Engine cranking not catching

H

huslayer

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Sep 8, 2015
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Hello, I need help troubleshooting a 2016 mercruiser 4.3 mpi engine, 32 Hours, I got it from the auction in TX, towed it to FL.

I changed the plugs, fuel filter, oil filter and Oil.
I found water in the oil filter but not in the dip stick!!

The engine started for like 5 minutes, I found it leaking, because one of the core plugs missing so I installed new one. I had to take the axhust manifold out to reach it.

Anyway now the boat is crancking but not catching, it start if i spray a starting fluid but dies after, i siphoned all the gas and poiured new gas in.

so it was staring but leaking, fixed the leak now it's not starting!!!

what else to look for?
 
alldodge

alldodge

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I found water in the oil filter but not in the dip stick!!

The engine started for like 5 minutes, I found it leaking, because one of the core plugs missing so I installed new one
Click to expand...
I'm going to guess right now that your going to need another motor. Water in the oil filter means there is a very high probability that water is also in the bearings.

TX had a real bad freeze so a lot of blocks got busted

Anyway now the boat is crancking but not catching, it start if i spray a starting fluid but dies after,
Click to expand...
Make sure the fuel filter is full of fresh gas
Bleed off some gas out of the fuel rail into a clear container and look and smell it. Should be clean and clear and smell like gas
 
C

cyclops222

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Good chance the engine is a bunch of used parts left over.
They drained all the water mixed into the oil. then put in new oil.
All Dodge is right about lots of southern area motors that froze and cracked motors.
 
ESGWheel

ESGWheel

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There are three basic ingredients for an engine to run: fuel (which means proper fuel/air mixture), spark and compression. While other things are needed like proper ignition and cam shaft timing, it really boils down to these three basic items.

But let’s first discuss your finding water in the oil filter but not on the dipstick. Water will sink to the bottom of the oil pan and thus be what gets sucked up first (the oil pickup is just off the bottom of the oil pan) and put that water in the oil filter. The dipstick does not go to the bottom of the oil pan and therefore would not be something that shows up on it unless the entire pan was full of water. In fact, I would guess that even if the very end of the dipstick was in water, it would not show itself as you pulled it out since the oil on top of the water in the pan would ‘wipe it away’ (oil is more viscous). When you hear folks talk about water contamination of the oil showing up the dipstick, they are referring to the frothy milky reside on the dipstick (or oil cap). This is a result of the engine running for some time with water contamination. I suspect your engine has not been run (other then your 5 mins) since its probable freeze which cracked the block (or head) in addition to popping the ‘freeze plug’ and put that water in the oil. This is not enough time to create the milkshake effect.

Thus, I recommend you do a pressure test of the cooling system as based on your post its highly probable you have a cracked block or head. This is not as easy as it sounds and my experience in this space is limited to cars where it is simple to do, so others or the internet may be able to help.

Bottom line: ensure you have engine block / head integrity first before trying to solve the no start condition.
 
Scott Danforth

Scott Danforth

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Missing core plug means the motor went through a hard freeze

EFI motors need a few sensors to read correctly prior to allowing fuel and ignition
 
Ptr.Torch

Ptr.Torch

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Boats run on water, but engines don't.

Water in the oil is concerning. About how much water? And, what did the oil look like? Options are, clean like honey, and new. Dark black, or milk chocolate brown. If the plug that was leaking was a freeze plug, do the test on your cooling system as mentioned above. A crack in your block or head will cause you to have a very bad day the next time you try to run it. (And the oil will turn frothy milk chocolate brown).

Water in the fuel tank might be your next issue. Am I correct in thinking you have EFI? Those require a high pressure fuel pump and the fuel rail is running 80 or 90 psi. If water got into the fuel while it sat, you had good clean gas in the pump, lines and rail when you started it. You used that. As it ran the pump could have started pumping the water. Now engines don't run on water, so when that reached the injectors, your engine stopped running.
 
bajaman123

bajaman123

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May 6, 2009
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53
That engine is likely in need of a lot of attention, if not a complete rebuild. People used to call the core plugs "freeze plugs" because they'd get pushed out if the block froze...which seems to be the case here...which MAYBE the block is okay but unlikely the cylinder heads aren't cracked...very common on the 4.3 when frozen. The good news is it is all 'fixable', you just need to figure out what all needs to be fixed. Water in the oil is NEVER good...period. One also hopes that you drained the fuel tank and put in new fuel before trying to start it...? Or had an auxiliary tank with fresh fuel in it? The fuel injectors on that MPI engine can be finicky. If you can beg, borrow or steal a RINDA code reader with the correct interface for your engine...do so and see what it says...that alone will go a long ways towards getting you on track.
 
C

Chris1956

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Mar 25, 2004
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Your motor is likely fuel injected, and it's systems are run by an ECU. You will need to get a service manual on it. Sometimes the ECU will turn off the fuel to the injectors, when it detects an issue. Alternatively, you may have some sort of electrical problem. You might doublecheck any electrical connectors, from where you removed the manifold. Disconnect and reconnect all of them in turn to make sure they are clean and well connected.
 
H

huslayer

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Sep 8, 2015
Messages
11
alldodge said:
I'm going to guess right now that your going to need another motor. Water in the oil filter means there is a very high probability that water is also in the bearings.

TX had a real bad freeze so a lot of blocks got busted


Make sure the fuel filter is full of fresh gas
Bleed off some gas out of the fuel rail into a clear container and look and smell it. Should be clean and clear and smell like gas
Click to expand...
Perfect! thank you!! I bled some gas out and it was looking like water! then fresh fuel started to come out... thanks for that suggestion, I didn't know there's a schrader valve... now it starts fine but there's a whistiling sound from the alternator and still need to address water in oil filter..i'll open different threads so I wouldn't confuse people...
 
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