Problem with Fuel and Air Hoses

[Darksik]

Hi guys i have a 2009 ninja 250R, my problem is the next:

The bike only work when the petcock in "PRI" position, when i put in "ON", the bike dies because the fuel don't go to the carbs, i was watching a image, when shows what lines got the carbs, and my bike is not connected like the picture.




Somebody can please help me if exist some picture or video to connect right the fuel and air hoses, because i read if my bike still running on "PRI" the carbs could be damaged


Also my bike is the US Version, not the california version.

[DannoXYZ]

Hi and welcome!

Originally Posted by Darksik

Hi guys i have a 2009 ninja 250R, my problem is the next:

The bike only work when the petcock in "PRI" position, when i put in "ON", the bike dies because the fuel don't go to the carbs, i was watching a image, when shows what lines got the carbs, and my bike is not connected like the picture.

Somebody can please help me if exist some picture or video to connect right the fuel and air hoses, because i read if my bike still running on "PRI" the carbs could be damaged

Carbs won't be damaged in PRI position if float-valves are working. However, if they aren't, fuel can drip through carbs and into engine when bike is parked. You can hydrolock pistons and destroy an engine! Like snap con-rod and send it out side of engine-block!

1. First, test petcock for proper operation. Set to ON position and it should NOT flow any fuel. Apply vacuum of at least 10-in.Hg to vacuum nipple. Does fuel flow out of petcock? If not, R&R petcock as necessary

2. next if petcock confirmed operational, make sure hose labeled "vacuum hose to petcock" is intact with no cracks or leaks. Verify it's actually connected to petcock and clamped securely on both ends. If this doesn't work, use vacuum-T and measure vacuum in that hose. Should be at least 10-in.Hg at idle to keep petcock open and flowing fuel.

3. if you don't have sufficient vacuum in hose labeled "vacuum hose to petcock" to keep petcock open, then you've got leak in carbs. Verify all hoses are connected as shown in picture. I think the only difference with non-CA model is you don't have the plastic T in the middle of that hose section.


Fast and efficient low-cost troubleshooting requires measuring and coming up with numerical data. Those numbers will help track down problem area so you can R&R just the bad part. All used parts should be tested and measured. Otherwise, you can just swap out petcock, vacuum hoses and carbs for brand-new units from dealer and problem should be fixed.

[Darksik]

Originally Posted by JacRyann

Hi and welcome!

Carbs won't be damaged in PRI position if float-valves are working. However, if they aren't, fuel can drip through carbs and into engine when bike is parked. You can hydrolock pistons and destroy an engine! Like snap con-rod and send it out side of engine-block!

1. First, test petcock for proper operation. Set to ON position and it should NOT flow any fuel. Apply vacuum of at least 10-in.Hg to vacuum nipple. Does fuel flow out of petcock? If not, R&R petcock as necessary

2. next if petcock confirmed operational, make sure hose labeled "vacuum hose to petcock" is intact with no cracks or leaks. Verify it's actually connected to petcock and clamped securely on both ends. If this doesn't work, use vacuum-T and measure vacuum in that hose. Should be at least 10-in.Hg at idle to keep petcock open and flowing fuel.

3. if you don't have sufficient vacuum in hose labeled "vacuum hose to petcock" to keep petcock open, then you've got leak in carbs. Verify all hoses are connected as shown in picture. I think the only difference with non-CA model is you don't have the plastic T in the middle of that hose section.


Fast and efficient low-cost troubleshooting requires measuring and coming up with numerical data. Those numbers will help track down problem area so you can R&R just the bad part. All used parts should be tested and measured. Otherwise, you can just swap out petcock, vacuum hoses and carbs for brand-new units from dealer and problem should be fixed.

Hi, and thanks for the welcome, i don't understand what means "R&R".

The petcock don't leak any fuel outside the petcock, when i put the petcock in "ON" the gas stoped to flow the fuel, also does not flow while the motorcycle is turned on, The only hose that is connected like the picture is the "Fuel Inlet line From Petcock"

The vaccum from the petcock is connected to the T but the T is onlu connected to the Coasting Enricher from the right side.

Also one hose is connected to the "Carb Sync adjuster screw"

That is the level of my hoses problems

[DannoXYZ]

Originally Posted by Darksik

Hi, and thanks for the welcome, i don't understand what means "R&R".

Sorry, R&R = repair or replace

The petcock don't leak any fuel outside the petcock, when i put the petcock in "ON" the gas stoped to flow the fuel, also does not flow while the motorcycle is turned on,

That is correct. The ONLY time petcock should flow in ON position is when vacuum is applied. Connect hose to diaphragm port on petcock and manually apply vacuum greater than 10-in.Hg. We NEED to know if petcock is 100% functional before proceeding. You can try sucking on diaphragm hose instead of using vacuum-pump. But you have no idea what vacuum level you're achieving and risk sucking in lungful of petrol if diaphragm is torn.

The only hose that is connected like the picture is the "Fuel Inlet line From Petcock"

The vaccum from the petcock is connected to the T but the T is onlu connected to the Coasting Enricher from the right side.

Also one hose is connected to the "Carb Sync adjuster screw"

YIKES! No hose should be connected to Carb Sync Adjuster Screw!!!

Here's what you do:

1. test petcock for functionality, replace if not functional

2. remove ALL hoses, both ends of each

3. inspect ALL hoses for cracks & tears, replace if bad

4. reconnect ALL hoses according to diagram. One at a time, do one end, then other, clamp both ends. Then do next hose, one end, then other, until ALL hoses are routed according to diagram.


Do you have long hose that connects to California Emissions Fitting T that runs to front of engine?
Do you have a round vacuum valve hanging from frame between spark-plug boots?

[maverick9611]

https://www.ninjette.org/forums/showthread.php?t=44054

[Darksik]

Originally Posted by JacRyann

Sorry, R&R = repair or replace

YIKES! No hose should be connected to Carb Sync Adjuster Screw!!!

Here's what you do:

1. test petcock for functionality, replace if not functional

2. remove ALL hoses, both ends of each

3. inspect ALL hoses for cracks & tears, replace if bad

4. reconnect ALL hoses according to diagram. One at a time, do one end, then other, clamp both ends. Then do next hose, one end, then other, until ALL hoses are routed according to diagram.


Do you have long hose that connects to California Emissions Fitting T that runs to front of engine?
Do you have a round vacuum valve hanging from frame between spark-plug boots?

1. I test the petcock, only flow the fuel, when is on "PRI" and when is "ON" the fuel stop.

2. if i got time, and be sure how are connected the hoses, tomorrow i can do that.

3. I already checked and the hoses are good, they don't have cracks.

4. Now i remember, the vacuum hose from the petcock is more narrow than the vacuum hose from the carbs. :/ maybe could work if i put a hose clamp using the vacuum hose from the carb


Yes i have the long hose and the T, but i think one is connected to the right coaster enricher (as how shows the picture), another is connected to the vacuum from the petcock, and another is connected to the vacuum switch valve

Yes the vacuum valve is there hanging.

[DannoXYZ]

Originally Posted by Darksik

1. I test the petcock, only flow the fuel, when is on "PRI" and when is "ON" the fuel stop.

This is only 1/2 test. The other test is to make petcock flow in ON position. Apply vacuum to smaller port on petcock and fuel MUST flow in ON position. If it does not, petcock is bad. Replace petcock with new working unit.

[Darksik]

Originally Posted by JacRyann

This is only 1/2 test. The other test is to make petcock flow in ON position. Apply vacuum to smaller port on petcock and fuel MUST flow in ON position. If it does not, petcock is bad. Replace petcock with new working unit.

The fuel must flow even when the bike still off?

[DannoXYZ]

Originally Posted by Darksik

The fuel must flow even when the bike still off?

Yes, we are testing only the petcock. It must flow when vacuum is applied to smaller port. You can use hand-held vacuum pump to create vacuum. Petcock should flow. If not, it is bad.

Right now, we don't know if problem is due to bad petcock or bad hoses. Need to test one at a time.

[Darksik]

Originally Posted by JacRyann

Yes, we are testing only the petcock. It must flow when vacuum is applied to smaller port. You can use hand-held vacuum pump to create vacuum. Petcock should flow. If not, it is bad.

Right now, we don't know if problem is due to bad petcock or bad hoses. Need to test one at a time.

sorry for this dumb question but, can work if i seal a hose connected to the vacuum of the petcock with my finger?

[DannoXYZ]

Originally Posted by Darksik

sorry for this dumb question but, can work if i seal a hose connected to the vacuum of the petcock with my finger?

No because there will be no vacuum in hose. You need to find or borrow one of these.

[ducatiman]

one o' these will suffice