Merc 8.2 B3 380hp problem
 

2016 merc 8.2 380hp
Was cruising around at about 2000 rpm and engine shut down like the key was turned off. All gages show like the engine is running and reading normal but all is dead - no click while turning the key - nothing - but I do have good battery power and again, all gages still read normal including the tach as if engine is running.
Any guesses at what could be wrong ?

Did you accidentally pull the kill switch? Make sure that is on and secure, could be something as simple as that.

Sorry I should have mentioned it, that was the first thing I checked....thanks for the reply though

best advice I can give a boat owner whom own a catalyst marine engine is find a well trained Merc cert shop and one that has a good repore with the OEM marine rep, Basically what I am saying is these engines are not a do it yourselfer fixer engine. One it takes a very vast knowledge base in the scanning of these engines and it is best to use Merc G3.

2 is the maintenance and even the boat owner knowledge how what not to do for an example - do not run a cat engine out of gas - why because it can blow a hole right thru the cat sub strake. that repair alone can be over 5 k alone depending. Also very few cat engines especially the 8.2 in the marketplace. If I was to guess since 2010 mandated cat engines from all Marine OEMS -- prob under 250K sold. and prob maybe 1500 were 8.2. if that.

With that said the internet for proper info based is just not there to learn anything from period.. Most boat owners do more harm to their cat engines because they think they know what they are doing or because something in the forums told them to do so. I am telling it like I see it in person.- 9 out 10 boat owners whom own a cat engine - jack things up trying to fix a isolated issue with their engine.

There is Service bulletins on these engines especially in the past, plus there is PCM recalibrations as well. That is all dictated by engine serial number. I would find a shop who see these daily. And that would be me as well. Marine gas catalyst engines. There might be a PCM recalibration for yours as well. A dealer is needed,

Gages and tach still show like the engine is running?
That seems really strange.

It is strange, the gages.... The boat is at the dealer now but I am not sure when it will be looked at. I was just curious what the experts here thought about what could be wrong.

posting your engine serial would be the best for answers. NOT sounding like a bad guy but experts for cat marine engines are not going to be found on the internet. Do not take this wrong. Example even on OSO is 99.99 % MPI (non cat) and carb info related.

Very rare cat topics come up and if they do most all poster have never even touch nor seen a cat marine in person. Just saying no offense to anyone. It is what it is and IMO should be pointed out for info received.

Post engine serial number to do some digging. That's the best start.

your engine is newer than this service bulletin but possible some of it might pertain about the issue(s) you are having. read away. These 8.2 can be a problem child. Man we had this exact issue from the related service bulletin back then. Engine just shuts off for no reason and or blows up going down the lake.

the full 30 pager of all that. I am fully interested in your issues and the outcome. Bulletin link below from the past. This is the 2 nd update version back in 2011. again not any or most of it will not pertain to your engine if in fact it is a true 2016 production date built engine but possible something in the bulletin could.

FIELD CAMPAIGN ON 8.2 STERNDRIVE ECT ENGINES | Service Bulletin | Crowley Marine

Thanks for the info but I'm guessing it is electrical because the starter won't even click when you turn the key. The dealer has the boat and will hopefully get to it Monday. I will post outcome when I get it.

If all the gauges doing that it maybe as easy as the main ground wire. It's only a guess...

no power on the engine side - still wonder how the tach reading rpms ? and you are showing even oil pressure - coolant temp - voltage and so on as mentioned in your post ---- all gauges reading. . . .

thought about this and without a wiring diagram in hand nor your engine --- my only thoughts on the logical side is the starter relay went bad or lost its connection and or the 20 amp fuse for the starter blew. Or both ?

The engine has a hot stud that uses 2 battery positive cables - one from battery to hot stud and hot stud to the starter. if any of that lost power the gauges would not be working. BUT WILL add. There is a 90 amp fuse at the starter as well..... Depending --- I can see if the 90 amp fuse at the starter blew causing a no start but still have power at the gauges . Possible 90 amp fuse at the starter ? I have to rethink that one. Its late.

I have a 2011 8.2 HO and experienced this exact problem. After putting on the G3 computer, and showed no issue. We found a loose term. to the starter. not very loose, maybe just enough though. I to was cruising along and engine just died like I shut the key off. Checked all the common things like kill switch, batteries, etc. I have analog gauges so it did not read like your's. Temp, oil press, volts, fuel all fine. Would not start right up. 24 hrs later ran like it always has?? Hoping that the loose wire was it!! Good Luck

that was my point completely lost engine power - and all at the dash still works ?

there needs to be questions answered as to the gauges - when power is turn off do all gauges go off as well or do they stay stuck ??

turn key on what exactly do all the gauges do ? for instance the tach is showing 0 or 2000 rpms ? whats voltage reading ?

What kind of gauges are these ?

Smartcraft gauges ?

IS THIS A DTS APP or mechanical throttle and shift ??

Also the 90 amp fuse might be on the hot stud / engine side rather than starter. They were moved it for a couple of reasons. One is to stay dryer. I can see if this was cabled wrong by dealer or boat manu - if the 90 amp fuse went out being the issue.

possible loose cable - pwr or ground connection knocked out 20 amp starter fuse.

that 20 amp starter fuse is more than just for the starter -- If you lost trim as well - this would be the issue for the no start - the engine dying while driving and starter not working. The 20 amp is for like 6 things. Now I have to remember what I want to say for supplies 12 V to the fuel pump relay ???? - The 20 amp fuse ??

The 8.2 have only digital output for gauges! Analog gauges did not work on this engines,only with an extra interface.
So i am shure he use scmartcarft gauges!
Michael

I was not talking about the signal for the gauges - I was asking what readings at the gauge and brand of gauges, plus there is other players making gauges for digital signals besides smart craft (Merc)

he can have vessel view as well as well

Matter of fact most marine gauges makers are doing gauges for digital signals., faria, V three, Livorsi, Medallian, BeBe, and so on

I needed a Merc. interface "go between" to make my analog gauges work with my engine. I used my boat for twice the time I had when I had the problem. No issue. I would feel more reassured if I knew exactly what the problem was.

Engine does not have digital throttle - does have analog reading gauges.
ALL gauges stay in the same position as when the engine was running even when turning the key off - run or start ..... all circuit breakers ok, two 40 amp breakers near dash ok. I did not see any breakers on engine
when shut down happened. Also, nothing works that requires the key to be in the "on/run" position to function.
The boat is at the dealer now.... we will see what they find, soon I hope.
Thanks for all the replies.

thanks for the update. Keep in mind the TACH works off the crank position sensor BAD crank sensor causes a no start issue but the starter to NOT turn over is another issue.

I would not rule out the crank sensor either here.

I understand your gauge set up - its set up thru the interface that is needed for digital signals to analog. With that said other areas need to be checked.

The interface, the PCM and the crank position sensor. IMO all need to be checked out very closely.

For ME this is the most interesting issue posted I have seen up here in a while. All Follow ups on your end would be appreciated . I am closely following this post and of course if it turns into a lunch eater for whomever, I would like to get a shot at fixing it even being many miles away.

Thank you for your input !! I will post what the dealer finds, hopefully soon.

The dealer called and said there was a wire in the starter/ignition circuit touching a head and causing a short. I will be talking to the tech tomorrow to get better info...

THANKS for the update and I would wonder if that 20 amp starter fuse was blown as I mentioned in Post # 15. That was my guest at first.

As I said that a 20 amp fuse is for the starter, for trim up and down and for 12 V to the fuel pump relay and couple more things.

What did you find out ? do you have full details on the issue(s) and the complete fix ? Thanks you can OSO pm me if need to be about any details or questions

The engine wiring harness arrived yesterday, I don't have PN, but still waiting for a seal PN 8M0044310 that they said may not be needed. They hope to have it ready for the weekend. That is all I know at this point.

I hear you more than just a loose connection and a chafed wire. Thanks for the fast reply.

If you want to but only if you want to ---- can you PM the dealer info who has your boat ? Kind of wonder if I know them.

Did some research and found the seals they are waiting for are for the intake manifold, I do not think this has anything to do with the other problem. I did note when I brought the boat in that is does not start like an E.F.I. engine should and after running engine at the dock for for ten or fifteen minutes, shut down, restart a short time later, it would crank and crank, not start, shut key and try to restart and then would fire up, may the seals are related to this ??

What was all done to your engine for updates and what completely fixed it ? thanks you can OSO pm if need to

This is what the repair order had on it. Boat is running fine !!

DIAG ELECTRICAL FAULT STARTER / IGNITION HARNESS/ TEST MAIN
CIRCUITS

RPL ENGINE HARNESS