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57 Merc died while running

divrddn

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"My 1995 5.7 Merc died after r

"My 1995 5.7 Merc died after running for about 10 min. today. Started fine and ran fine until stalled. It has elec. F.I., gas in the tank, its not the kill switch. F.I. is visibly supplying fuel so it seems to be a spark / ignition issue which I have no experience with. The starter was just replaced w/ new 2 wks ago and boat has been used daily until todays sudden conk out. All electronics are still working. Coincidence with new starter??? Any trouble shooting ideas? Thanks"
 
Take ignition module from the

Take ignition module from the distributor and check it out. If it is original replace it anyway.
 
"It could be as Simple as a Br

"It could be as Simple as a Broken or Misplaced Wire.....

You say all these things have been replaced,..
I Assume that you Hired to work out,.??

I'd be doing some Diagnostics before I started Throwing multihundred dollars Parts At It......

If You can't do it, Find somebody who Can.....
Maybe I'm Wrong, but the tone of your post suggests that You're Not doing the work Yourself...."
 
"The shotgun method will fix i

"The shotgun method will fix it eventually, but isn't very efficient, except for the parts store owner being able to buy that new house. There are only a few things that cause the ignition system to produce spark. Start at the beginning and work forward. Since it's injected, the ECM will need RPM input- that's the first place I would look. The second place I would look is at the coil- is there 12V where it should be present? Is the coil wire fully engaged? What about the other plugs and grounds?"
 
"The starter I did myself. Som

"The starter I did myself. Some stuff I do myself some stuff I have done in the yard. Only problem is getting to the yard in St. Thomas from St. John, USVI when the boat isn't running. There isn't such a thing as a SKILLED RELIABLE mechanic here on STJ so its up to me. Many who "claim" to be mechanics couldn't pass a field sobriety test at any time of day. Tomorrow I'll start the troubleshooting with small stuff first. Wires, connections, voltages etc. I'll relay more info. when I have it. Thanks!"
 
"Just some basics. How do we k

"Just some basics. How do we know it isn't a fuel issue? Is it throttle body injection where you can see fuel spraying? (suspect yes).

When it is in stall mode, would check for spark at the coil and at plugs using a tester or screw driver CAREFULLY laid within 1/4 inch of a clean ground while cranking over the engine.

Not sure, but the starter hot terminal is often the pick up point for 12 volt power into other systems. Make sure you check power into and out of the starter."
 
David I believe you're rig

David I believe you're right about the starter hot terminal and throttle body injection. I'll check back in late tomorrow or Tuesday after I check a few things out. Thanks and stay tuned!
 
"Jim C:
"It has elec. F.I


"Jim C:
"It has elec. F.I., gas in the tank... F.I. is visibly supplying fuel".

How much fuel did your eyes tell you the electric fuel pump put out? EFI needs a constant regulated fuel pressure or it can not inject what is not available. Hence stalling!

You have a 12 year old boat with an electric fuel pump. Is it the original fuel pump? I presume the fuel filter has had regular annual PM. I would suspect the fuel pump and regulator first and fuel filter and fuel quality (water)second.

The fuel pump can be tested by fuel output or by amperage draw; the higher the amp. draw the weaker the fuel pump. Check the service manual for pump output and the amp. draw specs. Good luck. Guy"
 
"as mr. (mista) Hays s

"as mr. (mista) Hays suggests, check spark, and fuel supply when in stall mode. if no spark is the problem, check voltage at coil. also reach back there and feel it. is it really hot? coil is oil filled, and in warm salty air can corrode thru. see it alot. You may find oil leaking from coil, but hidden behind engine don't notice."
 
"by the way, the number of &#3

"by the way, the number of "skilled, reliable mechanics" available is often related to the number of reliable boat owners who pay their bills, and don't blame their lack of maintenance on the guy who finds the problems they caused. this is not a cheap business to run. I have several years income invested in tools, training, and equipment. if a guy could make a decent living turning wrenches there, there would be plenty of decent wrench turners around. sorry, just venting. couldn't help myself. S."
 
"Scott:
Vent all you want.


"Scott:
Vent all you want. I agree with you totally. My independent mobile mechanic did all that I couldn't do myself and even advised me "how to" when I asked for help. Never tried to up-sell me on anything, showed me what needed repaired with a fair price, did perfect work and was paid immediately. I think he's in Florida for the winter; hope he returns here in the spring. Guys like him are as scarce as hen's teeth in SW Ohio.

Guy"
 
Lets see...maybe the "reli

Lets see...maybe the "reliable mechanic" shouldn't leave without getting paid. Burn me once shame on you...burn me twice I'm an idiot.
 
"Yea but what you are missing

"Yea but what you are missing is that you guys live in the US where there're tons of mechanics. Some are good, most are not. We live on an island where there are only a few mechanics. Makes it much harder to find someone who knows more than we do and actually will spend the time to do the job right.

Oh, and this thread is now in danger of getting hijacked.
"
 
Hijack away. You know my pain!

Hijack away. You know my pain! Everyone thinks "Oh you live in paradise" Yeah I do!! But there is a dear price to be paid otherwise even the spineless would live here.
 
Did some troubleshooting today

Did some troubleshooting today and we have current getting to the coil and no spark. Planning on starting with a new coil.
 
What about the coil wire to th

What about the coil wire to the distributor cap? Those go bad all the time.
 
All ign. wires were replaced i

All ign. wires were replaced in Aug incl. coil to dist. Contacts inside were corrosion free.
 
"I would still check that one.

"I would still check that one. I have seen new, out of the box coil wires that were bad.It's a lot cheaper and easier than swapping the coil, too."
 
I'll do that. I'm goi

I'll do that. I'm going to order a new coil anyway just to have a spare if nothing else. Here in the islands spare anything (crucial) is always good if affordable. The peace of mind that its already here is worth the $$$. Shipping can be as short as 3-4 days or it may take weeks depending on nothing in particular. Island time is alive and well!!! Coil looks like its 2 easy to get to bolts.
 
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