Help Fuel check and cut valve

[A7RXY]

I have been on to Mazda and they tell me this valve is no longer avalible.
 Its the valve with a float in it and is found on the underside near the fuel filter and pump. I think it could be partly blocked as I have replaced both the filter and pump, also had the carb rebuilt.

[Ian65]

Dibs,
sorry to see that you\'re still having problems.
I don\'t know if you\'ve seen the following site which troubleshoots the Nikki carb and fuel delivery but is well worth a look...
 
http://www.sterlingmetalworks.com/the_nikki_carburetor.htm
 
Cheers,
 
Ian

[A7RXY]

Cheers Ian, I have seen it, I\'ll try to get the old valve off and test it and take it from there, just wondering if I could bypass it.

   Dibs

[David Nock (RIP)]

Hi Dibs, This is a post I sent to a guy called Nigel (who didn\'t reply) about testing his fuel pump system. The figures are taken from the Mazda workshop manual.

"Welcome Nigel. To test your fuel pump, disconnect the larger fuel delivery pipe at the carburetor. (smaller one is return to tank on a loop system). With the pipe emptying (CAREFULLY) into a container it should deliver fuel at a rate of 1.1 litres a minute. Also with this pipe plugged into a pressure guage it should deliver about 4 bar.

Above the fuel pump, attached in the rear wheel arch of the body, is a check valve in the return line, though I\'ve never known these to fail.

That leaves the pump itself, the filter, which you\'ve changed, clogged lines or stuck needle valve (gummed up??) in the carb.

Good luck. David."

Have you tested for adequate  fuel delivery at the carb? If yes and it\'s deficient then I would say it should be OK to repeat the test with the cut and check bypassed. Sterling\'s write up suggests it\'s for roll over reasons and that seems right. If you test with the car stationary then that should be double OK.

[David Nock (RIP)]

Dibs,
sorry to see that you\'re still having problems.
I don\'t know if you\'ve seen the following site which troubleshoots the Nikki carb and fuel delivery but is well worth a look...
 
http://www.sterlingmetalworks.com/the_nikki_carburetor.htm
 
Cheers,
 
Ian

Ian Good stuff that guide, I\'ve printed for future reference. Thanks.

[David Nock (RIP)]

Dibs, by the way, there is a PICK UP FILTER IN THE TANK - On the end of the dip tube. Possibly clogged with tank debris after standing? again back to the delivery test?

[A7RXY]

I think the problem is that is eaiser to keep changing things and not testing, so it looks like a testing time is ahead........

[David Nock (RIP)]

I think the problem is that is eaiser to keep changing things and not testing, so it looks like a testing time is ahead........

Yes, I know how you feel. :2Mad

[David Nock (RIP)]

I have got the manual down off the shelf to double check and it actually says do pressure test before doing the volume test. (Makes sense).
Pressure is correct if it is in the range 3.7psi to 4.7psi. Volume delivery should be as above, 1.1litres into a graduated container in 1 minute. Both tests at the main fuel input connection to the carb.
Best of luck.