17 Scarab twin 250 port engine turns over, no start P0340, sensor replaced

[cmckenn]

I have read every post I could find and trying everything recommended before posting here. Purchased a 2017 Scarab 255 a month ago. First day out, both engines fired right up. Check engine light on P301 (didn't realize at this time I could scroll and see multiple codes). Full throttle and felt a slight misfire but completely went away after a few seconds and ran perfect all day long afterwards (check engine light stayed on). Second trip out, backed boat into water and port side engine would not start after numerous attempts. It would turn over but would not crank. Starboard engine fired up no problem every time. Read recommendation on here when I got home and saw a post about the relay. I swapped both relays from the starboard fuse box to the port fuse box and still same issue on port, no issue on starboard. I read another post about the kill safety switch. I pulled the cord attempted to fire both engines and got a loud beep and wrench (I believe this happen when trying to fire both engines, but unsure for reasons later). Pushed the button in with finger and immediately port engine fired up. Tried it several more times with zero issues. Fast forward 2 days.... carried the boat back out. Backed it into water, starboard fires right up. Port giving me problems. After many attempts it finally fires up but is running horrible. No power, will not go over 2k rpms, feels like cylinders misfiring. Check engine light still on from first outing, but i discovered I can scroll through multiple codes and discovered multiple cylinder misfiring and P0340. Camshaft Position Sensor. This made sense from my experience in automotives as to why the cylinders were misfiring. Fast forward 2 days and a rushed part to get boat fixed for trip this weekend. Purchased Noco Genius on board battery charger to make sure batteries were fully charged and good, rush delivered Camshaft position sensor and installed this evening thinking all would be great for the upcoming trip. Batteries fully charged, all connections checked, new sensor installed... Port engine will turn but refuses to crank. Starboard, fires right up. Here is what I have done since then with no resolve.....

- Rechecked all fuses and swapped relays
- Removed safety kill switch and attempted to start (starboard engine crank attempt causes loud beep and wrench, port clicks, but no beep or wrench. Not sure now if it beeped on the first day or attempt as mentioned above).
- Pressed safety kill button with finger as first time but still just turns no crank, starboard perfect.
- Switched wiring harness from starboard to port on fuel pumps and neither engine would fire off. (not sure if wiring and firing from electrical affected this)
- Removed fuel hose from injectors on port side (bad side), switched key on and fuel immediately began flowing into bucket.
- Broke fuel line quick connect in this process so unable to perform any other test until finding part tomorrow.

I am at a loss and have a family boating trip planned this weekend that is not looking hopeful. My thought process at this point is: Camshaft sensor replaced and good, batteries good and charged, fuel coming from tank up to fuel rail, all fuses good, relays good. I have not replaced or tested the spark plugs or coils and will tomorrow (assuming I find fuel line connect), but I can't see how bad spark plugs or a bad coil would cause a "no start" but fully understand a rough idle/run. I am at a loss and maybe I'm being optimistic or hopeful for the weekend trip, but this has to be something simple. My plan tomorrow assuming I find connection for fuel line is to purchase new plugs and pull spark plugs with coils to check spark is getting to each. Any help will be Greatly Appreciated... Not only by me but the kids looking forward to a weekend on the water.

 

[zipper]

@Luc Lafreniere may have some advise for the fix. Code p0340

 

[Luc Lafreniere]

Yeah, step 1, plugs. Lots of your symptoms not to mention the error code literally points to that. EVEN if it isn't the principle cause, it IS an issue based on the code and rough idle. If you get a P0300 through P0303 code (all spark plug related/misfires), just replace them with new plugs. People try to save a few dollars and spend days troubleshooting because they didn't start with the plugs. It's quick, cheap and rules those out immediately.

With the camshaft sensor replacement, that rules that out as well. Spark, air, fuel. Air is almost never an issue in these boats. Spark could be plugs, ignition coils, or wiring of course. Fuel, assuming you fix that broken fuel line issue, then of course it's always possible the fuel is bad. Is it old?

 

[cmckenn]

Thank you so much for the quick response. I will definitely start with plugs when I find quick connect for fuel rail. I am new to Scarab and we live in central Mississippi. I am a little taken back that parts are hard to find or even locate. For instance, the quick connect that broke is Norma PA6 -GF30 but there are tons of different types and I can't find anything to match. I thought SeaDoo dealer would have part since engine is the same, but nope. Thank you again. I will let you know what the outcome is.

 

[Luc Lafreniere]

SOME parts are the same as Sea-Doo, but many parts are not. BRP makes parts for both Sea-Doo and Scarab. But they are not necessarily the same for many different reasons. Sadly, there is no part equivalency lookup between the two.

I highly recommend you find yourself a good Scarab specific dealer that ships parts. When trying to purchase parts, you call them up with your HIN number (and year, model, etc. of the engine is nice to have too). And you order from them. You will have a really hard time finding parts on your own unless they are non BRP specific... then you have a chance.

Boat companies WANT you to buy from their dealer network. Nowhere else. It's fully locked in on purpose. We don't like this if you're a DIY, but dealers want to protect their servicing business for this reason.

The BRP parts catalog is a wonderful resource for BRP parts: BRP Parts Catalogs

Rotax > Rotax JPS (Jet propulsion system) > Two letter code corresponding to year where AA=2014 and onward > Engine HP > Twin engine etc.

Note that often engines are made a different year than the boat year. Mine for example is a 2015 boat year with a 2014 engine. You can look at the label on the engine which is located under TWO separate plastic covers. Remove the dip stick, pull off the plastic cover as if you're removing plugs. THEN AFTER there is yet ANOTHER slim plastic cover that can be peeled off. If you do, you'll find your engine label with more info.

 

[zipper]

Thank you @Luc

 

[cmckenn]

SOME parts are the same as Sea-Doo, but many parts are not. BRP makes parts for both Sea-Doo and Scarab. But they are not necessarily the same for many different reasons. Sadly, there is no part equivalency lookup between the two.

I highly recommend you find yourself a good Scarab specific dealer that ships parts. When trying to purchase parts, you call them up with your HIN number (and year, model, etc. of the engine is nice to have too). And you order from them. You will have a really hard time finding parts on your own unless they are non BRP specific... then you have a chance.

Boat companies WANT you to buy from their dealer network. Nowhere else. It's fully locked in on purpose. We don't like this if you're a DIY, but dealers want to protect their servicing business for this reason.

The BRP parts catalog is a wonderful resource for BRP parts: BRP Parts Catalogs

Rotax > Rotax JPS (Jet propulsion system) > Two letter code corresponding to year where AA=2014 and onward > Engine HP > Twin engine etc.

Note that often engines are made a different year than the boat year. Mine for example is a 2015 boat year with a 2014 engine. You can look at the label on the engine which is located under TWO separate plastic covers. Remove the dip stick, pull off the plastic cover as if you're removing plugs. THEN AFTER there is yet ANOTHER slim plastic cover that can be peeled off. If you do, you'll find your engine label with more info.

I wanted to wait until a day out on the boat before reporting back. Thank you so much for the advice. Not only on the mechanical issue, but the link to locate part numbers and diagrams proved to be just as helpful. I took your advice and started with the plugs. They didn’t seem too bad, but notice a lot of oil on the plugs and even the socket when changing. Replaced them, and still same symptoms. Ok, let’s swap ignition coils from one engine to the other……. Issue engine fired right up…. Symptoms moved to other engine. I’m a little embarrassed that I didn’t start with the simple fix first. From an automotive standpoint (I’ve never owned or worked on a jet boat) I skipped the plugs/coils because I’ve never seen that be the reason a vehicle didn’t start and only causes it to run rough. We ordered new coils and even backups but borrowed some coils from a friends sea doo jet ski for the weekend. The boat started every time with no issues and ran Perfect for 9 hours on the water with family today!!! The check engine light is still on and the codes are the same, but I’m guessing I need the software to reset. I can figure that out and the oil later, but huge thank you and grateful for your advice that allowed a full day on the water with kids, family, and friends! Hope this thread helps others!

 

[Luc Lafreniere]

Excellent news! Yeah, coils and especially plugs are a thing on boats. You should be replacing your plugs every 2 years. Personally, after winterizing using the old plugs, I wait until spring, start it up to burn off the oil on the plugs, then put new ones in for the season. I end up replacing them every year. I also keep a spare set in the boat with tools. You don't need to do this, but I would replace them every two years.

Coils don't usually need to be replaced, but it definitely does happen. Glad it was an easy fix in the end.

Some lights will go away on their own after running the engine for a certain number of cycles/hours. Nobody seems to know the magic numbers there. I'd run it for a while and if they don't go away, then you'll need to either bring it to a Scarab dealer or buy the at home software. If you plan on doing maintenance yourself (which sounds like it lol), then buying the at home software will be a must. It isn't cheap, but neither is going to a dealer. So as long as you plan on doing the work and have mechanical skills (which you obviously do, speaking for others here), then I'd look into it. Candoo Pro or BUDS at home are two available to you. Pros and cons to both. You can look that up.

Hopefully you get to enjoy the boat!