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Hrkdrivr
07-12-2013, 11:50 PM
Last Friday the engine was surging with a boarder on the rope and RPM around 2,800. Surges were +/- 200-300 rpm. You could hear it and feel it. It happened both on cruise control and when using manual throttle control. It happened only after we had been driving around for about an hour.

I read the Fuel Pump 101 thread and some others. I got a fuel pressure gauge and took some readings Wednesday.

Video here: http://www.youtube.com/watch?v=eOCJs9Tz_6g

Air temp was 90 F. Oil pressure was 50 psi at idle, 60 psi in gear/running. Engine water temp steady at 160 F. L-18 engine.

I have not pulled the pump/filter/regulator yet.

Fuel pressure looks OK (?) at idle, fluctuates badly in gear up to about 3,000 rpm, then smooths out all the way up to WOT. (Gotta love the sound of the engine on launch/at full throttle!) The video doesn't do the fluctuations justice. When viewed naked-eye, i.e., not through the camera, the needle was a blur, almost impossible to see.

Is this normal? Is this a pump problem? Regulator? Is the regulator replaceable?

mikeg205
07-13-2013, 12:57 PM
When was the fuel filter changed last? could be fuel pump? IMO

Hrkdrivr
07-16-2013, 10:56 PM
When was the fuel filter changed last? could be fuel pump? IMO

I just pulled the fuel module. I replaced the pump with a new Airtex. New filter should be here tomorrow and I'll be able to reinstall everything and check it out.

No comments on what the fuel pressure is doing at mid-range RPM?

I hope it's not a regulator problem...I don't know if it's replaceable.

mikeg205
07-17-2013, 09:06 AM
I do not think the inconsistent fuel pressure readings are not regular. I bet all is good after new pump and filter... not sure what the pressure readings should be on your boat...

skitilldark
07-30-2013, 10:31 AM
My cousin had this issue on a 96 205. His was surging mainly on idle though and would go away eventually. His turned out to be a cracked sleeve surrounding a sensor that was'nt bad enough to get the sensor to throw a code but bad enough to have the sensor attempt to adjust the idle. Not sure if this is the same thing, but thought I would throw it in the ring anyway.

Mark rsa2au
08-02-2013, 09:12 PM
Hrkdrivr

Did you resolve this? what was the final issue? I thought it should be the regulator but I may have a similar issue but at higher RPM?

Hrkdrivr
08-04-2013, 04:47 PM
Hrkdrivr

Did you resolve this? what was the final issue? I thought it should be the regulator but I may have a similar issue but at higher RPM?

Mark

After replacing the pump, the issue is NOT resolved. Sigh. Fuel pressures are erratic in the mid-RPM ranges. After a couple hours of pulling boarders, the engine starts to surge when trying to hold around 2800 RPM, both on cruise control and manual throttle control. At this point the hole shot suffers too. It's like something starts acting up when it gets hot.

I think you're right, I think it's the regulator.

Has anyone removed a regulator from their pump module? Can you just pull it out of the grommet/out the top of the module? Anybody know the right replacement part/number?

blackhawk
05-27-2014, 03:17 PM
Hrkdrivr - Did this turn out to be your fuel pressure regulator? If yes, can you replace just the regulator or did you have to buy the entire module?