Ex-500.com - The home of the Kawasaki EX500 / Ninja 500R banner

1 - 20 of 24 Posts

·
Registered
Joined
·
1,489 Posts
Discussion Starter · #1 ·
hello. question for @ducatiman or anyone who wants to chime in. is there a way to reprofile the float seats or do a better job of cleaning the float valves other than the usual ultra sonic and or cotton bud.
got a strange issue. if I leave the bike parked longer than a week when the fuel is turn on the carbs flood out. a tap with something on the bowls seems to work until next time. then it does it again.
happened this morning after 8 days parked up. however tapping the bowls made no difference. just wouldn't stop running out. so I removed the carbs set them up on the bench for wet test (without doing anything to them) apart from taking them off.
set them up with remote fuel source, no leaks bone dry. and the levels are where they should be.
obviously there is a issue with the float valves somehow but what. for the last 6 hrs they have been sat under test (fuel turned on) levels are still ok. and still no leaks (any ideas) what to do next.

to be honest I've had this issue a while. usually when it occurs turn off the fuel start the engine tap the bowls let it run the levels down fuel back on (no leaks) it never leaks while riding or if the bike is used daily.
I have tried leaving it with the bowls full. (petcock off) and also running it down until the carbs are empty. makes no difference carbs leak on start up.
at the last service 1k ago it got a full service kit new valves ultra sonic clean. and blow though with air I'm part figuring the float seats may be dodgy but why would it not leak any other time except after being parked up.
any ideas welcome.

54441
54442
 

·
Registered
Joined
·
593 Posts
The tap-to-fix makes it seem like the float valves are hanging up on something, but then I imagine they'd leak all the time and not just after extended number of days if that were the case.

How new are the float valves? Are the tips in perfect condition. Ever so slightly not-quite-right might be the reason that an extended period of time is causing the leak? I'd consider replacement.

As for the float seats, I use a cotton bud in a dremel with some mag wheel polish. This creates a very clean seat, and the polish is good at making sure there are no small imperfections.
 

·
Super Moderator
Joined
·
15,401 Posts
the carbs flood out
just wouldn't stop running out
carbs leak on start up.
Precisely where are they leaking from?

PS your pic #1 float level appears high

it is conceivable you've got incorrect float valves. I believe some years ago I documented a couple of different types sold as fitting EX500....but clearly differing lengths. Caused me to stick with the same (correct) source for years now.
 

·
Registered
Joined
·
19,569 Posts
Fact is , like all other components of this bike the carbs are crap. very bit of them is just barley able to do it's job when all is well. Even the tilt of the side stand is enough to mess up the float valves.
All you can do is remember to turn off the petcock even for a short stop.
I had a set of Weber 40 DCOE carbs on my Lotus, they were made like fine watch or jewelry .
These KN are not'
'FOG
 

·
Registered
Joined
·
1,489 Posts
Discussion Starter · #5 ·
thanks for the replies guys to answer in order.
how new are the float valves? Are the tips in perfect condition. Ever so slightly not-quite-right might be the reason that an extended period of time is causing the leak? I'd consider replacement.

As for the float seats, I use a cotton bud in a dremel with some mag wheel polish. This creates a very clean seat, and the polish is good at making sure there are no small imperfections.
carbs were redone last year. only done 1k on them due to Covid lockdowns. kits came from Keinin direct (japan) so original equipment. all the serviceable parts came in the kit inc new floats. needles. needle jets. jets. jet holders. ECT. and gaskets.
will try the polish trick thanks.

Precisely where are they leaking from?

PS your pic #1 float level appears high

it is conceivable you've got incorrect float valves. I believe some years ago I documented a couple of different types sold as fitting EX500....but clearly differing lengths. Caused me to stick with the same (correct) source for years now.
its hard to tell on the cruiser. the carbs are mostly buried I assume it's from the air vent, it runs off the drain ports at the btm of the float bowls.
the levels are near. could be the angle the shot was taken from. there is a slight difference. the left one is 1mm above the line. the right one 1mm below not ideal I know but within spec. I will adjust them while stripped.
valves are correct (see above) unless someone made a mistake in japan. the other set of kits I put on the gen 1 give no issues at all. yes I bought two kits (ouch) but were fed up of aftermarket rubbish and leaking seals.

Fact is , like all other components of this bike the carbs are crap. very bit of them is just barley able to do it's job when all is well. Even the tilt of the side stand is enough to mess up the float valves.
All you can do is remember to turn off the petcock even for a short stop.
I had a set of Weber 40 DCOE carbs on my Lotus, they were made like fine watch or jewelry .
These KN are not'
'FOG
yes we know. point taken surprisingly though how some run for over 30 years and/or 100k. also the EX's little brother the 305 uses the same carbs (although smaller 30mm) and that bike ran 5 years (30k) without any carb issues at all.

since my last post I have taken the bowls off nothing to see here amiss (unless I can't see it)
bowls are spotless.
54443


so are the bodies. even the seats look good and clean.
54445
54446
54444
 

·
Super Moderator
Joined
·
15,401 Posts
I assume it's from the air vent, it runs off the drain ports at the btm of the float bowls.
it is conceivable that between the slightly high fuel level in 1 carb being exacerbated by sidestand tilt.....see (if it continues) if you can nail down precisely where its from.
 

·
Registered
Joined
·
1,489 Posts
Discussion Starter · #7 ·
hi. it wasn't on the side stand but on that contraption I made so it was upright. I will clean the seats in the morning, check the operation of the floats. reset them and see how it goes.
 

·
Registered
Joined
·
371 Posts
VALVE-FLOAT
16030-1007

The rubber tip is no good due to either poor manufacturing or spending too long on shelf before purchase

OR

little inside spring is too weak, the tip gives way under constant pressure; due to poor manufacturing.
 

·
Registered
Joined
·
1,489 Posts
Discussion Starter · #9 ·
hi guys. thanks for all the replies.
I'm thinking nay hoping I have found the answer. this morning I inspected the carbs in fine detail. cleaned the float seals checked all the seals. then saw something odd. one of the vent holes in the float bowl was blocked the other was open (opposite ends of where the vent pipe fits) after separating the carbs noticed one was still blocked. on further inspection it appeared there was a bit of tube stuck in the end. after digging it out it seems to be a bit of broken vent tube.

then got a Dumbo moment. it must have been there since building the bike. no idea why I never noticed it before. the carbs on the cruiser are the best bits from two sets of spare broken carbs. and must have been in there when built.
if one carb is not venting it must be pressurising could account for a lot plus on that side the vent tube cannot have been sealing. hope this is the answer. will find out on reassembly when tested.
54447
 

·
Super Moderator
Joined
·
15,401 Posts
WTF? if the pictured broken piece was installed , it would prevent the complete vent tube from installation. Something not adding up here.
 

·
Registered
Joined
·
371 Posts
"Something not adding up here."

Also don't understand how "tap on the bowls" would affect that piece, but okay, if replacing the vent piece solves the problem.
Saved me the trouble of packing up a few float valves and Air Mailing across the Pond.

Happy riding, cheers!
 

·
Registered
Joined
·
2,605 Posts
If the overflow persists, give this a try: pop the petrol cap loose and leave it resting against the filler neck. Stranger things have happened, but the cap vent may be stopped up and the tank is slightly pressurised. You'll know in a few days time.
 

·
Super Moderator
Joined
·
6,623 Posts
I thought it was hard putting a square peg in a round hole. Must be a real b**** putting 2 pegs in one hole. Check and see if you can find the kitchen sink back there. 😆
 
  • Like
Reactions: auburn

·
Registered
Joined
·
1,489 Posts
Discussion Starter · #14 ·
WTF? if the pictured broken piece was installed , it would prevent the complete vent tube from installation. Something not adding up here.
actually there is (just) the vent tube when inserted only goes 1/2 way into the carbs. so the broken piece must be short enough to be pushed to the end blocking the far end but allow the vent tube to fit (otherwise the carbs would not join) yes it is tight but it was in there. possibly it's big enough to stop the O ring sealing (could have been the leak issue) if combined with blocked vent and high fuel level. Dunno. it is all I found wrong. float valves are fine carbs clean. and now the levels are correct and it's venting there is no leaks. left them hooked up to the remote bottle for a further 4 hrs no issues. bike starts runs fine of course I will have to re balance them now they have been split and tweak the pilots.
next time it's parked up i will find out if it's cured.
"Something not adding up here."

Also don't understand how "tap on the bowls" would affect that piece, but okay, if replacing the vent piece solves the problem.
Saved me the trouble of packing up a few float valves and Air Mailing across the Pond.

Happy riding, cheers!
neither do I but it's all I found . plus after removing the carbs and hooking up the remote bottle to wet test them. they didn't leak. thanks for thought man most appreciated.

If the overflow persists, give this a try: pop the petrol cap loose and leave it resting against the filler neck. Stranger things have happened, but the cap vent may be stopped up and the tank is slightly pressurised. You'll know in a few days time.
hi. this issue has persisted since I build the bike. always the same. used daily no problem. used weekly mostly no issues. parked more than 2 weeks. it leaks when the petcock is turned on. so turn off the petcock, start the engine, tap the bowls, let it run for a minute. turn on the petcock , no leaks. the issue wasn't dependant on weather or length of time left. if over 2weeks. last time (just yesterday) it had been stood (over winter) for 5 months. and didn't stop leaking as before or I wouldn't have bothered. by the way it used to do it no matter whether it was left with the bowls full (petcock off of course) or dry by running the engine until it stops or draining the bowls. made no difference.

I thought it was hard putting a square peg in a round hole. Must be a real b**** putting 2 pegs in one hole. Check and see if you can find the kitchen sink back there. 😆
HA HA. I never noticed it was in there when I built the carbs. my bad. and no sink but I found a camping stove in the air box. :):):)
 

·
Registered
Joined
·
2,605 Posts
 
  • Like
Reactions: bpe

·
Super Moderator
Joined
·
15,401 Posts
@yorkie........I request a current pic of found errant piece of vent tube.
 

·
Registered
Joined
·
1,489 Posts
Discussion Starter · #18 · (Edited)
as requested. the tape is for scale. "note" the O ring that was on the end has been lost.

54456


I think at this point I should add a correction, just to clarify.

I said that the issue had been there since I built the bike that is not absolutely correct but a generalisation of carb issues.
I have had this particular issue since building the carbs not the bike. so for the last two years. it did not change after fitting the OEM kits I got from Japan.

when I built the bike I had no carbs for it. so borrowed the set off the gen 1. completely untouched. got the bike running but as I had to run pods (no room for a stock airbox) it ran crap (as it would) not wanting to play with the carbs off the gen 1, I bought a pair of flat slide "OKO's" to play with got the bike running quite well but there was always something missing. there was no where near me to take it to for fine tuning.

while it was just a fun used occasionally bike, I made it do but when the gen 1 came off the road for it's second refurb. the cruiser had to run well and be used daily.
this is when I bought two broken sets off E-bay. made one good set out of the bits and fitted them in stock form.
I fabricated a cut down airbox to use and got it running pretty well near perfect. except for the fuel leak when parked up. the bit in the right carb must have been in there since then.

so to summarise the bike has been usable for 3 years these carbs have been on 2 years.
 

·
Super Moderator
Joined
·
15,401 Posts
the locating "nub" is still present on the side not visible?
 
1 - 20 of 24 Posts
Top