Mercruiser 5.0 MPI problems

Providince

Recruit
Joined
Sep 23, 2016
Messages
1
Family bought our first ever boat in June of this year, a used 2007 Crownline 220EX. It came with a Mercruiser 5.0l MPI Serial OW673826 DOM Nov 2006. Needless to say our first boating experience was not a positive one. The dealer, who will remain nameless at this point, said the boat had been thoroughly inspected and was ready to go. We got the boat in the water and after 5 minutes, alarms went off and boat died and could not be restarted. During that 5 minutes there was no power and could never even get it in plane. Little did I know I would be getting my triathlon swim training by jumping in the lake and swim/towing my family back to the dock.

We brought the boat back to the dealer and they said it the impeller had disintegrated and stopped running causing an overheat. We paid to have it replaced and a month later we got it back and they said after much testing the boat was perfect and ready to go.

Got it back in the water and surprise it wouldn't start. They killed the two batteries. Replaced those and still wouldn't start and realized the starter was dead. Brought the boat back to the dealer and they said they'd have to replace the starter but they were too busy and it was too tough of a job.

Clearly the last straw with them. Took it to another shop and they got the starter replaced but found the motor to be running rough. They found no corrosion on the distributor but the spark plugs were bad and there was no compression in #2.

I have spent the last week reading here trying to find some glimmer of hope. We have spent a pretty penny for less than 5 minutes of boating time. Now trying to decide if we just take it to a better shop and have them get it running or since it is too late in the season what should we do ourselves to save some money? On the plus, time is on our side and we are fairly mechanically inclined.

I am sorry for the long winded post but wanted to vent a little. Guidance or suggestions are greatly appreciated.

Jeff
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
First up, do your own compression test. This engine is a standard Chevy small block, nothing complicated. Just treat it like you would a car engine. Next is to determine why there is no compression. Could be a gasket, a valve or rings. Use a leak down test to determine that. Once you know what the problem is, we can guide you with getting it corrected.

Chris......
 

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
40,718
Howdy

Sorry to hear about your troubles, boat for the future boating buys, always get a water test. If the seller will not take the boat out and let you give it a 15 minute run, just walk away. Folks usually don't buy a car without a test drive, boat is the same way.

Agree with achris, do a compression test. Pull all of the connectors off the coil (item 18)
http://www.mercruiserparts.com/bam/s...31852/12840/50

Move throttle handle to full wide open. Now remove one plug at a time, install the compression gauge and crank it over some. Write down the reading, put plug back in and go to the next plug.

So far as the distributer cap (item 2), it can look great and still be bad. You have what most call crap caps, because you never know when they will stop working, but still look good.

Edit: A boat salesman is no better then a car salesman
 

tpenfield

Moderator
Staff member
Joined
Jul 18, 2011
Messages
17,695
Do you have any recourse with the dealer that sold you the boat?

No compression in a cylinder is not exactly an easy fix and probably something that pre-existed when you bought the boat .

I think the dealer dumped a bum boat on you.
 
Top