2003 ox66 hot restart.

[robnik12]

New to the forum, thanks for the help.

I have now experienced this about 4 times on different trips out, never twice in one trip. After running engine, typically at slow speed, we shut it off for about an hour or so(resturant). When we return we start engine but it sputters out immediately. Check primer and find it empty. Reprime and try again and still wont start. The last time this happened I was ready with a fuel pressure guage. Found no fuel pressure. Was ready to tow it in and tried one last time and it cranks and runs great. Very hard to reproduce this problem. Also I would have bet on third occasion I had fuel pressure indicated by relieving the shrader valve at the vst. Was originally thinking main relay. Disconnected relay today and found engine would not turn over, so thats not it. Was thinking fuel pump resistor and tested it, found .6 ohm which is close. Also disconnected it and turn key to run and found pump would run without resistor, did not try starting though. Also , the engine is very hot as it has been run then sits in the sun while it is turned off for an hour or so. If its a cold egnine it always start fine. Also, I will need to replace the primer as it allows fuel to return to tank when I sit. Any recommendations on a good primer, I have only use yamaha primers but they dont last.

[rodbolt17]

dude, get off the primer it has not failed.
you have enough fuel in the vst to start and run about 10 min(idle) even if you disconnected the fuel line.

now we do have to address the fact the fuel pump wont turn on at key on and run.
at key on and any engine speed above 1200 RPM the resistor is not used.

at key on you should have 12V at the pump red/yellow to ground.

if so turn the key off,go from pump blue to ground.
turn the key on,it should come up to 12v then rapidly fall to almost 0v when the pump runs,after 3-5 seconds it should come back to about 12v.
the ECU controls the pump ground path.
the main relay supplies it with 12v+.

[robnik12]

Thanks for the reply.

Hope to test soon. Also found loose pos battery connection. 10.5v before and 11.5 v after. Also getting highspeed stall and instant recover, figure battery may also cause that.

Primer bulb will not reprime after siphoning back unless I remove hose and use finger, so at least another reason to replace.

[rodbolt17]

why bother with it?
once the VST is full it remains that way.
the lift pumps will take over once the engine is started.
all the primer does is fill the VST after a service.