2007 RZ2 MP 340 Starts and immediately dies

[bamaboy2006]

I am having a issue with my RZ2. Went to lake saturday and ran like a champ. Filled boat up with gas on Sunday and boat will not run at all. It will crank but immediately shuts down. Have put sea foam and a few other things in fuel trying to get it to run thinking it may be bad gas but no luck. Any suggestions?

Thanks

[freeheel4life]

This is the exact symptom of a deadman switch being open. Any chance your kill lanyard got bumped/removed??

[KoolAid]

Other thing is the low pressure pump could have failed. Start off with the kill switch then check fuel pressure.

[bamaboy2006]

This is the exact symptom of a deadman switch being open. Any chance your kill lanyard got bumped/removed??

Never even thought to look at this. If that is what it is I am going to be very unhappy with my self!

[bamaboy2006]

Other thing is the low pressure pump could have failed. Start off with the kill switch then check fuel pressure.

What should the pressure be? And I am guessing I check this at the schrader valve on the fuel rail?

[bamaboy2006]

This is the exact symptom of a deadman switch being open. Any chance your kill lanyard got bumped/removed??

I thought the boat couldn't start with the kill switch unhooked? It does crank but will not stay running like its not getting fuel. There is fuel pressure at the schrader valve. I pressed it down when pump was running and it shot gas every where.

[Eighty516]

Fuel pressure at that schrader valve should be between 35-45 psi. The exact spec. is 39 psi. You can rent a fuel pressure gauge from any auto parts store for super cheap to check it.

[freeheel4life]

Neutral safety will limit cranking but typically a deadman wont. I am not 100% on the MP set up, but I can say Merc and others will allow the engine to fire then it will dies almost immediately after it starts. Just why I thought it may be the deadman. Could totally be something else. Just found it odd that it ran great Saturday. Figured best to check the simple stuff.

I had a 12 RZ2 out once and it "died" just out from the dock and wouldn't restart. Panicked because wind was pushing me from the dock. After I collected myself I found that lanyard was hooked to the seat. I pivoted seat and popped the lanyard out. Just my "check the simple stuff first" thing now.

[KoolAid]

deadman switch kills power to ecm on that generation from what I recall. It will still allow it to crank.

[SATige]

2007 RZ2 MP 340 Starts and immediately dies

I experienced the same issue on my Mercruiser. It would fire then die. First time it happened, last season it was a burnt fuel pump fuse. Happened again this season and it turned out to be a bad electric fuel pump. On my engine, you can hear the fuel pump prime when you first turn the key to on. From what I learned in my recent experience, if you don’t hear the pump prime, it’s likely the fuse or the pump. Hopefully it’s just a fuse because changing the pump is a pain, only because of its location. Hope you get it sorted soon.

[bamaboy2006]

I experienced the same issue on my Mercruiser. It would fire then die. First time it happened, last season it was a burnt fuel pump fuse. Happened again this season and it turned out to be a bad electric fuel pump. On my engine, you can hear the fuel pump prime when you first turn the key to on. From what I learned in my recent experience, if you don’t hear the pump prime, it’s likely the fuse or the pump. Hopefully it’s just a fuse because changing the pump is a pain, only because of its location. Hope you get it sorted soon.

How did you diagnose that this pump was bad? I still can’t get it running. Changed filter (PITA) checked all the obvious stuff and still no go.

[bamaboy2006]

Ok. I checked every fuse I could find and every one was good. Still same issue. Turn key on fuel pump primes for about 10 sec and then turn key over and boat cranks right up and immediately dies back out. Is there a way to test to see if my injectors are working? Have good pressure at the fuel rail but just doesn't seem to be getting into the engine. Really wanting to get this going before next week and all the boat shops are booked for the next 3 weeks.

[dj2]

Did you check the fuses at the engine? Right above the starter there is a plastic cap with wires going into it, there are fuses in there. If it is not a fuse, it sounds like your high pressure pump is the issue. I had the same problem 2 years ago, of the fuse is good then it is likely the pump is failing, mine died without warning. Your low pressure pump along with the failing high pressure pump will be enough to start the engine for a second but not enough to keeping it running. I recommend a fuel pressure test as mentioned above.

[bamaboy2006]

Did you check the fuses at the engine? Right above the starter there is a plastic cap with wires going into it, there are fuses in there. If it is not a fuse, it sounds like your high pressure pump is the issue. I had the same problem 2 years ago, of the fuse is good then it is likely the pump is failing, mine died without warning. Your low pressure pump along with the failing high pressure pump will be enough to start the engine for a second but not enough to keeping it running. I recommend a fuel pressure test as mentioned above.

I did test those fuses and all where good. I am going to try to borrow a fuel pressure tester today. I know there is pressure there though because if you depress the valve on the fuel rail it shoots gas everywhere.

[bamaboy2006]

Where exactly is the low pressure pump located on this engine?