OX66 225 Does NOT like to run

[tom976]

The other day I was going out, engine sounded a bit rough. 300 feet away from the dock, engine dies. If I tried to restart, it runs for a second and dies.
Eventually it would even start up anymore, just turns over.

Here's what I did so far.
I checked the plugs, look good, cleaned them a bit, they seem fine.
A took off the noise silencer in the front of the motor and sprayed some carb cleaner in there. Fires right up and dies when no more carb cleaner avail.

So I check the VST pump (fires up for a few seconds and bring the fuel pressure up) I open the canister and cleaned it out with some more carb cleaner. The screen on the filter was a little dirty but not too bad. When I hold it to the light, I can see through it.

Put it all back together and same starting problem.

I checked the fuel pressure regulator screen, a little dirty, cleaned it out too. Same problem.

I have 3 brand new lower pressure pumps, swapped them all out and still same problem. (primer bulb gets hard when fully pressurized)

I removed the fuel rail to check the injector screens (had them cleaned this year, they still look good)

The last thing I did was put on a fuel pressure gauge on the regulator. While it did get pressure I am not sure if its enough. (real crappy gauge so I am not sure of it accuracy) It does show that it builds pressure and keeps it up there. not sure if its enough pressure or too much.

When I first put the key in and start it, it will run for a secord or two and die. Afterwards it wont do much else but turn over. If it shut it off for and let it pressurise again, it will for for a second or at least try to start.

Sort of sounds like when it first creates pressure with the electrical pump its just enough to run. From there its not making enough. Does the internal electrical pump even run when the motor is running? Some people say yes, others say not, the three low pressure pumps take over.

So I am somewhat thinking about the pressue regulator. Anyone know how to test it on an ox66? Any other ideas???

HELP
Tom

[jb123]

need to get a gauge that works correctly and ensure you have a constant 35 lbs @ schrader

[tom976]

Granted, I know I need a new one. I have a harbor freight not too far from me. I would get a better one but there arent too many places that sell better ones locally. (sears isnt too far but they dont show anything online)

If pressure is right on, what's next? On engine fuel filter was replaced earlier this year as well as the water/fuel seperator.

Thanks
Tom

[jb123]

dont think itll be on... as you gave it fuel and it ran.. yes? you stopped spraying and it stopped ?
most every parts stores will have gauges

[tom976]

Ok, I will see about getting a new one. What's the next step if the fuel pressure is good?

If it dips below 35 I presume their isnt enough pressure to maintain enough fuel through the injectors?

[99yam40]

Look for air leaks, restrictions, etc. that would cause pressure drop

[tom976]

I went back down today.... Pressure is right on and holding steady at 36-40.
Checked for any fuel leaks, none.

Starts for a few seconds and then dies. Doesnt matter if it throttles etc. Just starts and dies.

[jb123]

when the motor dies does the pressure stay up or drop down
check amp draw @ pump

[tom976]

Well I stopped by again. Pressure is holding steady. When I start it, it goes to 36 and thats it. If I spray a little starter fluid in there and have it run for a few seconds it'll bring the pressure a bit higher.

I put a spark tester on one plug and its igniting like it should.

I tested the amp draw at the pump when it primes and it was at 3.7 amps.
(I know that 5 amps trips the computer to shutdown the fuel injection)

Tom

[tom976]

The pressure holds steady after the pump stops.

Thoughts?

[jb123]

you put a tester on one plug.... need to test all

[99yam40]

You are loosing fuel or spark.
you need to find out which one.
Testing while problem occurs is a must and getting the peak voltage readings would be better than just spark

If you have good spark on all
and you have proper fuel pressure, did you test fuel rail pressure?
then you are either not getting a signal to fire the injectors or maybe injector screens are plugged.

Could it be too much fuel pressure

[tom976]

jb123, I tested all the plugs. All appear to be firing ok.

If I spray stater or carb cleaner, the motor runs till it runs out of fuel.

Pressure from the test port on top of the fuel regulator is right on. (36 lbs)

Spark is good, fuel pressure is there. Highest it went to is 38 or 39.

I am thinking of using a noid light on the injectors to see if there is a pulse.

Not sure if the diagnostic test light will help.... Any idea on how much the cable costs or which one i'd need???

Thanks
Tom

[Dave Joyner]

jb123, I tested all the plugs. All appear to be firing ok.

If I spray stater or carb cleaner, the motor runs till it runs out of fuel.

Pressure from the test port on top of the fuel regulator is right on. (36 lbs)

Spark is good, fuel pressure is there. Highest it went to is 38 or 39.

I am thinking of using a noid light on the injectors to see if there is a pulse.

Not sure if the diagnostic test light will help.... Any idea on how much the cable costs or which one i'd need???

Thanks
Tom

the winky blinky tool does not diagnose fuel system problems costs about $95. probably worthwhile to have if you are going to perform your own maintenance. Sounds like the fuel pressure is not the problem. Previous posts seem to lead to plugged screens in the VST or injectors from fuel impurity/ethanol. Let me know what you find. I am batteling fuel pressure dropping off once the engine starts as VST pump voltage drops to 6.0vdc, until it exceed 1200 rpm then all normal. No replys from any of the forums. Maybe your solution will help me. Good Luck!!

[tom976]

If the voltage drops to 6 volts, I would check the resistor on top of the engine.
Some people were saying the 9 volts on the initial prime stage is ok and then 12 volts when its running normally. Not sure if that is 100% correct. Mine primes at 12 and stays at 12 when cranking.