Help with 5.0 ,pi engine please

S

Skydiving195SPer

Member
Jan 19, 2016
144
Under the Sand in Five Dock
Boat Info
Sea Ray 15 Sport
V8 5.0L 260hp MPI Mercruiser
19p Prop

Sea Ray
350 SunDeck on it's way!!
Engines
V8 5L MPI Mercruiser
I have a 5.0l mpi mercruiser and the oil sensor switch rusted off and dropepd alot of oil. My mechanic says it dropped onyl a bit and kept the rest but it took alot to fill back up.

The way this happened is the alarm wen toff and the engine shut down. I was near rocks so had to mvoe fast and i got it started about 4 times to move it. Each time the alarm would go off and the engine shut down.

I am told that the engine shut down each time because it was protecting itself and telling me i aint going anywhere until the problem was solved. Could i have done much fdamage to it? Seeing it shut down each time is this a protective mechanism from the computer?

Now on the computer it says nothing is wrong with the engine except it was reading that it is in neutral. This problem was solved and i am told it also says a accessory fuse keeps blowing but i cant figure out what it is for, or my mechanic cant i should say.

What is happening is that the motor will not start. We have fuel and apparently we had spark but when i got a second mechanic to look at it he said there was no spark and i had to replace the ignition coil,. which i did and then he said there was fuel and spark but he said the compression was stuffed but he did not check it, He said that it went bang like a shotgun when putting fuel straight in the engine to see if it would start. I donty know anything about thsi stuff but maybe somene here can picture what he meant. So he stopped working on it and then he told me over the phone that the distributor cap had been craked by my original mechanic, whcih of course the original says the second guy did it. It turns out that not only did i not need the ignition coil which cost a fortune but now back to my original mechanic who now has the baot, he says the second guy not only cracked the distributor cap but he craked the base of it as well. So i got this new part for $1000.

Can someone tell me why my engine will not start and has not started since we replaced the oil sensor switch? My original mechanic who sold the boat to me thinks everything is fine and it is some sort of safety that originally made the alarm sound and stop the engine. He thinks something is not reset and letting the engine start.

the engine wants to start but it just wont turn over. kind of like it has a immobiliser like with cars.

My mechanic has said he will do whatever it takes to get it working even if that is take parts from one motor to put on my one or even if he has to fully rebuild it, he will do this at no cost to me but it really seems like it is something simple staring us in the eye and is like an immobiliser is not letting it start.

Does anyone have any ideas as if it is an electrical problem then i figure someone here might know about the ECu and why it is not letting it start.

The engine is a 2006 and it has 250 hours and the computer shows that 340 of those hours are all run between 1000-3000 rpm so it has not been doing hard labour and it is in really good condition, apart from that oil sensor switch which looks like it sits in the bilge area and rusts. The rest of the engine looks immaculate.

Thanks guys
 
Sounds like a dumb idea but disconnect your battery for a day. This will let your computer die and possibly erase anything it remembers. Other that. Do you know how he fed fuel to your motors directly? Did he tear the plug wire connecting your Cap to the dist? One of your mechanics seems to be a bit of a hack job. I would stick my head in there and make site nothing else is broken and I would be teeing to figure out who broke your 1000 dollar parts. Did they set your timing back correctly when they reinstalled your dist? If he broke something on the base that means he moved it enough to knock the timing off. That also could have caused the shotgun sound. (Missfire). Why didn't want of them run a diagnostics test and clear the computer. Also just for a little fun make sure your kill switch lanyard on your shifter is in the right position
 
Xplicitlnck said:
Sounds like a dumb idea but disconnect your battery for a day. This will let your computer die and possibly erase anything it remembers. Other that. Do you know how he fed fuel to your motors directly? Did he tear the plug wire connecting your Cap to the dist? One of your mechanics seems to be a bit of a hack job. I would stick my head in there and make site nothing else is broken and I would be teeing to figure out who broke your 1000 dollar parts. Did they set your timing back correctly when they reinstalled your dist? If he broke something on the base that means he moved it enough to knock the timing off. That also could have caused the shotgun sound. (Missfire). Why didn't want of them run a diagnostics test and clear the computer. Also just for a little fun make sure your kill switch lanyard on your shifter is in the right position
Click to expand...


The original mechanic who now has my boat back, he has paid for the $1000 part and will do what it takes to fix it, even if he has to rebuild the engine. He just is slow at doing things.

The kill switch is in the right position, tried this already.

Thedistributor cap has not been refitted yet, only purchased and delivered.

Are you sure disconnecting the battery will erase the computer memory?

He did run a diagnostic test and clear any errors and the only error was saying it was in neutral. When i say hook up to the computer I mean diagnostic test.
 
with the mpi, you should be hearing the fuel pump cycle and pressurize Y,N
Is there a plug for the dist Y,N
Do you have an engine serial number?
 
Go with Bt doctor he knows lots more then I do. I was just throwing ideas out he will actually diagnose your issue
 
Skydiving195SPer said:
Yes.
Not sure what a plug is? It was a distributor cap with a long shaft.
ow619356
Click to expand...

Ok, So it turns out there is no spark. Compression is 150psi in all cylinders.
We have tried everything for spark and figure it is something elsectrical.

it is as if the alarm that shut the engine down is still not letting it get spark. We can not figure out why but it has to be something easy. The ignition itself has also been replaced.

Tursn out the second mechanic who made me get those parts lied telling me that this new ignition coil got us spark and that the compression was stuffed as all his words were BS. This guy should be shamed but right now im more concerned about getting my boat going.

I looked at the diagnositcs today and most of the hours under 2999. Only 6 hours up around the 4900 rpm.

The engine is in excellent condition. if anyone has any ideas about why we are not gettnig spark after changing the oil pressure switch and assembly plus new distributor cap plus new ignition coil, would be really great.

Thanks 20160203_183706.jpg
 
FYI We took the ECU out and replaced it with another ECU from another boat and it still would not let us get spark.
There is a goddamn sensor somewhere stopping this from happening.

To whoever gets it right for me on their first attempt (only because it is so hard to wait for replies and ask mechanic to give me the attention), to whoever tells me the solution on first attempt will get a $500 doantion to their paypal account or bank account. To me it is well worth the money to get this going as I badly want it going before summer is over.

I plan on being in these forums for a long time now I am sea ray thru and thru, so I will back up my promise with action like an honest person would
 
So if it ran briefly with the damaged oil pressure switch, but doesn't with a new one, I would revisit that area. Bad new switch, bad connection there or anywhere those men touched. Back of dizzy. Red reset button up top.

Is that fuse you mention still blowing ? Make sure there's a rotor under that dizzy cap, There was also a run of bad caps for that engine
 
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sky, left a message it looks like there is a oil sender and a fuel pressure switch just above the oil filter. neither has anything to do with loss of spark. you might have to start testing with a trouble light to see if there actually is power to the coil. see if there is a pink/white wire at the coil . you need 12v at that wire to power the coil and fire the injectors
 
The oil pressure switch is down the bottom on the opposite side of the oil filter if i am correct?

I did find a wire with a ring on the end of it and it looked cut on the other end, under the engine today. I am now wondeirng if that is a grounding wire for the oil pressure switch or some other wire for it.


Lets forget about what everyone did for a second and ill take you though the mian things so it makes sense....

Engine alarm went long continuous beep and then engine shut off.
Oil pressure went to zero and oil was in the bilge. Dipstick was dry. I am told that there could be some oil still in motor but it was shutting off to tell me i wasnt going anywhere unless i fix it.

Tried about four times to move it a little bit at a time to get away from rocks. Was barely anything.

Changed oil pressure switch

Boat would not start.

Found we had no spark and thinking that the engine safety mechanism is not allowing spark because it does not know we have changed the engine and filled it up with oil.

I now think that wire under the engine could of been fromt he oil pressure switch and will find out in the morning.

Distributor cap has been changed, so has the ignition coil and the iginition at dash.

We even changed the ECU and it still would not start or give spark.


So before this oil pressure switch rusted off fromt he assembly everything was fine. Now that happened there is no spark. Surely it is something simple that has not reset on a safety mechanism on the engine.

There are no faults on the computer.

Here is a photo of the live data from the diagnostic computer. (dam it, i will do that later as i exceed my data quota on this website)
 
the pressure switch has a plug end, not a wired one. did you get my message
 
From cranking over a bunch of times trying to get away from the rocks could he have burnt out a fuse? (Ignition, main harness, big red breaker switch just to name a few) also I know mines a little older but I had a similar issue were the grey wire going from distributor to the tach was causing it. (Bad tach or was that my sync gauge) I don't remeber.
 
Xplicitlnck said:
From cranking over a bunch of times trying to get away from the rocks could he have burnt out a fuse? (Ignition, main harness, big red breaker switch just to name a few) also I know mines a little older but I had a similar issue were the grey wire going from distributor to the tach was causing it. (Bad tach or was that my sync gauge) I don't remeber.
Click to expand...


I think i read somewhere that someone removed the wire going to their tach and that allowed it to spark. Is that correct? So this is a grey wire then?

Also im reading all about a blue wire going from the oil pressure switch or a grounding one. What should this be connected to?

Now behind my dash I see a purple wire with a plug end. The type with a plastic tube over the connector end and nothig is plugged into it. is it possible this is something that does nto need to be connected?

Ok, so can anyone tell me if i was to take this to a mercury mechanic, should they know pretty much straight away what is wrong or would they know a system of checks to be made as process of elimination to eventually find the problem and most importantly how many hours would one guess it would take to go through that process of elomination?Im asking because im wondering if its going to be a mammoth task.


'Also, could they glance around the engine and be able to see the problem, oe will they be needing to maybe pull all the witing which wouldbe a massive job?
 
Can you please tell me where i find these fuses you speak of?
I know the fuses under the dash but i am having trouble finding other fuses around the engine. My mechanic is a good bloke and doing hsi best but id like to be able to helpo him out so he can get on with other boats. Pictures or description would be a great help.
 
sorry but can anyone point me to a manual that specifically has all the electrical wiring and fuse diagrams for my engine?

I have this link but not sure if its mine or not....
http://www.atlanticmobilemarine.com/service manual 5&57.pdf

There is also this which id love to know if correct...
http://www.*******.com/merc/techbk/96/96hgd4.pdf

I then have the boat manual but again not sure if it has everything i need.....

(can not find this manual....can anyone else locate it? I keep locating the 185 sport. I use to find the 195sport

Btw, here is a parts manual if anyone wants it..
http://www.searay.com/boat_graphics/electronic_brochure/Company1729/1C1_24_74DEIPR93JZ.pdf
 
First thing you need to do is SLOW DOWN
pretty sure you need #31 are you usa?
 
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Sorry not familiar with your specific boat so can't tell you were the fuses are. Yes is the grey wire but that's specific to my boat vintage. It may be to yours but I'm not sure
Not sure of the blue wire and not sure of the connector that is behind your dash. Spend some time with boat doctor I hear he's very good and like he said slow down take a breath and think about what u did and or didn't do
 
Yeah I hear you on slowing down but it has been three weeks so this along with dying relatives and other big issues going on, it is kind of got me at my wits end.
 
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