2001 Optimax 200 not starting

[bferg61]

Hello. I have a Utopia with a 200 Optimax Merc motor. Ran fine till it just up and died under WOT one day last year. All injectors and plugs are in fine shape. I thought I had an air pressure regulator problem due to while cranking I was getting 70 to 80 psi on the air rail but it dropped to 25 immediately when cranking stopped. Replaced air pressure regulator but still have drop in pressure after cranking.
Replaced battery as it was original and spark is confirmed with inductive timing light.
Looks like time to apply some battery power to hi press fuel pump to see if operational or tear apart the fuel pumping assembly and check for obstructions.
Can't figure out why pressure is dropping so fast after cranking.
Diaphragms in fuel regulator and tracker valve were inspected and cleaned.

 

[Double07]

What is the fuel pressure at the fuel rails? the service manula says an air pressure of 79psi +- 2 psi and fuel pressure is 10psi higher than air pressure at the rails (89psi +- 2psi). It looks like your air pressure is getting to 80psi. If air pressure is getting to 80 psi, but fuel pressure at the rails is not getting to 90, then I will look at the fuel regulator and high pressure fuel pump (clean internal screen/filter in the VST).

If you think the air pressure is dropping too quickly and you have already checked the air pressure regulator, I will check the reed valves in the compressor. the compressor has reed valves that allow pressurized air into the rails, but block backflow.

I am asuming you have checked the fuel and air injectors.

 

[bferg61]

I have to squirm a round tire pressure gauge into the area to check fuel pressure. I think I should be able to get it with help. I was also going to unplug 2 of the 3 pumps in the fuel assembly to see if they are working when I turn the key to the on position. Can't tell for sure with them all running at the same time. Do you know if all 3 pumps pressurize or all but the high pressure when the key is turned to on position?

I didn't think of the compressor reeds for the air pressure drop. I will check those. Thanks.

All the fuel injectors look fine, I have had the fuel rails off several times. All 12 ohm out fine and none shorted to ground.

From the way it just all of a sudden died and refuses to start I am suspecting the high pressure fuel pump went. When it died is seemed as though it lost fuel. I have pressure after attempting to start it, but it's only 30 lbs. Have yet to be able to check fuel rail pressure while cranking. I have had the fuel regulator diaphragm and tracker diaphragm out and cleaned and checked them but found no cracks or holes in either of them. Once I get a good check on the fuel rail pressure while cranking reading it will more than likely confirm my suspicion.
Since I will be tearing apart the fuel management system, and this is the first major problem I have had with the boat, should I also replace all the fuel hoses? I was reading someone suggested replacing them every 5 to 8 years.

 

[Double07]

12 ohm?? did you mean 1.2 ohm?
From my manual, the air injectors are suppose to be within 1.3 ± 0.3 ohm, and the fuel injectors are suppose to be within 1.8 ± 0.1 ohm
If you are getting 12 ohm, then I would double-check the injectors. If you have them out, you can run 5V through them, and you should hear them click. There are actually a few contraptions on youtube that shows how you can easily check/clean injectors.
Here is one of them: http://www.youtube.com/watch?v=VFJlTfHyrUk&feature=related
I did something similar too for my injectors. If you decide to check the injectors, I would stick with 5V. I read somewhere that they are driven by 5V from the ECU. I am not sure if that is right or wrong, but I didnt want to find out, so I stuck with 5V. Polarity didnt matter.

You might as well replace the hoses while you are at it. Make sure to use a fuel injector hose with a high enough psi rating and corresponding clamp.
If you are tearing apart the fuel system, one thing to check for is that you have fuel in the VST tank. lack of fuel will indicate issues with the lift pump or the low pressure pump or obstruction in the fuel line. I replaced the metal twist-on fuel filter going into the lift pump with a clear plug-in fuel filter. That way I was able to tell that fuel is getting into the VST. I would also check/clean the metal screen in the VST.

 

[bferg61]

By the number 12 I meant all 12 injectors, 6 fuel and 6 direct. I just did a pressure at the fuel rail while cranking check. After 10 seconds of cranking the pressure got to 75 or maybe 80 psi but no further. I also disconnected all 3 fuel pumps and plugged them in 1 at a time. Turn the key to the run position and the lift pump I know is running cause it is the loudest. The low pressure pump that draws from the VST to the inlet of the high pressure pump felt and sounded like it was working. The high pressure pump was very quiet and I could barely hear it. After a second try of this pump I could hear and feel it working, although I'm not sure if it is working properly as I have no basis of comparison.

Last year when this happened I replaced the vapor separator and the fuel filter in front of the lift pump and also the air filter. Didn't really start working on it till a little while ago.

 

[Double07]

Got it. All 12 injectors ohm out fine.
I think you are right on the high pressure pump. If you are getting the same pressure on both the fuel and air rails, and the fuel ragulator checks out ok, then my guess will also be the high pressure pump.

 

[bferg61]

I am thinking that a complete tear down and cleaning of the fuel pressurizing system. Reassemble with new hoses and hook everything back up and give it a try. If I find that the fuel system is not all that dirty and it does not start then I will replace the HP fuel pump.

Do you know if there have been a lot of the HP pumps go bad?

 

[Double07]

I havent heard of several of them going bad. I have only read of one HP pump change in this forum.
http://www.seadooforum.com/showthread.php?39349-Checking-fuel-pump&highlight=high+pressure+fuel+pump
But I am not sure if this is the same engine as you have.
I am sure you did this already, but you already checked the fuse right?
If you have the VST open for cleaning, you can run the HP pump through 12V to check if it works.

 

[bferg61]

Yes, fuses were the first thing checked. All 3 pumps feel as though they are running.

I'm taking an educated guess that if the 3 pumps are running and the pressure is almost where it needs to be, I now suspect a restriction rather than a blockage somewhere between tank and fuel rails. Most likely I suspect it is the screen in the VST area. Further investigation will soon reveal my cause of not starting. Let me get the fuel pressurizing system out and cleaned and back on and I will let you know if successful or not.

 

[bferg61]

Upon further diagnosis the fuel pressurizing assembly got disassembled. No problems existed in there. The screen on the HP pump was clean. However I noticed not a whole lot of fuel came out when I emptied the VST. All lines and passages to and from the pressure assembly were clear and open. I tried to blow the gas line back to the tank, no flow. I pulled the line off the tank an blew through and it was severely restricted. One blast with the air compressor and it blew the line clean. There is also a check valve the line attaches to at the tank. Gas only flows out but not back in. I put a clear filter up just before the lift pump and filter assembly and turned the key so the pump could prime and no gas in clear filter. Looks as though the lift pump is not lifting. Am going to remove and test. The guys at the auto parts said a lot of people are complaining about the ethenol eating fuel lines and causing these clogs.

 

[Double07]

The clear plastic filter sure makes it easier to see when fuel is going through.
I would recommend you replace all the hoses that you can. In my case, I also replaced the anti syphone valve with a regular barbed connector as I felt that the anti syphone system is a bit restrictive (this was also mentioned in the mercury manual).

It takes a few on/off turns of the key for the gas to travel from the tank to the clear filter, so I would try 3 to 4 times before calling it quits.
If you manually test the lift pump and find it to be ok, but it doesnt work when connected to the system, check the connector. In one of my posts, I mentioned how fixing the connector to the lift pump and changing the check valve solved my fuel problem.

 

[Double07]

I pulled the line off the tank an blew through and it was severely restricted. One blast with the air compressor and it blew the line clean.

I would replace the metal fuel pump attached to the lift pump. If your lines were clogged, chances are that the filter will need replacing. You could replace with a similar filter or put a barbed connector and use a clear inline filter instead.

 

[bferg61]

After I got the engine running in the back yard. All 3 fuel pumps working and a clear gas filter in line before the lift pump filter and pump assembly. Without the filter attached I put the pump in a bowl of water and powered it up. It pumped so I thought it to be good. Reinstall pump and turn key about 6 or 8 times. No gas in the filter. So I cheated and used my hand vacuum pump and brought gas through both filters and reconnected the hose leading into the water separator filter. Gave lift pump 12 volts off the battery till I saw no gas flowing through the filter. Plugged 2 pumps in so the low pressure pump could fill the high pressure pump area. Then plugged all 3 pumps in, turned the key a few times then bled air out of fuel rail a few times till no more air. Turned the key and it fired up. Shut it down, hooked up a water hose and started it back up and let it idle about 5 minutes.

Took it to the river saturday and put it in. Started it up and idled it away from the dock. 200 yards away from the dock I opened it up to get it to plane out. It started to then died. Out of gas, no fuel in the clear filter.

My deduction from all of this is a lift pump that can't keep up with the demands of the other tow pumps. When I was idling it in the back yard the clear filter was full when I vacuum filled the lift pump and had a tiny little corner when it was idling. I say replace the lift pump and some new fuel line.

When I was down at the auto parts getting the filter they said they have seen a lot of ATV's and boats getting clogged fuel lines cause of the ethenol in the fuel eating the lining of the line. They sold me some enzymes to add to the fuel to eliminate this.

With a new lift pump, should it lift fuel from the tank without me priming it? Or should I prime it to make sure it doesn't burn itself up before the fuel gets there? The fuel line connects to a fitting at the tank that has a ball in it that prevents back flow into the tank, only out of the tank. I had it off and it seems to be no restriction of gas flow. Should I replace with just a plain fitting?

 

[Double07]

The pump doesnt need to be primed.
If you re-read my post here in this thread, i think I mentioned a couple of times that my anti-sysphone valve (the fitting with ball in it) could be too restrictive.
You can try running with just a plain fitting and see if it makes a difference before going to buy another lift pump.

 

[bferg61]

Got it. At $140 for a lift pump I will certainly give it a try. I was also going to hook my hand vacuum pump up to the inlet side of my lift pump and see what amount of suction it has. Is this an accurate test? Or should I put a 36 inch hose on the inlet and see if it can draw up through the hose to the pump? If I am not mistaken, the clear gas filter should be partially full at all times during operation under any throttle position.

One nagging question is why is this happening now. I have had this vessel new since 2003 and this is the first time it has ever done this. Is it deposits on the ball that are restricting the flow? The spring should be getting weaker as time goes on.

So if I nix the anti siphon and the lift pump still can't pull gas up to the pressurizing area then the lift pump could still be the problem. Just depends on the reading I get from the test of lift pump. My manual shows normal reading of 1 to 2 psi. with a max of 10 psi.

 

[bferg61]

After removing the lift pump and the line going to the tank, I vacuum tested the whole assy. Found the fuel line to be leaking slowly. Seems as though the ethenol eating at the lining of the fuel line caused it to become air permiable and not hold a vacuum. I also put my vacuum pump on the inlet of the lift pump and powered the pump. The needle did not move. No suction. I got the barbed fitting at the tank off and removed the anti siphon ball out of it. So now I have a guaranteed obstruction free path to the lift pump. Put everything back on the motor and gave battery power to the lift pump. No gas showed in the clear inline filter. So I vacuumed pumped the fuel up and through the lift pump. Gave it power from battery again and it emptied the fuel close to itself but drew no more gas from the tank. I have a new lift pump on order.

I will post results after I install new lift pump and test.

 

[bferg61]

New lift pump installed. Finally drawing fuel from tank. After filling fuel pressurizing system with fuel, cranked motor. After about 8 rotations it fired up. Idled for 20 seconds and shut it down. Doing on the water test this weekend.

 

[bferg61]

Lift pump and fuel hose obstruction were the cause of the problem the whole time. Had the vessel at WOT and many other positions and it ran great. Thanks again to all who replied and steered me in the right path. Another Sea Doo back on the water and running like new.