Need some help! One of the engines won't turn over.....2015 scarab

[nick731]

Hey Guys, thanks for your help! I have a 2015 215 HO impulse and we got a late start out this season due to a surprise baby.

We go the boat into the water and the first engine cranked up easily but I cant get the second unit (port side) to turn over. It is trying to start but no go. I swapped plugs to see if that is it but that didnt help. The battery seems strong (and fires the first) so I'm thinking that's not the issue.

I thought perhaps bad fuel from the off season but the first engine fires and runs no problem...

Do these have traditional fuel pumps? maybe the engine is not getting the fuel it needs?

any other ideas?

Thanks guys!

Nick

 

[Luc Lafreniere]

So it DOES turn over, but doesn't actually start. Right? Just to be clear here because those are two different issues.

Assuming it's cranking, then spark, fuel, air is what runs the engine. Since your fuel is working for the other engine, I don't see why it wouldn't work for the other. The most likely is spark. I'd start by making sure all coils are working and sparking correctly. Agreed your battery is probably fine if it's starting the other one.

The other option is air flow... but the spark is more likely in my opinion. I'd go there.

 

[nick731]

Thanks Luc! Yes it does turn over, just doesn't actually start. I changed the plugs but didn't mess with the coils or the plugs that hold the spark plugs. I can check that. based on the fact that if turns over I'm assuming that starter solenoid is most likely fine too? along with the spark components I may also look at the relays..

Thanks for the help, I will report back. If anyone else has other ideas please share =)

 

[Luc Lafreniere]

Yes all around. Relays are unlikely in my opinion, when they fail, nothing cranks usually. But worth checking for sure. Since you have another engine that works, you can swap parts around to figure it out at least. That should be very helpful.

I'd also check around that engine for any loose hoses and wires.

 

[nick731]

ok thanks again for your help and all that you contribute on the forum @Luc Lafreniere !

Here is what the problem was:

A simple relay!

Big thanks to @ScarabMike for his posting here: https://jetboaters.net/threads/rotax-owners-keep-this-handy.13017/

There are tow main relays per engine, one labeled starter (or something similar) and another labeled electrical (or something similar). If the starter relay is good, the engine will crank but if the electrical relay is bad then it will not fire/start.

This was our case, the electrical relay had gone bad on the port side. You can tell by removing the relay located in a small fuse panel box near the engine and shaking the relay. If you hear anything then assume it is bad, you should not hear any shaking sound etc. In our case it was actually hard to hear, but sound a rattling sound was present.

Another thing to note that was referenced to by @philupngo in Scarabmikes original thread is that our dual engine setups start their sequence on the starboard side and then move to port. i.e. if your relay was bad on the starboard engine you would not be able to get either engine to crank. Since ours was bad on the port side our starboard engine would crank but the port side wouldn't. Just something to keep in mind.

Last thing to note is that after replacing the relay and finding success immediately cranking both engines I had the engine light and gear wrench light activate (they were not there before). I then decided to see if going for a rider would help clear these. Almost immediately the gear wrench icon went away once I started driving the boat at speed but the engine light did not. After the ride however I cut all power and then restarted the boat and the engine light also then disappeared.

So now we are all good to go over a $5 relay =)

I would take ScarabMikes advice in the thread link I posted above and grab a couple extra relays to have on hand just in case!

 

[Luc Lafreniere]

Excellent. Glad you figured it out and documented here for others. I don't have the twin engine setup, so good that you wrote those details.

Yes, keep a few relays in your spares. They should really have a few in the fuse box when you buy the boat. Otherwise dealers should just throw them in.

Happy boatin'!

 

[ScarabMike]

Glad to be of assistance!!!