Mercruiser 5.0L MPI shuts off when in gear

bengaltiger14

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Hello all. I have a 2005 sea ray with the Mercruiser 5.0L MPI engine. Last night when getting off the lake, I put the boat in neutral while coasting up to the dock. I then put it in drive and the engine just shut off. It cranked back up everytime but shut off everytime I tried putting it in gear both forward and reverse. Any suggestions?
 

cr2k

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Re: Mercruiser 5.0L MPI shuts off when in gear

First guess is the short shift cable is bad.
 

alldodge

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Re: Mercruiser 5.0L MPI shuts off when in gear

Hello all. I have a 2005 sea ray with the Mercruiser 5.0L MPI engine. Last night when getting off the lake, I put the boat in neutral while coasting up to the dock. I then put it in drive and the engine just shut off. It cranked back up everytime but shut off everytime I tried putting it in gear both forward and reverse. Any suggestions?

Do you have an alpha or bravo drive? What is your engine serial number?
 

bengaltiger14

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Re: Mercruiser 5.0L MPI shuts off when in gear

Bravo 3 outdrive. I do not have the engine serial number right off hand. Also, It will rev up perfectly.
 

alldodge

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Re: Mercruiser 5.0L MPI shuts off when in gear

Bravo 3 outdrive. I do not have the engine serial number right off hand. Also, It will rev up perfectly.

Need to check for codes but sounds like it could be your Idle Air Control (IAC) valve. This is located on your throttle body and could be dirty. I'll try to get a break down and get back with location, but the serial number would help
 

bengaltiger14

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Re: Mercruiser 5.0L MPI shuts off when in gear

I know where that is but if that was the problem, would it not be shutting off at idle as well? It idles perfectly but only shuts off when put in gear (forward and reverse).
 

Bt Doctur

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Re: Mercruiser 5.0L MPI shuts off when in gear

shuts off like turning the key off? bad key switch? loose cannon plug? Also left a message
 

bengaltiger14

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Re: Mercruiser 5.0L MPI shuts off when in gear

Yes. Shuts off like turning the key off. Maybe even a little more abruptly.
 

alldodge

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Re: Mercruiser 5.0L MPI shuts off when in gear

I know where that is but if that was the problem, would it not be shutting off at idle as well? It idles perfectly but only shuts off when put in gear (forward and reverse).

Not necessarily, it can idle fine but when you put it in gear the IAC should since the decrease in rpm and adjust. Like I mentioned this is my suggestion from what I'm hearing of your symptoms. Need to check/clean the IAC, check for correct fuel pressure and make sure your flame arrestor is clean. After that I would check for codes
 

Fun Times

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Re: Mercruiser 5.0L MPI shuts off when in gear

Also follow the 2 shift cables to see if they are moving any electrical wires during shifting. Carefully wiggling wires around may help you find something loose causing the power to shut off.

The IAC and IAC muffler could still be an issue even though it's a newer unit. So you really shouldn't just rule it out. The muffler could be dirty as well. Did you replace the muffler last time?

Have you noticed any additional resistance during shifting?

Does it die only while in the water or on the trailer to?

If you don't find a loose wire shutting down the engine, then a marine scan tool may be needed to see what the live data is trying to tell you that may not be within normal specifications.
 

bengaltiger14

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Re: Mercruiser 5.0L MPI shuts off when in gear

Well. I figured out the problem this afternoon. Before I go into very much detail, keep in mind that it was pitch black dark when all this went down the other night.

So, apparently I forgot to take my dock line off the boat before taking off. When I got back to the dock, the line got wrapped around the propellers causing the engine to shut off. Therefore, the root cause of my problem was me not doing my due diligence in taking the ropes off prior to taking off.
 

Fun Times

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Re: Mercruiser 5.0L MPI shuts off when in gear

That would do it to.:) Night boating is a whole different adventurer. It's so common to concentrate on engine problems sometimes we tend to for get about things like ropes and things warped around the props, etc. etc.
 

achris

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Re: Mercruiser 5.0L MPI shuts off when in gear

I LOVE being out on the boat at night... It's SO different to daytime.... I know everybody's an expert after the event, but my suggestion would have been to check and make sure the drive wasn't locked up (But I was thinking internally)...

Glad you got it fixed.
 

bengaltiger14

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Re: Mercruiser 5.0L MPI shuts off when in gear

The outdrive appears to check out fine visually. Are there any other checks any of you would recommend before going back out?
 

Bt Doctur

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Re: Mercruiser 5.0L MPI shuts off when in gear

Make sure all the ropes and tydowns are away from the prop.
 

muc

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Re: Mercruiser 5.0L MPI shuts off when in gear

I have seen prop shafts bent by ropes. Might want to check the shafts for straightness.
 

Bt Doctur

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Re: Mercruiser 5.0L MPI shuts off when in gear

Somebody mention rope!!!!!!!!!!!!!!!!!!!
ropemussels.jpg
 
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