.4.3L MPI questions

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PeterB26

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My family has a boat with a 4.3L MPI engine with alpha outdrive. It has been running well all season though I personally haven't driven it for 20 years or more. On the day in question it ran great for an hour or so, then we stopped and spent a few hours on the beach. Then absolutley dead... either no spark or no fuel. Thought it might be a classic vapor lock, but no start the following day either.

Engine s/n 0M3367XX (I left out the last two digits because you won't need them to determine which motor I have and this is a public forum!)

I do not have the right scan tool and I don't yet posses the proper manual # 32, so it isn 't going to be me fixing it. But I am wondering if anyone has a link to a PDF manual that I can download quickly ( doesn't have to be free, but it does have to be the right manual and complete)

Also on that motor I have yet to see any obvious DLC connection point. Is it some earlier version? About where would it be found and what does it look like?

Also on the on-line partial scans of manuals I have found I cannot find a list of trouble codes. An ybody know where to get them?

As I said I am not going to be fixing this motor this time through, but I don't like being quite so "in the dark."
 
alldodge

alldodge

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Engine s/n 0M3367XX (I left out the last two digits because you won't need them to determine which motor I have and this is a public forum!)
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Your kidding right ??? Sure we can figure out what engine but can someone actually figure who you are from the serial numbers?

the proper manual # 32, so it isn 't going to be me fixing it. But I am wondering if anyone has a link to a PDF manual that I can download quickly ( doesn't have to be free, but it does have to be the right manual and complete)
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You want manual 32 in pdf quick. Just google mercruiser service manual 32 and there are several out there ready and willing to let you down load for a fee
 
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PeterB26

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I paid for a PDF download and went throught the annoying spam to get it at one site and all I got were the first 20 pages! Infected my computer with tons of spyware and made a general digital mess to no advantage whatsoever. Rather not do that again if I don't have to.

In my state ( and many others) we use engine S/N's as part of boat registration information... which is notoriously difficult to accomplish if you don't have every scrap of paper from the day the keel was laid.... so I don't need anyone pirating mine.

Tried the manual at " boatinfo" and it is all there and it is free, but a little difficult to use in that format, and aside from prnting a page or two at a time it can't be downloaded. still it is at least acess to a manual. I would love to have one of my own and I shall soon enough, though probably by hard-copy and U.S. mail.

Big thanks to Tail_Gunner for the link to the document with info on fuel injection and troubleshooting. I've been going over it and it is very useful.

Thanks to all,

Peter
 
Mischief Managed

Mischief Managed

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I hate the format and can't get the boatinfo manual to print either, but the price is excellent... Good luck.
 
Mischief Managed

Mischief Managed

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The DLC connector on your engine is only 4 wires and is right on top, near the thermostat housing, if memory serves. Turn the key on and look for +12 volts on the purple wire of the DLC, that will tell you if the purple wire is connected correctly.
 
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PeterB26

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I did see that 4 pin connector and figured it was probably the DLC... but I wasn't sure and could not find any direct reference to it in any manual. Most speak of a ten pin connector or variant, which I definately do not see anywhere.

One other thing I couldn't find any answer to was that the neutral switch ( not the shift cut out switch) has another wire on it. Two purple and one black. the black has a length of larger diameter insulator or casing for part of its length. Not sure what this is all about.

Peter
 
Mischief Managed

Mischief Managed

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I was under the impression the neutral safety switch was supposed to have yellow/red wires. Purple should turn on the ECM, but it goes all over the place through many splices.
 
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PeterB26

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Well.... yellow with red would make sense because you would think it would be in the starter (cranking) circuit. But nope. This one is purple, just like the shift cut out switch which is right beside it. Except the neutral switch has two purple wires and one black wire with some sort of extra something in the black wire. A fuse link? I have no idea and can't find reference to it. When disconnected and testing the switch with an ohm meter the two purple wires behave correctly indicating the switch itself is A-OK, but the black gives me about 8 meg ohm to either of the purple leads so very high resistance but not open circuit.
Boat goes to the shop mechanic today, so maybe he'll know something I have not been able to find out easily.

Thanks for your help, MM. And if I get any good answers I'l follow up by posting them here.

Peter
 
Fun Times

Fun Times

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PeterB26 said:
This one is purple, just like the shift cut out switch which is right beside it. Except the neutral switch has two purple wires and one black wire with some sort of extra something in the black wire.
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That's your gear indicator switch to tell the ECM if it's in gear or neutral......One of It's job's changes the REV limiter setting so you can't over rev the engine out of gear.

Item number 24, http://www.mercruiserparts.com/Show_Pictures3.asp?dnbr=834987 01&ivar=images/COMMON/1448.png&inbr=7801&bnbr=270&bdesc=Shift+Bracket%28Alpha+Engines%29

Engine still won't start correct? Do you know if you have any spark coming out of the coil? Use a timing light connected to the coil wire during cranking makes this testing job easier on you.

Since you prefer not to post the full engine serial number, what year is the boat?
 
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