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The RFI (Rotax Fuel Injection ) Spot

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griz400

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well, i been getting pm's about the rfi's, wich is ok, but im going to (re-do) this thread and maybe with help of all of you rfi owners, we can fix all of our problems -- my name is jeff, and i have been through a few trials and problems, but, the rfi, along with a friend of mines year 2000 model, we have been pretty trouble free as of late -- so welcome all, and please input all of your data !!!!
 
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Here is a good, not to expensive, sorta needed maintance that should be done, possible every couple of years, is changing your fuel filters -- (2 strainers ) .... IN tank filters, just by removing your fuel pump assy, by removing your glove box compartment (4 retainers) comes right out, and there is fuel pump module, remove all retaining nuts, main fuel line, vent line, and wiring connector, then remove pump assy,KGrHqJHJEEE-njyti9OBPwCUcvnZ60_58.jpgKGrHqRHJDE-lM93hHvBPwCUlWnDQ60_58.jpg and take off bottom plate, then you have 2 fuel stainers (they are called) -- (advanced auto parts sells them ) 1 - part # fs242 -- approx 15.00 - 2 - part # fs220 -- approx 10.00 ---- also, if you want to change the bosch fuel pump at this point, they also have the original bosch fuel pump and part # is 20770241 -- approx price is 93.00, and then, take and remove all the fuel in tank, wipe clean with a shop towel, and re-assemble --
**** this is our fuel system repairs (along with 2 fuel injectors) , there is no problems with gray fuel lines, and carb overhauls, etc ****
and DONT put any fuel inj cleaner, etc in the fuel, (just clean 87 octane is sufficient)
 
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Thanks for this post. I've been having problems with my 2000 GSX RFI and ordered a new fuel pump last week. I pulled the fuel module out of the tank, how do you get the old pump out? I don't want to screw anything up.
 
 
Fuel injectors, -- the rfi has 2, quite simple to replace, and i found a good place (inexpensive) so, not really worth sending out to clean and test, believe me, i lost 2 motors cause of a defective fuel injector, simply disconnect fuel line, has 2 10 mm bolts that hold fuel rail on, remove the rail, disengage clips that hold injectors to fuel rail, then remove from rail, clean rail with cleaner (like carb spray or t/body cleaner), air dry with compressed air, then install clips to the injectors first, then lubricate with silicone spray, or vaseline, push into place and you will see clips engage on fuel rail, then re-install rail to motor, (put some vaseline on bottom o-rings also http://www.fiveomotorsport.com/0280150845-65lb
source for fuel injectors i found fuel pressure can change drastically from just checking it at idle -- i spent like 58.00 ea. shipped to my door in 3 days -- TAKE BOSCH PART NUMBER OFF THE TOP OF YOUR EXISTING INJECTORS , then give the number to them, use the bosch number, cause the brp number is a bosch injector in a brp bag and they sell for like 225.00 ea. -- same part, different box -- lol......
 
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Flushing after use, the rfi engines basically the same, start eng, hose on, hose off, shut off eng, --- but, the rfi's have a magneto cooler and a lower crankcase cooler (both they actually call them heat exchangers ), but check at rear of hull when flushing, expecially when at the beach in sand, cause they can clog up, so stick you fingers up into where the exhaust comes out (like 4 inches) and you will feel a pretty solid hard stream of water coming out when on the hose, if not, take off the upper hose on front mag cover cooler, blow compressed air in it, this will come through it, through the lower cooler, and out the fitting at rear of exhaust -- here is a pic of a clogged one !

367.jpg
 
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Basic fuel system operation -- RFI motors have 5 sensors that provide information to the fuel injection system. 1) throttle position sensor. 2) water temp. 3) air temp. 4) air pressure. 5) crankshaft position sensor. If one of these sensors malfunctions the watercraft will be put into limp mode and will be rev-limited to get the operator back to land.
RFI fuel systems. The fuel system consists of .1) the fuel pump. 2) the fuel pressure regulator. 3) the fuel filter. 4) the fuel level sensor. 5) the fuel injector. Every thing listed here except the fuel injector is located in the fuel pump assembly which is located in the fuel tank. Fuel pressure should be tested while the watercraft is under a load, due to the fact that the fuel pressure can change drastically from just checking it at idle. The correct fuel pressure should be 56-60 psi.
 
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Charging system -- a little picky with the rfi cause you are operating a fuel injection system, so, needs a little more amps, more so than a carbed ski, this unit has a 3 phase delta wound stator with a 270 watt capacity, with a rectifier than converts ac voltage to dc voltage to charge battery at like a 5 amp rate.

testing stator at 3 yellow wires with engine running at approx 3500 rpms you shold have between 25-40 vac, and at battery you should have like 13.5 ish volts at 3500 rpms, if you experience over 15 volts at battery - replace rectifier
 
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failsafe feature -- some think is a fuel issue -- but amps are needed to operate fuel system, RFI computers have a function that will sense the battery voltage. If battery voltage drops below 8.9 volts for 30 seconds the motor will rev-limit to 4480 rpms, If voltage drops below 7 volts it will shut down the engine completely.
sorta the importance of a spare rectifier, a couple extra fuses, and a well maintained battery, i always keep a battery mainainer hooked up to ski when not in use, the charging system is protected by 2 fuses, 1 15 amp fuse mounted on the mpem, and 1 20 amp fuse in the rear electrical box.
 
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Rectifiers -- guess this was one of the main flaws with the rfi's, i bought a couple different ones, the one i used for a year now isnt the one everyone seems to like (the 4 tech rectifier ) but, this one http://www.newjetskiparts.com/product_info.php?cPath=524_531_749&products_id=70969

paid 69.00 , i also have the beefed up one, but never really used it yet,

here it is, my buddy uses it on his 2000 model - http://www.osdparts.com/index.php?main_page=product_free_shipping_info&cPath=6&products_id=8

they both seem to work, i guess the original one had its problems
 
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Oil pump and filter and oil, best thing i can say about this is just keep it all clean, i use nothing but brp full synthetic (yellow jug) ole yeller, lol, and just keep it all clean
 
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FYI to all RFI owners,

You CANNOT do away with the oil injection system and go to premix on a RFI engine. Doing so will cause severe damage to the cases and rotary valve. :cheers:
 
correct dennis, being that its fuel injected, the oil and air comes in on one side of motor, creating all oil properties, and fuel is injected on other side of motor, so eliminating oil pump is not possible !!
also, just adjust cable so that both marks on oil pump line up, i tried to give it more oil, doesnt do anything, here is a pic --
87fd664d.jpg005.jpg

and also use the 3/32 tygon hoses as you can see, most failures are due to like a split old hose, or one that has cracked and fell off, the oil pump hardly ever fail, these hoses i buy at a big lawnmower repair shop here in town
 
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Wiring connectors -- remember when working on ski, the aps (air press sensor) and the tps (throttle position sensor) are both 3 way plugs that can be plugged in either sensor, also, the rave valve solenoid and the injector plugs are the same style of 2 way connectors, that can be plugged in either way.... and, always dielectic grease on all of your wiring connectors.
 
Wiring connectors -- remember when working on ski, the aps (air press sensor) and the tps (throttle position sensor) are both 3 way plugs that can be plugged in either sensor, also, the rave valve solenoid and the injector plugs are the same style of 2 way connectors, that can be plugged in either way.... and, always dielectric grease on all of your wiring connectors.

Jeff, Is this only on FI motors?
What will or won't happen if someone mixes up the switches.
 
not sure on other skis what plugs can be mixed up, but you would have no throttle responce or a no start condition, and with injector plug it would miss like h*** or no start,
 
Two quick questions.

I've heard jumping from another battery is the easiest way to fry your rectifier. However, I tend to keep a maintainer on the battery when not in use. Will charging the battery at a low rate (700mah if I remember) hurt the rectifier? I've always unpluged the rectifier from the battery, but a loose connection in the plug make it a pain. My other thought was just wire a charging switch on the red line.

My other question, regarding the gtx rfi's in particular, is has anyone found a better impeller for them? My current one works good, I'm just looking for anything to make it better :).
 
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