Carbs wont stop pi$$ing out fuel..........

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Rdnewbie
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Joined: Tue Nov 13, 2018 2:34 am

Re: Carbs wont stop pi$$ing out fuel..........

#16 Post by Rdnewbie » Tue Nov 13, 2018 12:55 pm

Hi, I had a problem like this on an RD and I found out I had the slides reversed, left on the right side... LOL

MK
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Re: Carbs wont stop pi$$ing out fuel..........

#17 Post by MK » Tue Nov 13, 2018 2:19 pm

Ivan_Ahrde wrote: If the pin sticks when you are out, often a sharp tap on the offending float bowl with a metallic object will free the pin up to get you home.
I advised that to a friend in the 90's for his RD350.
Short time later he was looking for a new float bowl as he penatrated it with the sharp end of a screwdriver. Should have told him not to use a sledge hammer ....
Bye
Martin

Brad Winchester
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Joined: Thu Jun 07, 2012 5:09 am

Re: Carbs wont stop pi$$ing out fuel..........

#18 Post by Brad Winchester » Tue Nov 13, 2018 6:14 pm

I had and are still having this problem intermittently. It seems everyone who owns a RZ500 have had this problem at some stage. I lowered the fuel level and seems to be fixed maybe. I haven't ridden my bike yet, in the last stages of a rebuild/restoration. I find the fuel level on a lot of 2 strokes to be too high when adjusted as per the manual. I often see fuel dribbling out of 2 stoke dirt bikes as they are ridden.
RZ500
ZXR900
FZ750x2
FZR250x2
ZXR250
GSX250
GPX250
Boulevard
KDX200 X 2
KX125
CR125
RMX250 X 2
KX80 X 2
YZ80

s4oz
Posts: 207
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Location: Melbourne, Australia

Re: Carbs wont stop pi$$ing out fuel..........

#19 Post by s4oz » Mon Jan 14, 2019 5:14 pm

Speed Freak wrote: Wed Oct 03, 2018 4:58 pm
4) In case of old valves and valve seats - corrosion and fuel components which will not evaporate.
Forget to ultrasonic clean them, it will not help. Polish the parts with an ear tip and metal polish.
The brass parts have to be shiny and smooth. Same with the sliding faces of the needle.
Never used new parts, polishing them makes them better than new and 100x better than aftermarket parts.

This was the single action that fixed the problem for me. It made a huge difference, from carbs leaking almost every time I started the bike when cold to almost never.

Luther
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Location: Obamagrad, Oklahoma

Re: Carbs wont stop pi$$ing out fuel..........

#20 Post by Luther » Mon Jan 28, 2019 8:58 pm

Yeah to Q tips and polish. Whatever gasoline had for lubrication in the past isn't there any more and i'm having better luck polishing seats, needle ends and sides, the spot where needle pushes float. You get the idea

Vin
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Re: Carbs wont stop pi$$ing out fuel..........

#21 Post by Vin » Sun Feb 10, 2019 12:39 pm

A simple tool l made to support the fragile posts while removing the pin.



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Vin
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Re: Carbs wont stop pi$$ing out fuel..........

#22 Post by Vin » Sun Feb 10, 2019 12:43 pm

Here are the picsImageImageImage

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silverstrom
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Re: Carbs wont stop pi$$ing out fuel..........

#23 Post by silverstrom » Sun Feb 10, 2019 5:57 pm

If you use a spring loaded centre punch to remove the pin you can avoid damaging the posts.

MadDogRoger
Posts: 33
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Location: Belgium

Re: Carbs wont stop pi$$ing out fuel..........

#24 Post by MadDogRoger » Fri Mar 01, 2019 8:38 pm

Hi all,

An update on my carbs.
I didn't do much over the winter, it's too cold in the garage.
But since we had some warmer weather the last couple of weeks I set out to finishing the carbs.

Since the floats were kinda crooked, I figured I'd start with setting them straight. Dismantling them (very gently) and then with a hammer, anvil and driver very gently straightening all the bends, gave me a good looking float.
But even more importantly when mounted it would now stop against a small lip where it wouldn't before.
Before it would lower more than it should, getting just a tiny bit stuck (thus preventing from coming up) AND pulling the float needle further down than it should be pulled. Allowing it also to get a little bit stuck.

Having corrected this on all the carbs, put everything back together, put the carbs back on the bike, took me three hours on the left side alone.
I fitted new fuel lines and it turns out the routing is super critical. The new lines didn't have the same curves as the old ones so it was a bit fiddly to say the least.
But anyway, everything back together, fuel in, fuel tap to prime, back to on and motor running :smt003 :smt003 :smt003
Even today, after two days: no leaks :smt003 :smt003 :smt003

Another box to tick.

Started working on mounting the fairing and have the rear side panels in place with new bushings.
I think it's looking good to get some km in this year.

Thanks everyone for your help, couldn't have done it without you guys :smt006

Greetz,
Mad Dog Roger

silverstrom
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Re: Carbs wont stop pi$$ing out fuel..........

#25 Post by silverstrom » Fri Mar 01, 2019 9:40 pm

Success!

Persistence pays off. Well done. Hopefully that headache stays away for years.

lost1750GTV
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Re: Carbs wont stop pi$$ing out fuel..........

#26 Post by lost1750GTV » Fri Mar 01, 2019 11:43 pm

aah, a success story to emulate when I get back to it. just one for me... I think ....
but now I'm distracted by my new beta 200rr, and that could continue through spring

Linx
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Re: Carbs wont stop pi$$ing out fuel..........

#27 Post by Linx » Sat Mar 02, 2019 5:29 am

Well done. Sounds like you did a good thorough job there 👍.
:smt006 Current Bikes
1984 47X RD500LC, 2018 Triumph Speed Triple RS, 1999 Honda CB600F Hornet
Past Bikes Include
RD250LC, RD350YPVS LC2 Race Bike, RD350F2, 1976 CB400F

MadDogRoger
Posts: 33
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Location: Belgium

Re: Carbs wont stop pi$$ing out fuel..........

#28 Post by MadDogRoger » Fri Nov 01, 2019 4:15 pm

Hi all,

It's me again with another fuel story :shock:
Got back from a sweet ride last week. Put the bike back in the garage and started mowing the lawn. When I was finished with that and came back in the garage I noticed a very strong petrol smell.
I figured it was from the petrol can I used to fill up the lawnmower. As it turned out it wasn't the petrol can.
A big puddle of fuel had formed below my RD, and it was dripping hard.
"Darn those carbs again", went through my head. So out the flashlight and started looking for the leak.
Well it wasn't coming from the carbs but from higher up, even higher than the fuel tap. So up with the tank and yes I had a leaking fuel line just below the tank.
The line didn't look as it had been pinched but there was a clear "cut"-like leak.
It was dripping right on to the exhaust! If this had happened while riding .... :smt017

I bought new fuel lines but it still wanders in my mind. About a year ago there has been a change in fuel. Here in Belgium we now have Super 95 E10 and Superplus 98 E5.
And you guess right when you say Super 95 has 95 octane number and 10% ethanol in it. Superplus is 98 octane and 5% ethanol.
As you can see I cannot choose a fuel without ethanol. I only use Superplus (even though it is more expensive) because of the lower ethanol.

As I understand ethanol is bad for oldtimers because of the ???? yes what really. Maybe some of you guys have some actual knowledge about this.
From what I picked up, the ethanol doesn't quite agree with older types of rubber.

So now I'm thinking about changing the remainder of the old fuel lines for new ones but even then I'm wondering if there are any other bits (seals/rubbers) inside the motor that may be affected and should be changed and what are the consequences if they aren't changed?

As always, any input is greatly appreciated.

Thanks in advance,
Roger

craig_johns469
Posts: 36
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Location: Perth, Western Australia

Re: Carbs wont stop pi$$ing out fuel..........

#29 Post by craig_johns469 » Fri Nov 01, 2019 8:00 pm

G'day Roger

I looked into E10 fuel a few years back (when it first started appearing in Australia) with regard to boating as engine reliability is of the highest importance when fishing offshore.

I found the main concern at the time was starting the use of E10 in an older fuel system that had been used for petrol for many years and had formed a 'varnish'. I believe ethanol breaks down this varnish with the result being the potential to clog fuel filters so I simply avoid it since and not risk being stuck in the middle of the ocean awaiting marine rescue while hoping the weather doesn't turn. I also tend to drive older cars too so avoid it in general as although I cover myself with a reputable break down service, I don't want the hassle of having to have a car towed, replace filter, potentially pump, injectors etc.

I had a bit more of a look when I saw your post to see if I can justify my general avoidance of E10 and found this article which contains some interesting info:

https://www.westmarine.com/WestAdvisor/ ... Fuel-Myths

It focuses more on the resulting water in the fuel which for a boat without a huge tank, could be protected against by a fuel filter with water separator (which I have on my boat but not on my 500!), as long as it's checked regularly but does also touch on filter clogging, again from the break down of 'varnish' or 'gum' through years of petrol usage.

So for a 35 year old bike that has been running petrol all its life, if this article is accurate, there is a reasonable chance that you may run into issues being forced to now use E10, not so much around fuel lines which are easy to replace (except on a 500 unless you have hands the size of a 6 year old's! ), but the tank, which is er... Not so easy to replace.

Definitely worth investigating further, perhaps being very anal with checking fuel/filter and draining off/swapping out fuel regularly, at least in the short term, to ensure water build up doesn't become a problem, obviously having some pretty nasty consequences.

I guess we're lucky in that we're not forced to use E10 although I did also hear at the time that fuel suppliers are allowed to include up to 10% ethanol in fuel without declaring it anyway so perhaps we've been using it on all this time (depending on where we fill up). I simply avoid using fuel specifically marked as E10 and use Premium 95 as a minimum or generally Premium 98 in anything of importance, despite being advised by someone very "knowledgeable" (!) a few years ago that 98 is "too clean" for older motors which prefer a less refined fuel. I'll stick with premium quality fuel and synthetic oils for my 2 strokes thanks!

Looking forward to reading other people's opinions and experiences on this as I'm sure there are many that have done some investigation, particularly in countries that have been forced to us E10 over recent years.

Cheers, Craig

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Speed Freak
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Re: Carbs wont stop pi$$ing out fuel..........

#30 Post by Speed Freak » Fri Nov 01, 2019 9:05 pm

Old vehicles use NBR rubber seals and fuel lines.
This rubber is not resistant against ethanol.
At first the rubber starts growing and gets softer. As soon as it dries up it shrinks and gets brittle.
Modern vehicles use HNBR or other rubber compounds.

One good point is that E10 can transport water out of the fuel tank.
As long as the fuel gets used up from time to time there will never be a water bubble in the tank.
Such a water bubble destroyed my nice RD350 tank.
No rust... except at the lowest place where it rusted thru from the inside.
My bikes:
RD500 YPVS 1GE
RD350 YPVS 31K 1985
Honda CBR 1000 RR SC57
Yamaha R1 RN04

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