2003 mercruiser 350 mag mpi bravo 1 spitting and sputtering

diveman05

Petty Officer 3rd Class
Joined
Jun 27, 2012
Messages
91
Hey guys. Traded in the four winns for something bigger and it's giving me a headache. Watch the video it is spitting sputtering and not happy while running. Idles fine. Om620680 http://youtu.be/ZuAqEO6X9kA
 

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
40,804
Hey guys. Traded in the four winns for something bigger and it's giving me a headache. Watch the video it is spitting sputtering and not happy while running. Idles fine. Om620680 http://youtu.be/ZuAqEO6X9kA

Need to find out if it's thrown any codes. Put a fuel pressure gauge on the fuel rail and see what you have. How does it idle? What do the plugs look like?
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,544
Ayuh,.... Check the fuel filter for water, 'n crud,.....
 

Fun Times

Moderator
Staff member
Joined
May 16, 2009
Messages
8,825
Hi there, I would start with checking your fuel pressure before and while it's happening.

Also is the humidity moisture high in your area? if so, pull the distributor cap and look for moisture. Also read this on your distributor, http://crowley-cloudfront.s3.amazonaws.com/media/mercuryBulletins/001/04/2003/EN_06.PDF

You may want to do a new cap, rotor and spark plugs just so you know their good for a starting point.

http://www.crowleymarine.com/search_results.html?string=Om620680

Hope you find it soon, good luck.:)
 

diveman05

Petty Officer 3rd Class
Joined
Jun 27, 2012
Messages
91
thanks for the quick inital responses, just got in off the water and already had 3 good leads from you guys!! Will start working on it this weekend and keep everyone updated!
 

diveman05

Petty Officer 3rd Class
Joined
Jun 27, 2012
Messages
91
No Title

forgot i had a family outing yesterday, so just got home today, pulling the plugs, got the first 4 out, here they are.... Picked up a new fuel/water sep. and a fuel pressure tester so i'll be installing the new filter tonight and then the spark plugs tomorrow along with testing the fuel pressure out on the water. Also going to look at the distributor tonight. the PO said they just had it done so it makes me wonder if they did something wrong. Still have to make it up to the marina to have them check for any codes that it may have thrown.
 

diveman05

Petty Officer 3rd Class
Joined
Jun 27, 2012
Messages
91
No Title

forgot i had a family outing yesterday, so just got home today, pulling the plugs, got the first 4 out, here they are.... Picked up a new fuel/water sep. and a fuel pressure tester so i'll be installing the new filter tonight and then the spark plugs tomorrow along with testing the fuel pressure out on the water. Also going to look at the distributor tonight. the PO said they just had it done so it makes me wonder if they did something wrong. Still have to make it up to the marina to have them check for any codes that it may have thrown.

Gap says it should be .060, i can't find my gapper so i have to get a new one. any ways i've read a lot of people doing much smaller gaps, opinions on this?
 

Attachments

  • photo205035.jpg
    photo205035.jpg
    71 KB · Views: 0
  • photo205036.jpg
    photo205036.jpg
    73.1 KB · Views: 0
Last edited:

diveman05

Petty Officer 3rd Class
Joined
Jun 27, 2012
Messages
91
No Title

Got a few other things done, last 4 plugs out, changed the fuel filter, pic is attached of what came out... got the cap off, doesn't look too bad but might as well replace it while its off. The rotor is giving me an issue, one screw came right out, the other, 100% rusted, which may be a sign of the problem, but i have to get a few tools at lowes tomorrow to get that guy out. what do you think so far?
 

Attachments

  • photo205051.JPG
    photo205051.JPG
    155.9 KB · Views: 0
  • photo205052.JPG
    photo205052.JPG
    158.2 KB · Views: 0
  • photo205053.JPG
    photo205053.JPG
    159.6 KB · Views: 0
  • photo205054.JPG
    photo205054.JPG
    124.5 KB · Views: 0

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
40,804
So far I don't see anything that would indicate a problem. Most marine distributers due build up with some moisture. Good thing at the end of each season to have a look and do some drying out
 

diveman05

Petty Officer 3rd Class
Joined
Jun 27, 2012
Messages
91
So far I don't see anything that would indicate a problem. Most marine distributers due build up with some moisture. Good thing at the end of each season to have a look and do some drying out

Thanks alldodge, i thought the same thing really, should i say unfortunately, a glaring issue would be far to easy for a boat! Still going to replace the plugs and hopefully get that rotor out and replace that. The PO mentioned they just changed the distrib. but with that rust on the screw i'm doubting it, maybe he just did the cap, do you think its possible they twisted it a little and its off? Looking at that one service bulletin from fun times the 8 and the contact from the rotor do not line up as shown in the picture. They appear to be about 1/2" off
 

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
40,804
Thanks alldodge, i thought the same thing really, should i say unfortunately, a glaring issue would be far to easy for a boat! Still going to replace the plugs and hopefully get that rotor out and replace that. The PO mentioned they just changed the distrib. but with that rust on the screw i'm doubting it, maybe he just did the cap, do you think its possible they twisted it a little and its off? Looking at that one service bulletin from fun times the 8 and the contact from the rotor do not line up as shown in the picture. They appear to be about 1/2" off

The lining up of the 8 is a point of reference only for adjusting. According to what I have read the HVS distributer is press fitted and should not move. In the bulletin the rotor is lined up with the 8, then marked for reference and move 1-2 degrees clockwise. If it does not run better, the reference marks are used to return the distributer back to original position.

Also noted that if drops of moisture are found under cap the cap should be replaced. Another note with the cap, they are notorious for failing quite often, some have not even lasted one season and there is no visual check to determine if they failed.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
47,610
did you remove the one rotor mounting screw or was it never there?

I would also replace the cap.
 

diveman05

Petty Officer 3rd Class
Joined
Jun 27, 2012
Messages
91
did you remove the one rotor mounting screw or was it never there?

I would also replace the cap.

I did remove the one screw, it was clean and easy to take out just the other one is quite the opposite. going to lowes right now to hopefully get a grabit or something similar to get that other screw out. If that doesn't work i'm thinking i may have to take the whole distributor out and try to get it out there or get a new distributor...
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
47,610
or get a new cap and rotor, cut off the old rotor, use a vice grips on the remainder of the screw and install the new one.
 

diveman05

Petty Officer 3rd Class
Joined
Jun 27, 2012
Messages
91
replaced the plugs rotor, cap and fuel filter, took her out on the lake to test fuel pressure and she ran great so not sure which one it was, thinking the rotor but seems to have fixed it. thanks everyone for your help!
 
Top