View Full Version : Engine Runs smoothly but won't achieve full power
06-02-2006, 09:17 PM
I've got a 2000 Prostar 195 with the 310HP Indmar 350. Boat & Engine have 250 hours.
The engine starts fine, accelerates smoothly, but the boat has lost all top end power over the last week. When I push the throttle up to 100% the engine accelerates smoothly, but never passes 3000 RPM. I can't get a slalom skier out of the water. Max speed empty is 30 MPH. The engine isn't missing at all. Strangely, if I back off the throttle a little bit I can coax the engine up to 3300 RPM and get a tad more speed.
Thought I just needed a tune up and replaced the distributor cap/rotor/ignition wires/spark plugs. Didn't help. Any ideas?
06-02-2006, 10:34 PM
I experienced the same thing with my 96 Maristar with LT1. It was a fuel delivery problem - fuel filter/pump issue.
You have a fuel problem. It could be at the pickup in the tank, the fuel filter or the pump but I would check the first two before anything else. Look on the motor and see if the fuel pump is mounted on it. If it is, remove the inlet line and clean the screen on the pump.
If the tank has run dry and someone tried to restart repeatedly, the pump's impeller may be bad. Check the fuel pressure at key ON, idle, 2000RPM and WOT.
east tx skier
06-02-2006, 11:10 PM
In addition to fuel delivery, make sure the flame arrestor is cleaned regularly.
06-02-2006, 11:22 PM
Looks like the fuel pump is located in the tank for this boat. I opened up the back storage cover (Prostar 195) and I can hear the pump whinning while on the water at idle. I can't hear anything with the storage cover closed, so I don't know if this noise is normal or not.
I can't seem to find the fuel filter, unless its imbedded in the fuel sending unit thats in the fuel tank. Looks like the fuel lines run non stop from the top of the gas tank to the EFI set up.
The fuel sending unit on this boat is a Carter with two numbers. 71-299S and CGB 98-002. My internet search hasn't turned up squat for either number. Any ideas?
OK, I didn't know if you got one of the earlier ones or not. The filter is on the pump (at the bottom) and the filter should be available from a dealer.
Use the 71-299S number- the CGB is a Coast Guard number.
06-03-2006, 12:23 AM
Will I have to get the filter from a MC Dealer, or will I be able to find it at the autoparts store? Also on the 2000 Prostar is there a second filter? Thanks for all your help, just read through a ton of other fuel pump/filter posts....do you ever get tired of repeating yourself? :-)
I repeat myself when under stress, I repeat myself when under stress, I repeat myself when under stress,......
MC dealer only as far as I know.
06-04-2006, 06:38 PM
Changed the fuel filter and the Prostar is up running at 100%. Thanks for the help guys. I will add that removing the fuel tank pump was a %&$#@. The original owner had done a number on the fuel pump unit during the last fuel filter change. The casing and pump were in several pieces when I got to them. I was able to put everything back together, but there's probably a new pump in my near future.
Short lesson here: The fuel tank has to be moved forward in the 2000 Prostar 195 to get the fuel pump unit out of the tank because of clearance issues. Apparently the last time the fuel pump/filter was changed they just mashed it in.
On another note, any tricks to getting the filter on this pump? I went at it gently, because the old filter had been mashed in the process and I didn't want to repeat. Its a friction fit, but it took me an hour of pressing and encouraging before I got it to the point where it was secured. I'm sure JimN is going to tell me that there's a special $2 tool that makes it a snap. :)
I got mine at the Dollar Store, sorry. Actually, when I was working at the dealerships, the filter wasn't available separately so I don't remember replacing one without the pump.
Will, MYMC, BAWS- little help here?