twin 496's....full throttle to get on plane...all's well, shortly after plane, port motor drops rpm from 3500 to 2000...then 1000 the back to 2000 etc, ...If I feather throttle on port motor to around 2400 and keep it there, she purrs fine, anything above 2400 and she drops rpm drastically and pops every now and then.

If motor is in netural, rpm will hold steady at 4000 without a hiccup. BTW, no 'warning beeps' whatsoever whether in gear or not.

any sugguestions? sounds anf acts like it is fuel related.

on top of that, I get back to the launch and as I am pulling up to the dock, I loose a hydraulic steering hose and loose all steering....was an interesting day on the water. Luckily I have three teenage boys to help wrestle the boat onto the trailer.

Thanks

Happy 4th guys!!

it sounds to me like that motor is running out of fuel pressure for whatever reason. i would expect your fuel press gage to be fluctuating and low when this happens... if its injected, then it could be one of several things. i had a 502 do this and, of all things, it turned out to be one bad injector that was going to ground and shutting off the others on that circuit.... but that was pretty weird... ide look at fuel pressure first.

I would think it's fuel pressure. There is a small screen at the pump inlet, that may well be where your trouble is at.

Boost pump is going. Shortly it won't even idle. Its located on the starboard side. Depending on what year it is it's right behind the water separator. I've had three go out over the last three years from bad gas. I thnk if it sicks up any gunk or water it fries. Easy way to check is put a fuel pressure gauge on the fuel rail by connecting to the to the shrader valve. Fuel pressure should remain in the 38-42 psi range. If it starts to drop off you know it was the boost pump. In this age of ethanol fuels I would change the separator at every oil change, and once or twice right after the winter. Also start using Startron and Pri-G additives tohelp keep it stable.

Another thing I've had issues with is injectors clogging. I now pop mine out once a year and tap them out on the intake manifold. All kinds of crud comes out. Then I blast them with elctrical contact cleaner (plastic safe) and pop them back in. It's real easy to do. I have yet to find any film whatsoever on the boost pump intake screens.

thanks all. . .

before I could do anything, I had to get my steering resloved otherwise I could not boat anyway. Being that I was out of town boating over the 4th, there was nothing open on the 4th to even try and get parts. Rode the jet skis that day and Saturday morning headed to the nearest NAPA store where I was lucky to find a store owner who has been in business for 40+ years. I brought in my old hose and he said I will make you a new one in 15 minutes. Put new hose on and steering was fixed.

Now onto the fuel boost pump. Pulled that off and found a little bit of gunk inside, cleaned and re-installed. Launched and headed out for a day of boating. Problem solved.

I will be replacing all of the 4 ram hoses and will keep the one NAPA made me as a spare. Anyone with full hydraulic steering should always carry a spare. One bad hose will require a tow in. It was a cheap hose and a cheap fix.