUB#3
FUB KotL OSOS#12? UKRMMA#19 COSOC#10

 

My Bandit is fitted with different inner / outer cylinder jets, but the
dyno jet kit has all the same jets for some reason. Who knows...