Figured I'd let you guys have a crack at this - 05 GTi LE RFI won't run

[kevinz]

With the riding season approaching, I figured I probably should try and fix one of my skis from last year. I also have a Polaris and Kawasaki I can ride while I wrench on this.

Ski in question is a 2005 GTi LE RFI. Has 200-something hours, but I installed a new engine and rebuilt the pump. Electronically, everything works.

The ski always had sort of a rough idle. However, once you hit the throttle it was smooth as silk and ran great. Also, usually after riding it you had to open the throttle a hair to get it to start. That might be an important clue. Last year, while out on a lovely river ride, the ski just quit running. It was as if the engine was shut off. It cranks, but won't start. Diagnostics so far have revealed that fuel is getting to the injectors, they are firing, and I do have spark. Rotary valve appears to be in time and does spin. MPEM does pulse the injectors on and off as verified with a test light.

My first impulse is to blame the injectors and/or fuel pump. No maintenance light or any warning indicators present. When I installed the engine, I replaced both strainer filters in the fuel pump assembly. The pump does come on when the key is inserted on the post and while cranking.

Any thoughts on this? Would like to fix it as it's a nice ski and will be a good cruiser in the summer.

 

[mikidymac]

What's the compression? You need 3 things, fuel, compression and spark and you have verified the spark and fuel.

 

[kevinz]

compression is 150 per cylinder. That was the first thing I checked, and forgot to mention it.

 

[etemplet]

Fuel pump pressure sounds logical. I doubt both injectors would go out at the same time.

 

[kevinz]

Fuel pump pressure is a common theme I keep coming across. Even thought I put new filters in it, who knows what shape the pump is in. Ski had like 250 hours on it. The engine was full of water and hull full of oil. Now it has an engine with less than 20 hours on it and it's all cleaned out. I know from my automotive mechanic days, the human eye can not tell the difference between 20 PSI and 50PSI in a fuel injection system.

Also, when I was tinkering with it a couple months ago, it seemed like it may have been flooding with fuel; an injection system with low pressure can certainly do that if memory serves because the fuel doesn't have the pressure behind it to atomize properly; thus it wont burn. I do remember seeing the injectors each spray fuel when I removed the fuel rail and placed it in a large jug.

I do not have a fuel pressure gauge. I may be able to make one, however. Are there any kind of plans to make on on this site?

 

[mikidymac]

Weak spark could also be essentially blowing out under compression also.

 

[kevinz]

If that was happening, would my spark tester still light up?

 

[etemplet]

What if the injectors are dribbling as in "not sealing properly" ? That will keep the engine flooded. If you are getting spark at the right time... something should fire unless you are getting no fuel or too much fuel. I send mine to a guy in Florida. For less than $50 I get the injectors spot on and ready. I too have a ski I'd like to Test the fuel pressure. I have a pressure tester and a spare fuel line that I can equip with a "T" to read pressure. I just need the proper fitting..

This is what my filters looked like. Yikes !!

 

[kevinz]

Injectors dribbling has been another thought I've had. I do want to send my injectors to that guy in Florida. However even thought I do that I'm not sure that will make it run. What's hanging me up is the fact that this ski literally just shut off while riding. Everything electrical works great so it was like someone just hit the start stop button. And now it wont start despite appearing to have everything it needs, but I dont know if the spark or fuel pressure is good enough to run it

 

[funsummerahead]

Sounds like fuel. Probably just not enough to run. Same thing happened to my friends DI a week after I replaced his fuel pump. The fuel line on the pump itself split so it would get just a little fuel and sometimes idle and sometimes not. I'd check the pressure from the tank and if that's good I'd also check the return line to the tank as it may be a bad. I know the DI has more parts than the RFI in the fuel system rail but if you have good spark and compression it has to be the fuel system. Could also be your TPS which a dealer has to reset so the pressure test I'd do first.

 

[etemplet]

I plan on getting into the logic of the computer system on the RFI and probably the DI's as well. I wonder if the idle setting is the default for the computer where the ski should at least start up? We need to devise a hot fast and cheap method of checking fuel pressure. I've been thinking of taking fuel rail and rigging it to accept a gauge. So it would be a simple plug in. All we need is a fitting with an adapter though. I thought I saw something that would work at Harbor Freight but didn't want to chance buying the kit. What is the fuel pressure range on the RFI?

 

[kevinz]

I thought I read in the manual around 52-55 with engine running. I think that BRP really screwed everyone when they released RFI and DI systems with no way to access codes without their proprietary scanner. The automotive world had simple ways to pull codes with the early EFI systems utilizing OBD1 and many of those systems used Bosch components. OBD2 introduced a standard port to plug a scanner into to get information. I can't think of any reason BRP couldn't have done this, for example being able to jump 2 terminals in a diagnostic connector and have the gauge show codes.

Also why they thought a schrader valve on a fuel rail to check fuel system pressure isn't important is beyond me. In any EFI system fuel pressure is usually one of the first basic things to check. A simple schrader valve to screw a generic fuel system pressure gauge onto would have been a smart idea.

 

[mikidymac]

I thought I read in the manual around 52-55 with engine running. I think that BRP really screwed everyone when they released RFI and DI systems with no way to access codes without their proprietary scanner. The automotive world had simple ways to pull codes with the early EFI systems utilizing OBD1 and many of those systems used Bosch components. OBD2 introduced a standard port to plug a scanner into to get information. I can't think of any reason BRP couldn't have done this, for example being able to jump 2 terminals in a diagnostic connector and have the gauge show codes.

Also why they thought a schrader valve on a fuel rail to check fuel system pressure isn't important is beyond me. In any EFI system fuel pressure is usually one of the first basic things to check. A simple schrader valve to screw a generic fuel system pressure gauge onto would have been a smart idea.

Because then you are forced to take it to a dealer for service. Mo Money!

 

[funsummerahead]

When I checked the DI and RFI I did the cheapest thing but it worked. I cut the main fuel line coming out of the tank and with a couple hoses and clamps I checked the pressure with my cylinder compression gauge. Probably not the best way to do it but it worked good all 3 - 4 times and my gauge is still good too. The DI has a return line from the fuel rail but I don't think the RFI does. I checked the pressure by cutting the main fuel line and rigging up the cylinder compression gauge straight to it and then also checked it again by putting a T on it so the gauge and the injectors where both hooked up so see if they were leaking. When checking with the gauge just install the DESS KEY and it will power the fuel pump for a second. Plug it in and pull it out several times and check the pressure. After that I installed a large car fuel filter to reconnect the line again. You need to get the right sized filter for high fuel pressure and micron size but I forget what it is. The RFI should have a fuel pressure of 56 - 60 PSI. You could also just use a piece of brass or aluminum tubing with a couple hose clamps but a fuel filter of the right size I figured would be best.

 

[kevinz]

A small update...injectors have been sent in for service. That might not fix it, but it was going to be done regardless. New fuel pump is also pretty cheap so I'm going to throw one in for peace of mind

 

[mikidymac]

Don’t buy the aftermarket fuel pumps as they are junk.

 

[funsummerahead]

You can get the Bosch on ebay for $40. That's what I used on the DI 3 years ago and the RFI 2 years ago and they're still good.

 

[kevinz]

You can get the Bosch on ebay for $40. That's what I used on the DI 3 years ago and the RFI 2 years ago and they're still good.

Do you mean fuel pump or injectors

 

[funsummerahead]

Bosch Fuel Pump. I got lucky and never had to test the fuel injectors on either ski as I figured out the fuel pumps were bad first by checking the pressure. Both fuel pumps DID work, but they were low on pressure. The DI also had a bad fuel pressure regulator on the fuel rail as well. I think the RFI pressure regulator is on the top of the fuel tank - built in. There is a kit on there from the same seller for $95 with the fuel pump and a pressure regulator but their listing doesn't show what it fits. They say to check their compatibility chart but I can't find it in either listing. These may not be the right ones as the listings read 3 bar which is about 43 psi which is too low. The pump only listing does have the Sea Doo part number though - MARINE KIT 1 BOSCH FUEL PUMP FOR SEADOO 270600003 FOR GTX RFI

 

[Fern]

So would that be the plug to drain the oil from the crankshaft right

 

[mikidymac]

So would that be the plug to drain the oil from the crankshaft right

No don’t touch that plug.

 

[funsummerahead]

So would that be the plug to drain the oil from the crankshaft right

No. It's too far away from the rotary valve bath cavity. Looks like a drain to empty the crank case from water ingestion and I'm pretty sure there's another one on the other side. Not all engines have them. What year and model is your ski?
Why would you want to drain the oil?

 

[Fern]

No. It's too far away from the rotary valve bath cavity. Looks like a drain to empty the crank case from water ingestion and I'm pretty sure there's another one on the other side. Not all engines have them. What year and model is your ski?
Why would you want to drain the oil?

I've been told it has the wrong oil

 

[Fern]

No. It's too far away from the rotary valve bath cavity. Looks like a drain to empty the crank case from water ingestion and I'm pretty sure there's another one on the other side. Not all engines have them. What year and model is your ski?
Why would you want to drain the oil?

Its a 94 sea doo spx going to replace the oil has the wrong one in it

 

[funsummerahead]

That's not good. There's not an oil drain to do that so it will be a little bit of a mess no matter what. How much oil is in the tank?