383 mpi , buzzer , stalling help please
 

Hi Guys , So this weekend my buddy decided to drop is boat in the water for the first time this year. Avanti 22 with a 2006 383 Mpi Merc. I don't know much about those engines and their warning system but basically the boat run's ok for a minute or two and then run's a little rough and quits at the same time the buzzer goes .... Litteraly when you hear the buzzer with the motor idling the motor cut's out and drops rpm's and dies ...Even if fast idling , the second that buzzer goes off the motor drops rpm's ... it's somtimes hard to fire back up after quitting so I am thinking fuel pump , but this motor has 2 of them. How would I go about testing the pressure ?

Things we checked , Drive oil lever : good ( operating range and slightly above ) Raw Water pump : New impeller , T-stat : new , oil level : good and 40 psi @ idle ...

Any idea would be greatly appreciated

This is the motor

http://www.miamimarina.com/miamimari...CTS/383BOB.jpg

Thanks for the post Marc ! Oil levels are good, water pressure is good, engine oil pressure is good.

I changed the fuel filter when winterizing the boat and the boat was 50% full of gaz and we put stabilizer in it. I filled up the gaz to 100% this weekend. Dont know if the fuel filters (I have 2) could be clogged that fast ?

I have these 2 pumps on my engine:
-fuel pump:
http://www.boats.net/parts/search/Me...ler/parts.html

-fuel boost pump:
http://www.boats.net/parts/search/Me...%29/parts.html

Change the fuel filter/sep. again maybe...

^ Thanks , I think it's the first thing he will do but we will also try and grab a fuel pressur test kits form one of our friends and see how much pressure at the rails we are dealing with.

Honestly... Im kinda having the same issue...
Yesterday the wife and I took the boat on the lake for the first time this year... I had about 1/4 of gas from last year and topped it off with another 1/2 tank of 93. Changed the fuel separator and left the old plugs from last year in... figure I would change them after the first tank of gas.

SO... it idles just fine in neutral... in gear it will bog down and die, unless i give it some throttle to bring the rpms up. So basically it struggles to idle in gear. Everything was dialed at the end of last year...

At idle the fuel pressure gauge at the carb is 3.5/4.5 psi. Getting on plane the first time there was a few misfires but after that there was no issues getting on plane. Ran fine.

Im just gonna start with the basics...dump old and add new fuel... another water sep. and change the plugs. Go from there.

Woulld that motor store a fault code that can be scanned??

I think it does store codes , I will have to see who has a tool close by that won't charge the price of the scan tool just to scan it...

Your 383 should have ECM 555 in which is the same as the all the rest small blocks and V-6 models from 2001 and up until the CAT engines enter the market place.

Is the alarm solid or is beep beep pause beep beep

IMO I think you are saying solid - if so water pressure low - impeller was changed but if you have a bravo app then a very close inspection of the GEN VII waterpump impeller housing for scaring - any scaring hurts water flow and volume. Also your water pressure sensor could be bad. Again solid horn going off. It would be wise to have the engine scanned beforehand - look for fault codes and look into history and available power from the scan.

Rough running could also be the IAC - they are problem child for x amount reasons - some reason are because boat owners fault for lack of PROPER maintenance and other reason are because they are not reliable and fail.

Do you have Bravo one or a Bravo 3 or an alpha outdrive ?

Its only one solid beep like whenwe turn ignition key to on. The engine starts and run for a few second only then a solid beep then the engine stall

Its a 2006 Bravo 1 outdrive... I also have a oil outdrive level bowl mounted on the engine and level is right on the spot

I also would check IAC. I've had to replace a couple on my 6.2 MPI's over the years.

BUP - What maintenance are you speaking of that can affect IAC life? Is it replacing the small muffler/filter located in the throttle body? Thanks.

Yeah , I am also curious about the IAC .... here's what I am thinking ... if the engine drops significant rpm's because of IAC being stubborn maybe the buzzer is a result of a low oil pressure ? Like Chaoscube said it solid but short ...

I've been there before...save yourself a lot of time and effort and get it scanned. You'll be chasing things forever if you don't.

It sounds like there are multiple things. When was the last time plugs and wires were changed?

Water pressure sensor are a common problem for going bad. just an FYI

IAC longevity - when replacing to new - use a quality IAC sensor to begin with. I know a lot shop online and as always you get what you pay for. China stuff all over the place for marine parts,

Next is to clean mounting surface - install new gasket - install using properly torque specs for new IAC and do not crank down all in one pass.

things that shorten life of IAC

Dirty flame arrestor and or restricted flame arrestor -
dirty or ingested IAC muffler
dirty IAC muffler cavity
restricted passages and or hose connection to IAC
Improper belt tension and or off alignment of belt(s) creating belt dust
Belt dust and passing thru flame arrestor
rusted pulleys creating belt dust
Did I say belt dust huge killer of an IAC for these engines
Leaking hose connection
heat related
deposit build up pintle

And of course IAC failure can still take place even in a perfect world.

Boost pump, I have 3 psi
Check valve on the engine fuel rail ,I have 43 psi and when engine dies, I have 35-38 approx

I have removed the flame arestor for all the test I did

I have openen and tested the IAC...resistance and voltage is also good.

Going to drop the boat to the damn dealer tomorrow morning. I hope they will not take 2 weeks to scan the boat.. I will keep you posted guys and thanks for your help

Yep, that one got me recently...same with water temp sensor.

I don't think either of those would cause his symptoms but certainly could be the alarm problem.

Bravo app you should have gen 3 cool fuel - inside the that cool fuel and only that cool fuel set up is a 10 micron disc pad fuel filter - it is dead bottom inside the cell - they clog very easy and need to be changed once per year bare min, then you have the paper element fuel filter located in the basket pull out - the basket pull out is your water separator - it will collect water and needs to be dumped and check every so often. the fuel filter that's sits in the basket needs to be changed out bare min once per year as well.

I always change them at the beginning of the year but check all of it during winterization. Maintenance is the upmost importance of this cool fuel. 99 % of boaters never do it. hence fuel pump problems.

next is the internals of the gen 3 cool fuel has black paint - guess what peels off and runs thru then clogs the whole fuel system including the fuel pumps ? THE BLACK PAINT.

Your 383 in not the standard PRODUCTION Mercruiser engine. Yes it is a Mercruiser but comes from the reman side as drop in. I have seen them use Gen II as well as the GEN III cool fuel apps. Just giving you heads up about the GEN III because they do not have the spin on fuel water sep filter - everything is internal for the GEN III cool fuel including the fuel pumps - good luck

Also it is the upmost importance to drain the GEN III cool system itself during winterization. I have 3 here in TX that were not drained and all 3 leak water and one leaks gas and water - all at the cool fuel assembly. The rest of the boat and engines were properly winterized but they missed the cool fuel. FYI and again good luck

One last thing in addition to all the good advice here. Check your cap and rotor, they get corroded and just plain wore out. That could easily cause this.

I have GenII cool fuel system.
I changed the cap/rotor/spark plug wires 2 weeks ago before starting the engine. I check again this weekend to be sure everything is good and yes it is.
Waiting for news from the dealer for the Scan

The stealer called me back...

They passed 4 hours on the boat and they found nothing. They told me the ECM have no fault codes at all on their scan tool.
They by pass all switches, all solenoid, they by-pass from the motor to the dash and everything.
They said the engine stall after a few second because of a Ground Lost Somewhere.

They told me that the wire on the Starter was not well tighted and 1 cable on my Battery selector switch was also not well tighted. They said it may have ****ep up the ECM...do you think this is possible and this can be the ECM my problem ? They charge $2100 CAD +taxes here for this damn ECM...or they told me it could be the big main wiring harness that can have a problem but it will take hours to check all wires 1 by 1.


Please, let me know what you guys think... Thanks

Can you post the stickers that is on your ECM - I need to see what is printed on it. I do not want to say anything as of yet until I can READ IT. I might not even matter but I want to see and read it before anything else. Again you say you have a bravo app - is this a bravo 1 app correct and 4 sure you have the 383 not the 377 correct ?

Do not do anything to the boat until I see the all printed stickers on the ECM No BS - I am trying to help.

The boat is still all the dealer...I can take a picture of the ECM when I get the boat back.

They told me they will try to find a used boat close, with a 350mpi 555ECM and try it on my boat to see if it will start and if the engine will run more than a few seconds and not die.

The tag on the engine and the engine cover is 383, but the sticker on the motor says 377cid 6.2L MX...its a quicksilver repower 6.2L engine in 2006. serial number of the engine is 0M300000...here is the tag:

http://i46.photobucket.com/albums/f1...psvijmxq72.jpg

To me it sounds along the lines of a sticking IAC valve or loose TPS sensor that is out of adjustment, loose distributor something like that. I would check all your sensors out that control your spark and fuel, the littlest hair movement on a TPS sensor for example can cause something like this. Did you disconnect anything when you worked on it that you may have left off? I would do that before throwing parts at it. Maybe look into a program like scannerpro that gives you live feed of what your sensors are doing, but it has to be something along those lines.

This app is ECM 555 and scan pro I am 99 % sure is not set up for these but is for MEFI ECM's

I need your ECM stickers not the engine stickers. I already knew it was a repower from their reman sales division at Mercruiserbeing a NON production engine that was dropped in like I said in another post.

The ECM stickers are going to have its calibration codes numbered on the sticker itself that are mated per application.

In the meantime if the label matches what I ned to know.

Here is what I think YOU MENTIONED - fuel pressure testing - 3 psi at the boost pump - that's to low has this been fixed or doubled checked to verify its not the problem ?

After I check your ECM stickers and if that match is all correct, I will post what I think is your problem but I want to know about the fuel pressures and what are they when the engine dies also ?

here I just will post the info as to any possible fix for your app.

1. The shift in gear switch is bad or out of position -

2 next possibility - the HVS = high voltage switch - in which is the real name for the distributor on these apps. HVS is not phased / clocked correctly or properly. they will have to check the proper procedure on how to do it. That is very hard to write all out to fully understand it. If someone had this out and installed whenever this surely would be the problem. It has to be phased / clocked 100 % correctly along with the rotor. Seen it done wrong at least 100 times

3. The HVS (distributor) was turned however or its hold down bracket / bolt is loose in which allowed it to turn / move in either direction. They can use diacom to set it correctly by scanning the engine. Very common thing to happen Seen this at least another 100 times

4. Bad crank sensor and or any connections for it including wiring. been down that road especially throwing no codes and even no start conditions.

5.IF YOUR APP has a yellow flag breaker - they are junk and can cause running problems. . If your shop does not know what it is, you better find another shop.

6. IAC triple checked and possible another new one. been down that road

7. water pressure sensor - some can be bad right out of the box, been down that road.

8. the HVS cap itself - 5 & 7 bad crossfiring or the cap is bad. They use to be bad right out of the box. the auto side went thru this as well because for one year they all had bad batches made overseas. they are now fixed but anything older on the shelf I would not trust. Just saying. been down that road - the first one ate my lunch after installing a brand new out of the box - but never again

9. double check all grounds and battery voltage drops.

Good luck and I will look at your ECM stickers to see if anything that might be matched. I wrote you the story book.

The boost pump is a low pressure pump and the high pressure pump is with the cool fuel system the other side of the engine. The low pressure pump was 3psi and at the engine we had 43 psi. I can't find how much psi the low pressure pump should be. This 1st pump is just to pump the fuel from the tank to supply the other one.

I will try to go at the dealer Tomorrow and take a picture of the ECM

I'd love to know the percentage of times the ECM being blamed as bad for when they can't find out what's going on vs. actually being bad. I'm sure it's a small percentage.

As I said earlier Ive had similar symptoms before two separate times. One was the ground on the back of the engine being corroded. The scanner can't help with that because it looks like the key is turned off when the connection fades.

The second time was a bad distributor and the scanner can't help there. I've replaced both distributors on my 383s in the last few years with around 200 hours.

ECM's from going bad can be traced back to the end user as well. They hate vibration, they hate corrosion, moisture, they extremely hate voltage spikes. people who unplug their warning horns and keep running their boats with a faulty sensor especially a form of an IAC can knock out the ecm over time as well. Link below read post # 9 to form your opinion as to not what to do and possible why your ECM could in fact be the problem the child.


Also a proper AMP battery and cranking batteries only for engine running installed. No deep cycle batteries for cranking the engine and running,

http://www.offshoreonly.com/forums/d...ough-idle.html

I will add that I did nt say anything but - the people working on your boat as again the problems could have been end user self induced. Have no idea and not finger pointing but believe me many are in general.

This shop is surely working on a lunch eater. If in fact you have bad ECM you are getting a deal for 2100 dollars for a bill -

The freaking ECM is 1732 US dollars alone. I am sure they have at least 8 hours of trying to figure out what on earth is wrong with your boat. Now I am not saying this repair shop is a good one or a bad one, I can not make that call.

If in fact the ECM is the problem its lists for 1732 and to call them a STEALER over a public forum is not right - they are trying to fix your boat and these parts are not free. Give them a shot at it.

If it was me and you brought me this lunch eater then I seen were you called me a stealer over the net - I would call you up and tell you to come get your F in boat just the way its sits and never call me again. Just saying. if you can prove they are a stealer and rape boaters then that a different story. But then I would have to ask why did your bring the boat to them in the first place.

keep in mind all way up till last year I was a full blown dealer as well - I kind of get taken back a bit when boat owners really talk bad about dealers / real repair shops. NOT all of them are crooks. This marine stuff is human built, indepth problems can easily just pop up out of the blue. It costs a lot of money to stay on top of it yearly plus the special tools to buy.

And to add to this many lunch eater problems are self induce by the end user and especially a lot from the ones who think they can work on their own boats. I have been there many times in the 100s and a lot of the related problems can be traced back to the end user. I said what was on my mind. Sorry for the rant but my statements hold a chit load of water.

Sorry to call them stealer...I didnt want to offense someone here.

The thing is that I drop my boat there and only ask them to scan my boat for $45. They never called me after 1 week to let me know that there was no code on the engine and they decided to work on the boat without asking me if I accept this or not. Now I have talked with them yesterday and they said to me I owe them $400 now and the problem is still the same. They found nothing.

I understand and again not finger pointing at U or them. So did you get the pics of your ECM stickers ? and posted 9 things possible for the problem in order. You need to see if your boost fuel pump really is a 3 psi ? What did the shop say about that, if in fact 3 psi for testing ?

ECM scanning sometimes will show nothing and your boat runs very very badly - just saying.

I go to the dealer after my work and they were closed. I looked in their yard and my boat isnt there. I guess its Inside in the shop or they moved the boat to another shop to test an ECM or something else...I will call them tomorrow.

Am I stupid or it could be a good option....I'm thinking about buying a Carb/Intake/Dizzy old school mecanic....it will cost a lot less than the ECM if its the problem and always had performance boats with carb before and never had a problem.

I've swapped from EFI to carb.

If you like and choose this option, than it's fine, since it is you choosing it.

Will say the carb marine engines are less of a PITA over the long haul compared to MPI. Like with most marine engines lack of maintenance is the number 1 problem for a lot of failures no matter of the app. If you break that down - fuel and cooling will be on the top of the list for why the engine has more indepth problems of failures.

The negative side about changing a somewhat current boat model over to a carb app from MPI is the selling aspect of it. 8 out 10 buyers buying a family Rec boat and or a stock production boat want a fuel injection engine in the boat.

If the ECM tests good and you CAN get a straight answer on the fuel pressures - IMO the 9 things that I posted could be the possible fix, one of those or a combine of them.

With any type of repairing these darn marine apps it takes of course the know how, the process of pin pointing the problem, but really the process of elimination a lot of times is the true way to find the exact problem. Also sometimes luck comes into play as well.

You need to start from the beginning - when did this problem 1st start - has it got worse over time, What has changed with the boat / engine anything ? has it ever ran good ?

Call the people who are working on your boat and ask if anything is new plus get what is their game plan is ? I would ask them what has been done to determine the things that are NOT the problem - again like I said process of elimination. example : fuel pumps ? fuel pressure ? proper voltage and so on.

Do you want to say who is working on it ?

It's a 1986 22ft Avanti.

OH totally forgot about that was the boat app, the engine is 2006 so forgot the hull was that old. But with said I bet whomever the buyers were, bought into buying a MPI app for their boat - like what most buyers are looking for.

My bad also.

I have ride with the boat all summer long last year with any issues. When we winterize it, it was running like a brand new.


This spring I did:

Hardin Marine drive shower install
Spark plug wires changed
Distributor cap and rotor changed
Raw sea pump impeller changed
Thermostat changed
All filters changed
Outdrive and motor oil changed

I have started the engine on the lake for the first time at the boat ramp. It runs for 2 minutes...time to see the winter coolant going everywhere on the water, then clear water from the lake trought the exhaust. It runs about 2-3 minutes then the a BEEP and the engine stalled. I restart it and the engine starts to die sooner and sooner. Now I start the boat, it runs perfectly but only like 4 or 5 seconds
-tested the IAC & TPS
-fuel pressure was good at the check valve before the throttle body
-looked into the fuel filter to see if there was something
-tried with new 91 octane fuel in a gallon



-no codes showing on the merc scan tool
-the dealer by pass all the switches and relays (ignition, shift switch, things upfront under the dash and more)
-they looked at the connections at the ECM they told me
-they found that the wire on the starter was not well tighted and a cable going into the battery selector was also not well tighted.

-Now they think the ECM is defect or a ground is bad somewhere but they checked everything except the big main harness (cause it will takes hours and hours to check this out they said)


Here is the story in details. I will call them Tomorrow to see whats going on. If there is no news from them, I will bring the boat back to my shop and do more test myself. I will put back OLD distributor cap & rotor and spark plug wires also and see if its the problem. If not, gonna also double check IAC and TPS and connections from them to the ECM. As for the water pressure sensor...it will cause a Fault Code in the ECM, no ? And I didnt touch to this.

Good plan.

If it still starts fine and dies, unplug the AIC right after it starts and see if it keeps running. Unless BUP thinks this is hurtful to the ECM. I do this with GM TBI's on GM vehicles for certain diagnostics.