Excalibur 330 Fuel System Troubleshooting & Info

[CurtisC]

I recently purchased a 2008 SN 196 with the Excalibur 343. I assume this discussion about the fuel system also applies to this PCM engine. The boat has intermittent issues and will sputter and die. We replaced the distributor cap & rotor and spark plugs, which all looked good. I Serviced the FCC, installed a new filter in it, fuel in the FCC looked clean with no water. The ECM shows only around 100 hours when it is connected to Diacom. Previous error code was a bad crankshaft position sensor, which has now been replaced. Ran good after changing that and then, Same problem occurred again with no new error codes, our mechanic suggested replacing the fuel pump relay, so we did. We thought it was fixed and the boat ran great for 1 outing. Next time out same problem, engine sputters, dies and would not restart, finally restarted after about 1 hour. It ran great today & then died again after about 4 miles of free skiing, would not restart and we had to be towed back in. I can hear the fuel pump when the ignition is turned on, but would not restart. I suspect either the low pressure or the high pressure fuel pump. I have not found or replaced the inline filter from the tank to the FCC, but the way it just dies under power does not seem like it would be the inline filter. How do you diagnose the low pressure fuel pump? The manual shows fuel pressure should be 57-62 psi at the fuel rail manifold at WOT. So do I need to get a fuel pressure gauge and see if I get the specified pressure running under load at WOT? Thank you for any advice about this issue.

[Brucetheshark]

Hi Curtis, the 2006 SN196 do not have an in-line hose filter despite others here stating they do. Perhaps some boats previous owners installed one, but it’s not needed. There is a filter at the low pressure pump that serves the same purpose of filtering larger debris, it’s a pinky finger size mesh versus the large paper filter in the FCC for the high pressure pump. There’s pics in the manual, and part is available from Nautique parts. You can rent for free a pressure gauge from most auto parts stores, only requires a deposit. Hopefully you’ve already learned that the safety kill switch lanyard can be very deceiving, looking like it’s clipped on fully, when it’s not. It only cuts off the fuel pump, not spark or starter. Good luck, keep us updated on your progress. ~Bruce

[JayG80]

Bruce is correct. https://nautiqueparts.com/fuel-pre-filter-kit/

[CurtisC]

Hi Curtis, the SN196 do not have an in-line hose filter despite others here stating they do. Perhaps some boats previous owners installed one, but it’s not needed. There is a filter at the low pressure pump that serves the same purpose of filtering larger debris, it’s a pinky finger size mesh versus the large paper filter in the FCC for the high pressure pump. There’s pics in the manual, and part is available from Nautique parts. You can rent for free a pressure gauge from most auto parts stores, only requires a deposit. Hopefully you’ve already learned that the safety kill switch lanyard can be very deceiving, looking like it’s clipped on fully, when it’s not. It only cuts off the fuel pump, not spark or starter. Good luck, keep us updated on your progress. ~Bruce

Hi Bruce, thanks for the response. I Ordered a fuel pump test gauge kit on Amazon last night since I figure I might be testing this again in the future. I still don’t know if the gauge will show me which pump is bad if the pressure is not up to the specified 57-62 psi. If the pressure is low I plan to check the FCC canister and if it is full then, I would conclude the low pressure pump is working and the problem must be the high pressure pump inside the canister. Any thoughts on that? I’m so ready to be able to use this boat with out having to worry about it leaving me stranded on the lake.

Regarding the in-line filter I had looked for it previously, and now I will not look for it. I was going on the posts I read and it shows up in the PCM manual.

The very 1st time I went out on this boat, the plastic kill switch clip failed/broke while on the lake and I had to hold in the switch with my thumb while driving it back to the ramp. The new lanyard/clip worked fine , but I did not know that it kills power to the fuel pump, so I will look at that real close, maybe bench test it.

I read with interest your post about the gasoline smell when taking the cover off the boat. Thanks for the detailed post with pics on the fix at the fuel tank lines & fittings. I have the same smell with my boat. Did you narrow this down using the sniffer you talked about? And where do you get one of those? Thanks for your comments.

[Brucetheshark]

Hi Bruce, thanks for the response. I Ordered a fuel pump test gauge kit on Amazon last night since I figure I might be testing this again in the future. I still don’t know if the gauge will show me which pump is bad if the pressure is not up to the specified 57-62 psi. If the pressure is low I plan to check the FCC canister and if it is full then, I would conclude the low pressure pump is working and the problem must be the high pressure pump inside the canister. Any thoughts on that? I’m so ready to be able to use this boat with out having to worry about it leaving me stranded on the lake.

Regarding the in-line filter I had looked for it previously, and now I will not look for it. I was going on the posts I read and it shows up in the PCM manual.

The very 1st time I went out on this boat, the plastic kill switch clip failed/broke while on the lake and I had to hold in the switch with my thumb while driving it back to the ramp. The new lanyard/clip worked fine , but I did not know that it kills power to the fuel pump, so I will look at that real close, maybe bench test it.

I read with interest your post about the gasoline smell when taking the cover off the boat. Thanks for the detailed post with pics on the fix at the fuel tank lines & fittings. I have the same smell with my boat. Did you narrow this down using the sniffer you talked about? And where do you get one of those? Thanks for your comments.

Hi Curtis, The pressure gauge will measure the high pressure pump in the FCC, so if the pressure is low, the HP pump is bad. I think you’re correct, if the pressure is okay and FCC is not full, the issue may be the LP pump. Note: the HP pumps rely on being submerged in fuel to cool the pump motor, so if your LP pump is intermittent, the lack of fuel in the FCC may cause the HP pump to fail from overheating. I imagine this could also possibly happen if the LP pump filter were heavily clogged.

On my previous boat a 2001 PS190, I had to replace the HP pump 3 times, and found it at auto stores for $50 with warranty (which I used twice), vs the entire Mastercraft FCC for $800. The MC FCC design is poor and doesn’t keep the pump submerged if the tank is <1/4 full. Those small pumps are very common in modern cars and boats. You should be able to look up your HP pump p/n (part number) assuming it’s stamped on the pump. It may also be on the NP website. For reference, I took the HP Pump filter to NAPA auto parts store a few weeks ago and surprisingly to me, he found a NAPA version cross referencing the NP p/n, so should work for the HP pump.

Regarding the fuel odor, sealing the 8 tank fittings didn’t completely remove the odor, but it’s significantly less. Curiously it smells different now. I know my boat’s previous owner ignored all the stickers and used ethanol fuel, so I may have to replace the hoses and/or reseal the FCC fittings (ugh). I bought the sniffer from Home Depot ~$25, but didn’t get any alerts for the boat hoses, tank fittings or FCC fittings. It alerts if held near an open fuel filler cap.

Another fuel issue; following the ethanol issue from my previous owner, I only use 100% gas (Rec fuel), w/o ethanol. I drain the tank over the winter and plug the tank vent to keep out moisture. In May when I launched the boat, I added 100% gas, but got a knock warning on the Tach LCD. I drained the tank thoroughly, tested the fuel by adding rain water, and it turned gold, meaning ethanol and probably old. So I’m going to talk to the owner of the (small local) gas station. I did the same test, same day on 100% gas from BP and it looked perfectly separated and clear (see photo). A-I may not be perfect, but here’s it’s answer to "what causes fuel with ethanol to turn gold when exposed to moisture?” A-I: "Ethanol-blended fuel can turn gold when exposed to moisture due to the formation of corrosion products, particularly from metals like copper and brass in the fuel system. This reaction occurs as ethanol is hygroscopic, meaning it absorbs water, which can lead to corrosion and the release of metallic ions that change the color of the fuel”.

My photo below: Left is small local station, right is BP, both fuel + water.
~Bruce

[CurtisC]

Update on this issue. I got the fuel pressure test gauge kit, hooked it up and ran the boat on a water hose. Fuel pressure started at 59 psi and went to 62 as the engine warmed up. I guessed it would start up normally & knew the problem only would show up after it had been running for a while. As I waited for the problem to show up I checked the kill switch and found no issues with it. I started listening closely to the low pressure fuel pump and noticed it getting louder and hotter as the test proceeded. I also started feeling the fuel pump relay and noted it was getting hotter and hotter as the LP fuel pump got louder. After about 40 minutes run time the LP fuel pump was louder & the relay were both really hot and finally it happened. I heard the engine start to slow and miss, the fuel pressure dropped to below 30 and the engine died. I tried to restart and could hear the HP pump trying but it could only fluctuate the pressure from 20-40 and of course it didn’t start. I only tried it once as I didn’t want to keep running the HP pump with low fuel level in the canister. The LP pump was really hot.

I ordered a new LP fuel pump and new relay today. The FCC does not have the pre-filter kit at the LP pump that was mentioned. So I will either get one of those housings with the replaceable screen or install an inline filter. I will update after I get the new LP fuel pump and relay installed. Thanks Bruce and Jay for your responses. Bruce I am planning to switch over to ethanol free fuel since It’s available here. Great info about that issue.

[Brucetheshark]

Update on this issue. I got the fuel pressure test gauge kit, hooked it up and ran the boat on a water hose. Fuel pressure started at 59 psi and went to 62 as the engine warmed up. I guessed it would start up normally & knew the problem only would show up after it had been running for a while. As I waited for the problem to show up I checked the kill switch and found no issues with it. I started listening closely to the low pressure fuel pump and noticed it getting louder and hotter as the test proceeded. I also started feeling the fuel pump relay and noted it was getting hotter and hotter as the LP fuel pump got louder. After about 40 minutes run time the LP fuel pump was louder & the relay were both really hot and finally it happened. I heard the engine start to slow and miss, the fuel pressure dropped to below 30 and the engine died. I tried to restart and could hear the HP pump trying but it could only fluctuate the pressure from 20-40 and of course it didn’t start. I only tried it once as I didn’t want to keep running the HP pump with low fuel level in the canister. The LP pump was really hot.

I ordered a new LP fuel pump and new relay today. The FCC does not have the pre-filter kit at the LP pump that was mentioned. So I will either get one of those housings with the replaceable screen or install an inline filter. I will update after I get the new LP fuel pump and relay installed. Thanks Bruce and Jay for your responses. Bruce I am planning to switch over to ethanol free fuel since It’s available here. Great info about that issue.

Hi Curtis, Sounds like you found the problem, good to hear!! The PCM manual states to test at WOT which you did, it also states ‘under load’. Good to hear ‘under load’ may not be required to diagnose the issue since testing while running the boat (hole shot) is more tricky.

Pics below are from 2006 PCM manual:




a 2006 boat should have a LP Pump filter, check the PCM manual photo attached. The filter fitting is hidden by the pretty gloss black paint.




I have winterization steps and wrench sizes in my phone notes app; here are my LP Pump filter notes:
5/16 nut driver for hose clamp.
Insert 10mm bolt with threads cut off to plug fuel line.
9/16 Socket with 6" extension to remove LoPres Pump Mtg Bolts, to make space to clear motor mount while unscrewing filter cap & 90 degree hose barb.
1-1/8” Open wrench for filter cap.
Needle nose to pull out filter.
Big toothpick to remove Washer Seal from cap.


I ordered an Amazon fuel pressure gauge arriving today to address my knock sensor warning.

Question: Does your boat have the original Faria gauges with the LCD window in the tach and speedo? I’m curious if you have a knock sensor warning due to the low fuel pressure. Since I have new filters and fuel, and can’t even hear a knock at idle using a stethoscope, I may have a fuel pressure issue also. The knock warning only triggers after a hole shot getting a slalom skier up. Not during a medium hard acceleration or long (one hour) test drive.
~Bruce

[JayG80]

That’s a helpful write up Bruce. I’ll add that the pretty gloss black paint you described can make the virgin filter removal difficult. My wrench slipped when the paint finally released and I cut my fingers on a neighboring hose clamp free tail. I ordered a bag of 1/2” and 5/16” clamp end guards the next day. https://a.co/d/0j606X85

[CurtisC]

Thanks for the response. There is a lot to learn about these boats and I appreciate the experience and knowledge from you guys! The PCM manual for this 2008 year model shows some different information about several things. My FCC looks different than what yours showed. Here is the fuel system diagram from the manual:

So it has the LP fuel pump mounted on the side of the FCC canister and does not have the serviceable pre filter that yours has. The fuel line comes directly into the bottom of the LP pump. Here is a photo of mine.


And the information regarding Ethanol fuels has changed to basically , it's OK but with warnings: So I can see why there is confusion around this issue, but the same warnings are there about corrosion, moisture, and potential for damage to fuel system parts. I still agree with Bruce and I intend to switch to Ethanol free fuel only.

[CurtisC]

Lastly my gauges were replaced already when I bought the boat, due to the known Gateway issues. I only have the "Check Engine" light between the speedometer and the Zero off gauges. So when it comes to the knock sensors, I assume it would only give me the check engine light, and I am not seeing that when I accelerate, and I don't hear any knock.

I still plan to test the fuel pressure when I go out on the lake to see if it will maintain 57-62 psi at Wide open throttle. The fuel pressure gauge I got has a long enough hose to lay it towards the from of the engine and I think I can carefully open the engine cover and look at it going down the lake,

[JayG80]

Looks like the changed the LPP on FCC mid-year 2007

Per Skidim.com:

Low-Pressure Fuel Pump RA080036A

Fits: Mid 2007 S/N 473065 up EX343, 5.0L, 6.0L. New style FCC feed pump. This pump is now silver not black.

[Brucetheshark]

Looks like the changed the LPP on FCC mid-year 2007

Per Skidim.com:

Low-Pressure Fuel Pump RA080036A

Fits: Mid 2007 S/N 473065 up EX343, 5.0L, 6.0L. New style FCC feed pump. This pump is now silver not black.

Good info Curtis & Jay, I edited my post above to reflect “2006”.
I’m pretty sure during my Knock sensor DTC that the red light didn’t light up, but it was a bright day, I’ll check again next chance. I believe the red light is fed from the MEFI-4, not the Gateway box, based on the Gateway and MEFI wire harness circuit lists. MEFI-4 list shows “MIL”.

[jpwhit]

There are two generations of FCC designs. The later version has the low pressure pump mounted on the side of the FCC. Some Nautique boats with the later FCC design have a disposable fuel filter in the line between the tank and the FCC low pressure pump. Don’t know why they didn’t include that on all boat models.

https://nautiqueparts.com/fuel-filte...-pcm-r080024a/

On a 200 for example, the filter above is in the fuel line under the back floor panel behind the engine. If you boat doesn’t have that filter. I’d add one.

I know ethanol fuel is a controversial topic with boats. On fuel injected boats that are designed to be compatible with ethanol fuel, which means all the fuel system seals are viton or some other ethanol safe material, I use ethanol fuel during the season because it helps keep water out of the system. Where ethanol fuels don’t do well is stability over time. So I switch to non-ethanol fuel before any storage for more than a month or so. I’m involved with multiple ski clubs and we put over a thousand cumulative hours on boats every year and this has proven a reliable approach over all those hours for years now.

Where I always use non-ethanol fuels is small lawn equipment engines with carburetors.