Mercruiser 5.7 EFI 2001 not starting after run

rochy

Recruit
Joined
Jun 6, 2010
Messages
1
Hello,

I have a chaparral 2001 with a mercruiser 5.7 EFI. I can run the boat for most of the afternoon pulling daughter tubing, shutting off occasionally, and then at some point the boat will not start. Seems to be getting fuel but won't start. I can let it sit for about an hour to 1 1/2 hours and then it will start and run fine back to the dock. Usually load it and take it home.

It is not getting hot and runs fine until this time. Thanks in advance for any thoughts
 

fossill

Chief Petty Officer
Joined
Jun 20, 2009
Messages
427
Re: Mercruiser 5.7 EFI 2001 not starting after run

Grab a copy of the merc service manual for that engine (you can download off here in the adults section) and get a scan tool. The manual pretty well walks you through the diagnostic procedure. Take both along next time you take the boat out as intermittents are usually hard to trace unless the malfunction is present at the time.
Off the top of my head I'd say to check the fuel quality and filter (no ethanol or water contamination and I believe it needs 30 psi pressure) and unplug the MAP sensor next time it don't start. If defective they can also cause a no start condition. Easy to check, but do get a manual and scan tool. And dont use anything but a high impedance multimeter or you risk frying the ecu.
 

FunInDuhSun

Chief Petty Officer
Joined
Apr 25, 2010
Messages
414
Re: Mercruiser 5.7 EFI 2001 not starting after run

I had the same year and engine installed in my old boat. While still under warranty it had the very problem that you're experiencing. Took the dealer almost all summer to figure it out, but the fix was pretty simple- the ignition coil was getting hot and causing the engine to act up. Once it cooled down it was A-OK - for awhile.
In my case, the coil had some black goo coming out. Once the dealer installed the new coil, the problem disappeared.
 

fossill

Chief Petty Officer
Joined
Jun 20, 2009
Messages
427
Re: Mercruiser 5.7 EFI 2001 not starting after run

Yup, coil would do, or anything else electronic. Electronic defects usually show up under hot conditions.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,468
Re: Mercruiser 5.7 EFI 2001 not starting after run

and then at some point the boat will not start. Seems to be getting fuel but won't start. I can let it sit for about an hour to 1 1/2 hours

Ayuh,.... During that hour to hour,+ 1/2,...
Is the time to Diagnose the issue,...
Actually Check whether it's lacking Fuel, or Fire....
 

fossill

Chief Petty Officer
Joined
Jun 20, 2009
Messages
427
Re: Mercruiser 5.7 EFI 2001 not starting after run

You can also put that scan tool on right away and check to see if it has a diagnostic/malfunction code stored. You might get lucky.
 

bbordin

Cadet
Joined
Aug 13, 2009
Messages
8
Re: Mercruiser 5.7 EFI 2001 not starting after run

Anybody have a recommendation on an inexpensive scan tool for boats?
 

ddclapp

Cadet
Joined
Jun 8, 2010
Messages
28
Re: Mercruiser 5.7 EFI 2001 not starting after run

I had a similar experience with my 260R - I would run fine for a while and then things would start bogging down and die at idle. This usually happened when I was running WOT for several minutes. I then could crank an crank and no start. Two things gave me a hint - I seem to be running a bit hot a WOT (5-8 degrees over normal) and after things cooled down I could restart (1 1/2 to 2 hours later). So definitely a heat related problem.

I then replaced my ignition coil and spark plug wires and solved the issue. I am not sure which it was (coil or wire), but I have been running two weeks with no issues.

Just thought I would relay my lessons...
 

brpesa

Seaman Apprentice
Joined
Aug 30, 2009
Messages
37
Re: Mercruiser 5.7 EFI 2001 not starting after run

I had the same problem with mine 5.7 EFI
And it was ECM computer module.
I bought used on eBay for $350 and starts any time.
 
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