Bravo 3 MPI will not turn over

[27Sherwood]

I have a 2008 Sundancer 240. Was running great but suddenly will not turn over to start... Not even starter fluid could get it to go. Replaced all 8 spark plugs - same problem.

Please help!

 

[scoflaw]

Got spark. Got fuel ? So cranks but no start?

 

[27Sherwood]

Yes, she has a great spark, and IS getting fuel as told by the gas soaked plugs which are now replaced.
The motor is a Mercuiser 5.0 MPI

I'll add that it has run flawlessly for the past 4 & 1/2 seasons since the engine was replaced with a new one. I had it out a week ago for a few hours, returned to the club. No issues or indications of problems.

 

[Espos4]

Maybe it’s not getting fuel and you used too much starter fluid?? Is that possible?
Did you test fuel pressure at the rail?

 

[27Sherwood]

I had this massive reply ready to go and my browser crashed---!

Maybe it’s not getting fuel and you used too much starter fluid?? Is that possible?
Did you test fuel pressure at the rail?

I'm unable to test the fuel pressure, I do not have the tools for that. It is getting go-go juice for sure though. A burned fuse holder that I had found in the beginning of all this turned out to be for the fuel pump relay. The fuse was still good but the connections were so carboned up that current wasn't flowing. Why they use these tiny stab ins when they have a tone of real estate is beyond me. I sistered on a full sized fuse holder and heard the pump come on with the key. Cindy, the boat owner and the member here has been awesome in her non-stop quest finding online manuals etc etc that is making the troubleshooting process a lot easier! Much of the online videos etc are not specific to this 5.0 MPI so are only somewhat helpful. I have a lot of basic gas and Diesel engine knowledge with cars but this whole floating power plant is new to me ! At the end of the day though, very similar.

UPDATE: Last night Cindy and I spent some contorted, uncomfortable, quality time in the bilge working on it.... now we've set our sites on the crank shaft sensor. I have removed, which was not easy for me, the one retaining bolt but was unable to get the unit out. I've learned since that from the manual that "if the tachometer reads while cranking, the sensor is ok" ....I wish that I had seen that earlier, but will try that test today before fighting to remove a possibly good part!

ANY thoughts or suggestions on any of this (past posts included!) greatly appreciated! I will try and post pictures later. The fact that I did not drop either of my cells into the bilge puddle while taking pics with grease laden hands is amazing!

 

[27Sherwood]

Last night turned over engine with crank sensor connected and again disconnected to confirm. Crankshaft sensor passed the test....found out too that this part was about $270.00 locally. Pretty pricey but had it been the culprit, of course worth the money.

 

[scoflaw]

You have good blue spark on all 8 plugs and all 8 are gas soaked? Have you tried advancing the throttle to clear flood mode? Spark lost timing ? Not even a pop? Try a noid light? Sounds like it's just dumping fuel

 

[27Sherwood]

You have good blue spark on all 8 plugs and all 8 are gas soaked?

I cannot confirm the spark color aside from the coil's which was mostly blue

Have you tried advancing the throttle to clear flood mode?

Yes, on more than one occasion I've had the controls at WOT to let some air in/fumes out.

Spark lost timing ? Not even a pop? Try a noid light? Sounds like it's just dumping fuel

I located the timing marks on the pulley and TB cover. at that point it had been turned over a bit too much for the night and just needed to vent a bit. Also another guy had come over and suggested pulling the fuel line from the outlet of the tank-some of these fittings I'm told have a check valve which can stick. So I did that and confirmed mine doesn't have that valve. Confirmed too that there was plenty of gas in the line. Pretty fat line too when compared to a car!

Only "pop" is occasionally back through the throttle body. There has been small flames in there too sometimes. Never a pop like it's trying to run, yet!

A noid light= a timing light?

A club member & fellow Sea Ray owner who's still unfortunately on the hard, was nice enough to loan me a timing light last night. With the help of the patient boat owner Cindy, we tested again for spark (I admit this is a lot easier than the ground the end of the wire method) and "saw the light" on all 8 ropes + the coil wire.

Am I correct in assuming that if I put my timing light setting on "0" that it should pulse right in line with the notch on the cover/0 degree mark on the harmonic balancer?

We are working on getting a diagnostic tool. Hopefully it can tell us what's wrong.

 

[scoflaw]

Noid light tells you if the injectors are functioning with the ecm trigger. Nothing to do with ignition timing.

you need to get yourself a TSM

 

[27Sherwood]

I should have looked that up and not guessed apparently...I see them now. Thank you, I do appreciate the input!

 

[27Sherwood]

Where all standard means of troubleshooting have yielded 0 solid answers, Cindy ordered and received today a Rinda TechMate Pro scan tool.... heading up to the club soon to try it out.

 

[scoflaw]

If no codes and sensor values are within range, you got yourself a fuel issue.

 

[skibum]

Does the alarm go off when you turn the key on? It should. I have a lanyard switch on my throttle. If it is in the off position, I do not get the alarm when I turn the key, and the engine will crank forever but never start.

 

[27Sherwood]

Thanks gentlemen!

Does the alarm go off when you turn the key on? It should.................

Yes sir, and have rang out the switch with a meter. unfortunately and absolutely not the problem. I"ll add that I am now way too familiar with the sound of that alarm when powering up the ignition !

...................Did you test fuel pressure at the rail?

If no codes and sensor values are within range, you got yourself a fuel issue.

hmmm well, even though I said "I've tried all standard means of troubleshooting..." I will admit with the gas fouled plugs I assumed that I was getting fuel....I don't know if enough or at a high enough pressure though. I wish I had checked in here yesterday, I would have pursued picking up a fuel pressure gauge. I will be today.

The Rinda scanner is really good. It is pretty easy to use and does offer up a lot of information. Scan result= 0 current codes and the last code was about 10 running hours ago- steering fluid related. That was addressed immediately. I don't like how it lists the codes numerically and not chronologically. You need to dip into each fault and read the freeze frame to get the engine hours at the time the code was thrown.

Some confusion here, it lists in the distant history a camshaft sensor fault. In all of my searching and in talking to parts counter guys-there is no camshaft sensor. On a diagram of the engine "sensor locations" it shows a crankshaft sensor but not a camshaft sensor. I'd find it odd that the scanner would have that wrong but perhaps it is misnamed?

Anyways, as a test we unplugged the Crankshaft sensor and turned over the engine. it did not throw a code. I'm guessing that maybe it has to turn over more to throw a code? Another Crankshaft sensor test mentioned earlier it appears to be fine, I'm moving to the fuel pressure test later this a.m.

Thank you thank you for taking time to reply!

 

[scoflaw]

Did you check for spark on all 8 plugs?

 

[27Sherwood]

yes sir, see post #8

>........... loaned me a timing light last night. With the help of the patient boat owner Cindy, we tested again for spark (I admit this is a lot easier than the ground the end of the wire method) and "saw the light" on all 8 ropes + the coil wire.

...and I will check again today, with plugs removed and (hopefully pressure gauge in place)

Thank you! I do appreciate the help here!