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Discussion Starter #1
Hi All,

I have a old Intruder 750 86 I am fixing up. I have attempted and finally got the bike to start, but fuel is pumping out of a hose on the rear carb everytime I start the bike.

I don't have a manual and am not sure the manual would cover this anyway.

It is pumping out of a hose on the right side of the rear carb. The hose is clear, does not have an hose fasteners, is only 10cm long. one side is connected to the carb and one side is just pointing down - like it is mean to be a overflow of the carb or something.

I think is is cable 13 if you google "(09352-50823-600) HOSE VS750GL 1985 (F) (E02)" and select first result (soory I assume the forum rules would not like actual links to websites posted).

Can anyone confirm if this is a sort of breather or overflow and if so why fuel is poring out. Or is it possible something is not hooked up right?

There is the same hose on the front that does not seem to be leaking.
 

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Discussion Starter #2
Oh and incase I did not express this right, it is only happening while running and with the fuel tap on. Stopping the bike the fuel stops, turning the fuel tap off while the bike is running the fuel stops. It is almost like the hoses are back to front (as there is a second hose right beside it leading to the top carb), but it is also seemingly running fine on both cylinders suggesting this is not the case.
 

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Discussion Starter #3
I think I have confirmed the hoses are not around the wrong way.

1. I swapped the hoses and the same thing happened.
2. I inspected the top carb, it has the fuel hose between the 2 carbs on a end that has "raised rings" on the copper outlet (not smooth lie the other hose outlet), and that is the same as the rear carb was. Both have a smooth outlet that seems to be a breather or something.

Is anyone able to confirm what the problem might be and the fix?

Thanks,

Glenn
 

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The line you describe sounds like an overflow pipe for that carb. I would suspect the float is either sunk...(has a hole/leak in it) or the float/needle has stuck or the needle is failing to seal the float jet when the float has reached its upper level. If its the latter you may want to check your oil for fuel contamination....if this has been happening for some time.

You may be lucky and its just a bit of crap under the float needle tip. The offending carb will probably have to be removed and the float/needle inspected. The needle tip must be smooth and free from any ring, typically near the tip and wear from the float jet, or nicks. The float height will need to be checked against specs....to find these you may need to access a specific forum for your model/make.

The float must move easily and have no tight spots. Most float heights are taken from a point on the float to a point on the joint surface of the carb. Some have to have the spring loaded float needle tip (if fitted) not depressed. Some carbs have the measurement done upside down and others the right way up depending on the linkage action upon the float needle.

Make absolutely certain the needle tip is clean and also the fuel metering jet it fits into...even a tiny speck of crap can cause the system to leak.

The rings you speak of on the pipes that the fuel hose fits to are ridges to help prevent the hose from slipping off due to vibration etc. They should also have some sort of spring clip too.


Good luck
 

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The offending carb will probably have to be removed and the float/needle inspected.
Steve about has it covered.

On some models and if you are somewhat of a contortionist, you can access the float and needle valve by removing the float bowl without removing the carb.
In most cases, however, that won't work.

This is happening the way it is because the fuel valve (petcock) is vacuum controlled and shuts off the fuel flow when the engine is not running.
If you have a PRIme setting on the petcock, using that should make the carb overflow leak again.

Long shot: While the leak is occurring, (use PRIme setting if you have that so the engine is not running) rap on the offending float bowl with the handle of a screwdriver a few times. That might break something loose and stop the leak. If it does, then a follow up with a good carb cleaner might finish the job. But it is a long shot.

P.S. This situation is probably letting some gas into the oil. After it's fixed and oil change would be in order.
 

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Discussion Starter #6
Thanks for the information, was hoping something simpler as the carbs are a pain to get out. I suspect it os a stuck needle or float as the bike was sitting for a while and the bowls of the carbs were empty before I tried to start it.
Thank you Steve.
 
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