Fuel coming out of air vent tubes on carbs

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Fuel coming out of air vent tubes on carbs

Postby Barbie & Skipper » Thu Dec 06, 2018 2:42 pm

Well, I was hoping that Skipper wouldn't need me to dive into the carbs, as she was parked with the carbs & tank dry. When I hooked up fuel, and started cranking, fuel started pouring out what I believe to be the air vent tubes. I'm attaching a pic with the screwdriver pointing to the two tubes where fuel was coming out.

Barbie's new tires just arrived, so Skipper will be on the back burner for a bit, but I'd appreciate any insight on what might be causing this problem.
Attachments
vtr250_carb_leak_IMG_20181206_121831.jpg
Barbie - 89 VTR250 - 6k+, back on the road.
Skipper - 90 VTR250 - 36k+, painted black & white, "ran when parked", upcoming project.
Parts bike - 90 VTR250 - 22k+, "maintained" by idiots, but mostly complete, no title.
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Re: Fuel coming out of air vent tubes on carbs

Postby ExTex77 » Thu Dec 06, 2018 4:27 pm

I find that float bowl overflow does occur when the bowls are allowed to go dry for an extended period of time.
The floats are then extended to their max. low positions and the needle valves are extended to their max. lengths.
Looking at the leverages applied, those extreme positions make it difficult (or impossible) for the valves to return to working properly.
One valve (or both) stay open and the gasoline flows and then overflows.

A gentle to moderate tap on the float bowl with a non-metallic hammer (piece of wood) will usually create sufficient vibrations
and the needle valve(s) will go back to working.... and there won't be another problem until the next dry season (and maybe not even then).

So turn on gas and tap on the float bowls ( or even the carb bodies.). That should work or else you will have to delve into the floats and needle valves.

Merry Christmas,
ExTex
1989 Honda VTR250 & 1988 Honda NT650
Wife rides a Burgman 200 scooter and I enjoy riding it also
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Re: Fuel coming out of air vent tubes on carbs

Postby squirrelman » Thu Dec 06, 2018 6:03 pm

get into the carbs cuz long periods of sitting will usually clog things up. you may need to clean up float needles and seats as well as idle jets.

don't want to deal with it ?? pull carbs off and send them to me for professional cleaning, rebuilding and adjustment. i've fixed carbs for several members here and dozens on the VFR websites. ;)

8--1--17 012.JPG
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Re: Fuel coming out of air vent tubes on carbs

Postby Barbie & Skipper » Fri Dec 07, 2018 9:55 am

squirrelman wrote:get into the carbs cuz long periods of sitting will usually clog things up. you may need to clean up float needles and seats as well as idle jets.

don't want to deal with it ?? pull carbs off and send them to me for professional cleaning, rebuilding and adjustment. i've fixed carbs for several members here and dozens on the VFR websites. ;)


Thanks. I was hoping storing dry would have alleviated the issues.

Are float valves available for the VTR? It probably would be worth swapping them out if I could find new ones. Ideally, if I could find a set of 4, I'd swap them out on both bikes as a precautionary measure.

Thanks for your offer. It's more of a case of "I'd rather not have to open up the carbs." than "I dread having to open up the carbs." I'm up to about 30 carb rebuilds so far, but it has been a few years, and I'm re-learning some things that I had forgotten.

Do you have a thread for services offered in the Buy/Sell/Trade section? I didn't see one.
Barbie - 89 VTR250 - 6k+, back on the road.
Skipper - 90 VTR250 - 36k+, painted black & white, "ran when parked", upcoming project.
Parts bike - 90 VTR250 - 22k+, "maintained" by idiots, but mostly complete, no title.
Barbie & Skipper
 
Posts: 32
Joined: Fri Nov 16, 2018 5:12 pm

Re: Fuel coming out of air vent tubes on carbs

Postby ExTex77 » Fri Dec 07, 2018 11:30 am

I recently bought & received the following for my VTR250 carbs:

Repair kits: https://www.ebay.com/itm/263177055404

Hex head bolts for float bowls: https://www.ebay.com/itm/172719522251

Not installed them yet. but good prices and fast delivery.

Ride safely,
ExTex
1989 Honda VTR250 & 1988 Honda NT650
Wife rides a Burgman 200 scooter and I enjoy riding it also
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Re: Fuel coming out of air vent tubes on carbs

Postby Barbie & Skipper » Fri Dec 07, 2018 4:12 pm

ExTex77 wrote:I recently bought & received the following for my VTR250 carbs:
Repair kits: https://www.ebay.com/itm/263177055404
Hex head bolts for float bowls: https://www.ebay.com/itm/172719522251
Not installed them yet. but good prices and fast delivery.
Ride safely,


Thx. I ordered the pair of K&L 18-5214 kits. I'll tackle Skipper's carbs when they arrive.
Barbie - 89 VTR250 - 6k+, back on the road.
Skipper - 90 VTR250 - 36k+, painted black & white, "ran when parked", upcoming project.
Parts bike - 90 VTR250 - 22k+, "maintained" by idiots, but mostly complete, no title.
Barbie & Skipper
 
Posts: 32
Joined: Fri Nov 16, 2018 5:12 pm

Re: Fuel coming out of air vent tubes on carbs

Postby squirrelman » Fri Dec 07, 2018 6:42 pm

Needle seats don't suffer any real wear, so why replace them $$ ?? for fuel overflow just replace the $6 float needle, not the whole set. with hexhead screws there is some danger of over-tightening and carb damage, which is impossible with stock screws.the float bowl gasket can cheaply be replaced with a -041 standard Viton O-ring. :roll:
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Re: Fuel coming out of air vent tubes on carbs

Postby Barbie & Skipper » Sat Dec 08, 2018 4:54 pm

squirrelman wrote:Needle seats don't suffer any real wear, so why replace them $$ ?? for fuel overflow just replace the $6 float needle, not the whole set. with hexhead screws there is some danger of over-tightening and carb damage, which is impossible with stock screws.the float bowl gasket can cheaply be replaced with a -041 standard Viton O-ring. :roll:



Thanks. Do you have the part number and/or a link for the correct float needles?
Barbie - 89 VTR250 - 6k+, back on the road.
Skipper - 90 VTR250 - 36k+, painted black & white, "ran when parked", upcoming project.
Parts bike - 90 VTR250 - 22k+, "maintained" by idiots, but mostly complete, no title.
Barbie & Skipper
 
Posts: 32
Joined: Fri Nov 16, 2018 5:12 pm

Re: Fuel coming out of air vent tubes on carbs

Postby squirrelman » Sat Dec 08, 2018 6:28 pm

Barbie & Skipper wrote:
squirrelman wrote:Needle seats don't suffer any real wear, so why replace them $$ ?? for fuel overflow just replace the $6 float needle, not the whole set. with hexhead screws there is some danger of over-tightening and carb damage, which is impossible with stock screws.the float bowl gasket can cheaply be replaced with a -041 standard Viton O-ring. :roll:



Thanks. Do you have the part number and/or a link for the correct float needles?


K&L supply will have them. same needles are used on dozens of bikes, hundreds !
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