2000 ox66 lp fuel pump replacement

[hammertimeee]

What are the systems of a bad lp fuel pump on a ox66. How often should they be replaced

[99yam40]

I would think you need to inspect/test them every year or when you have a motor problem and replace as needed

[hammertimeee]

I would think you need to inspect/test them every year or when you have a motor problem and replace as needed

Can you recommend a good aftermarket pump that works. My ox66 takes three pumps and Yamaha pumps are about $50 each... I have no problems using aftermarket pumps, as long as they are proven to work..

[99yam40]

Sorry, no recommendations for anything but OEM

[amahaork]

Can you recommend a good aftermarket pump that workhave no problems using aftermarket pumps, as long as they are proven to work..

They don't.

[pstephens46]

What are the systems of a bad lp fuel pump on a ox66. How often should they be replaced

Systems? Symptoms? What is going on with the motor?

What motor is it?

[boscoe99]

Go over to the Yamaha section at bass boats central and do a search for the replacement of the two/three mechanical lift pumps with one electric fuel pump. Fully documented. Seems to be working very well.

I had a Mercury EFI model. Similar to the OX66 EFI models from Yamaha. It used one lift pump. Never failed in the 600 hours I put on the motor before I sold it. I have never fully understood Yamaha needing to have two or three of the buggers.

[hammertimeee]

Systems? Symptoms? What is going on with the motor?

What motor is it?

250HP ox66 on back of a 232 GW Gulf Stream

I have a hesitation from 2000 to 3000 RPM. I recently remove the VCM filter and cleand it. Very little dirt inside of the screen. I bought new plugs and will change them out tomorrow. I was just wondering if the lp pumps will cause a hesitation in mid rpm.. I am only hitting 4900 rpm @33 mph. This motor should be hitting 5500 or so.. Could th 02 senser be causing this pronlem???

[pstephens46]

Well I believe the general test for a failing LP pump would be to pump the primer bulb at time of problem. Bulb takes over the job of pulling fuel from tank to motor. Wonder if this is the case? Have you tried pumping the primer when this happens?

If it was my motor I wouldn't want to buy parts that may not fix the problem.

[hammertimeee]

Well I believe the general test for a failing LP pump would be to pump the primer bulb at time of problem. Bulb takes over the job of pulling fuel from tank to motor. Wonder if this is the case? Have you tried pumping the primer when this happens?

If it was my motor I wouldn't want to buy parts that may not fix the problem.

I havent tried pumping the bulb while the motor is running.. I did notice the bulb never gets hard but she always starts right up. I'll look into changing that out first before the pumps

[pstephens46]

If you are having problems such as running, then stalling, pump the ball to see if that helps. That may point towards a lp fuel pump issue. Not suggesting you change it without checking things out first. No sense in buying parts you may not need.

[jfbetz01]

If your primer bulb will not firm up when you squeeze it, it is likely a LP lift pump issue. The fact that you can keep squeezing the bulb suggests fuel is being pushed past the one of the LP pumps into the cylinder. Pull 3 plugs out from one bank of cylinders, squeeze the primer bulb 10 or 15 times, pull your lanyard so the engine wont start, and crank the engine. Whichever spark plug hole fuel shoots out of will correlate to the bad LP pump.

[hammertimeee]

no spark on #3 cylinder, ox66 250HP

when i removed my plugs yesterday I noticed the #3 plug was not firing. I did a spark test on all wires, and the #3 was the only wire not giving my a spark..

I plan on switching the #3 pulse coil to see if it sparks on another coil.

If by chance I still dont get a spark out of a bew pulse coil on #3, what else should I be checking for .ie: stator, ECU?? or a lose wire from the ECU to the pulse coil?

[hammertimeee]

If your primer bulb will not firm up when you squeeze it, it is likely a LP lift pump issue. The fact that you can keep squeezing the bulb suggests fuel is being pushed past the one of the LP pumps into the cylinder. Pull 3 plugs out from one bank of cylinders, squeeze the primer bulb 10 or 15 times, pull your lanyard so the engine wont start, and crank the engine. Whichever spark plug hole fuel shoots out of will correlate to the bad LP pump.

Thank you, I absolutely will try that test. I have to check to see why I am not getting spark from my #3 wire. I plan on swapping out my pulser coil to see if that works. Fingers crossed!!

[99yam40]

It would be best to check peak voltages or ohms.

pluser coils are under the flywheel