Question about 1993 Suzuki GSX-R 750 WP

1 Answer

Wont run on prime setting on fuel tap

Help new to biking got gsxr750wp 1993 was running on fuel tap on position told to change it to prime but all it done was cut out after 100 meters (ie loss of power,back fire and pain to start again) now it wont run on pime or on ! what have i done wrong can i sort it or is it a painfull vist to a bike shop?

Posted by on

  • blkninja007 Dec 02, 2008

    I have a 1993 Suzuki GSX-R WP and my problem is that the bike starts and idles fine. But when you go to put in gear and put any kind of load on the throttle it hesitates and trys to cut off. If I take the air filters off the bike it hesitates then kicks a gets up. Unitl you switch gears then it does it all over again. I thinking a new set of carbs will fix this issue. My bike is liquid cooled can you guys tell me what type to get and maybe where I can get a lost cost set?

×

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    Brigadier General:

    An expert that has over 10,000 points.

  • Master
  • 6,966 Answers

Hi,

On most Japanese bikes, the PRI position allows fuel to flow from the tank to the carbs even if the engine is not running. In the ON position, the fuel gate valve would only allow fuel to flow if there is vacuum which of course would mean that the engine is running. There is normally a vacuum hose from the intake manifold of cylinder 1 that leads back to the fuel valve that triggers the internal diaphragm to open the fuel line.

If we are to assume that for some reason the PRI position is blocked, then switching the "fuel tap" to this position would not allow fuel to go down the carbs. Thereafter, the engine used what fuel was left inside the carbs (100 meters) and the engine died. Switching the "fuel tap" back to ON again would not allow fuel to flow down from the tank to the carbs since there is no vacuum and very little vacuum when starting the bike; and the bike would not start, no fuel inside the carbs.

Correct action of course would mean overhauling the "fuel tap" and initially setting it to PRI and then to ON soon as the engine is running on its own. Temporary remedy/workaround would be to manually feed fuel to all the carbs with the use of an external container with rubber hose/fitting. Alternately, you can try spraying starter fluid or car injector cleaner. This should be done with the air cleaner off. A word of caution, in some older bikes I have worked on, this condition would result to an overflow of the carbs soon as the engine starts indicating that the float(s) inside the carbs are sticking.

Hope this be of initial help/idea. Pls post back how things turned up or should you need additional information. Good luck and kind regards. Thank you for using FixYa.

Posted on Nov 11, 2008

  • Ryal702 Oct 13, 2011

    I had the reverse of his problem. Your explaination of how the vacuum system works in a fuel petcock helped me solve this problem. Suffice to say, my original assumption that the hose (that was supposed to connect to the cylinder 1 intake manifold) was just a breather hose.

  • steve l crawford
    steve l crawford Feb 26, 2015

    1996

×

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

2 Answers

The petcock valve on the Bigboy TSR 250. What position must the valve handle be when driving. Please explain the 3 positions on the valve.


Is the tap vacuum operated? There will be a pipe from the carb to the tap if there is, and when the engine is running the vacuum from the carb pulls on a diaphragm and opens the flow.
If this is the case, the 3 positions are "PRIME", "MAIN" and "RESERVE".
Disconnect the pipe from the outlet of the tap, but be prepared for fuel to come out. If it does, then the tap is set in the prime position so move it to another setting to stop it. If it doesn't start flowing then the tap is set to main or reserve.
Main and reserve are self explanatory and are standard on most bikes, but prime is not on as many. Never ride on prime as this just allows fuel to flow freely and is only used to start a long standing bike or one that has been run to empty. It does what it says and primes the carb. Once running switch over immediately to main or reserve.

Oct 22, 2015 | Motorcycles

1 Answer

Which way to turn the reserve tank switch on


There are 3 positions (as you probably know). Reserve, on and prime. Under normal conditions with a properly working fuel tap, prime is the by-pass that allows fuel to flow through without the engine running. On and reserve will only allow fuel to pass when the engine is running (uses vacuum from the carb).
  • PRIME has the handle facing down
  • ON is when it is facing the front
  • RESERVE when it faces the rear.
Do not leave the tap in the prime position EVER as this allows the fuel to fill the carb and with the engine running or attempting to start will cause hydrolock that will bend the pistons con-rods. Only use it to fill the carb with fuel and turn it to on or reserve as soon as you can.
If the bike runs using the prime position but will not run when on or reserve, then you may have a vacuum problem or a dodgy tap......assuming you have fuel that is.
Hope that helps.

Sep 14, 2015 | kawasaki KLE 500 Motorcycles

1 Answer

I have fuel coming out of oil breather screw when i rev bike px 125


whats fuel doing in oil, if its an inlet to recycle oil fumes then remeber bikes are vacuum action fuel taps so fuel would only overflow while running or if there a prime position on tap(some bikes). if your sure this aint the problem then hows fuel getting there. if crank seals gone and the oil has burnt it could take in fuel. you should notice lack of gear oil if this is the case.

Feb 14, 2013 | Motorcycles

1 Answer

I hav a gsf 600 bandit year2000 WITH A FUEL STARVATION PROBLEM the bike will run if fuel tap is in prime position but if you turn it to on position the fuel supply stops same on reserve HELP!


Chack fuel filter, maybe it's dirty, plugged or incorrectly positioned. It hase arrow which shows fuel flow direction. Maybe someone put it up side down.

Dec 13, 2010 | 2000 Suzuki GSF 600 S Bandit

1 Answer

Where is the prime position on the fuel on a GSX 750 fn


THIS IS QUITE EASILY RECTIFIED, REMOVE THE FUEL LINE FROM THE TAP,SLOWLY TURN THE TAP FROM 1 DIRECTION TO THE OTHER, WHEN FUEL FLOWS READILY FROM THE OUTLET ON THE TAP, NOTE THE POSITION ON THE TAP AS FUEL WILL ONLY FLOW WHEN IN PRIME POSITION. {VACUME TYPE TAP REQUIRES ENGINE TO RUN FOR FUEL TAP TO OPEN, WHEN NOT RUNNING FUEL SHOULD ONLY EXIT THE TAP IN PRIME POSITION). REASON FOR FUEL FLOW WHILE NOT RUNING WITH TAP IN ANY POSITION, COULD BE DIAPRAM FAILURE IN TAP.

Dec 04, 2010 | 1998 Suzuki GSX 750 F (Katana)

1 Answer

Hi, On the fuel tap what is the Prime position function.


You have a vacuum operated fuel tap. It should have 'on' , 'res' and 'prime'.
In the prime position fuel will always flow from the tank. In the other positions the engine must be running to allow fuel to flow. If the bike has been standing for a few days, fuel will evaporate from the carbs and the bike can be difficult to start. By switching to prime for a minute, the carbs are replenished and starting should be easy. Dont forget to return the tap to on or reserve once started.

Sep 06, 2010 | 1997 Suzuki GSF 1200 Bandit S

1 Answer

My 1996 750 Katana runs but it will only run with


You may need to rebuild the fuel tap with a new diaphram kit.

The fuel tap has a small rubber diaphram and plunger, which can go hard, stick closed , or wear out and get a hole.
Also check the vacumn hose than opperates the tap is in good condition
Pri bypasses the vacumn opperated fuel tap, sometimes this can cause the carbs to flood or have higher than normal float levels..
Running it on prime can also cause the carbs to flood fuel into the engine filling the sump, which then s ucks fuel vapour through the crank breather into the airbox, and then through the carbs causing over rich.
If this has happened you also need to change the oil and fit a new air filter element

Jul 17, 2010 | 1996 Suzuki GSX 750 F (Katana)

4 Answers

What position on the petcock is on off or res on a 93 katana gsx600f


There is no OFF, you have RES toward front , ON is all the way down, and prime toward back, PRI is used when it has been sitting for awhile. RES and ON wont let gas out unless bike is runnig. There is a vac hose on back of petcock that lets ON and RES work it must be connected..

May 29, 2010 | 1993 Suzuki GSX 600 F (Katana)

1 Answer

My bike will only run on prime position


Rebuild or replace the fuel petcock.

May 16, 2010 | 1993 Suzuki GSX-R 750 WP

2 Answers

Just bought a 2007 Honda Shadow VT 600 and had fuel pump off for transport. Got home, forgot to turn fuel line on, and started the bike. It ran for a few seconds, then died. Tried to start it a few more...


is the tank fawcett workin--is the pump producing-is there a hindrence in the line--is batt at 12v-and gettin spark to pistons-chec plug cables and whole ignition for operation and good connections

Apr 14, 2010 | 2001 Honda VT 600 C Shadow

Not finding what you are looking for?
1993 Suzuki GSX-R 750 WP Logo

1,138 people viewed this question

Ask a Question

Usually answered in minutes!

Top Suzuki Experts

yadayada
yadayada

Level 3 Expert

61249 Answers

Arnie Burke
Arnie Burke

Level 3 Expert

4481 Answers

Ed Nelson
Ed Nelson

Level 2 Expert

149 Answers

Are you a Suzuki Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...