|
Originally Posted by mrfixxall
(Post 3387492)
i guess it could be timing but you said that you already had the heads off and that should have been checked when it was put back together..
35 psi is ok but it calls for 37 psi..have you checked the mechanical pump as well? 3-7 psi @ 2000 rpm's..even tho you have 35 psi of fuel pressure you may not be getting enough fuel to the cool fuel pump..did you check pressure idleing or out on the water.. a bad injector will act like a fuel pressure problem also.. |
Originally Posted by Boat1
(Post 3387362)
It may have lost an exhaust lobe on the camshaft. Those symptoms lead me there. Hope I'm not right.
Dont worry, your not right!!! you said the ignition timing was set correctly, have you checked the cam timing? what do the plugs look like? Honestly, sounds like a huge vacuum leak to me. need a scanner so you can see what the map is actually saying and see fuel trims as well |
Originally Posted by NOPUN
(Post 3387565)
Dont worry, your not right!!!
you said the ignition timing was set correctly, have you checked the cam timing? what do the plugs look like? Honestly, sounds like a huge vacuum leak to me. need a scanner so you can see what the map is actually saying and see fuel trims as well |
Fixx
Originally Posted by ridefast77
(Post 3387505)
nope timming checked out so its not that, there is no mechanical pump on a gen6 just the cool fuel, And when i replaced ther fuel pump last year i put to new injectorin to ...yeah i know alot of money in parts not to fix the prob. thats why im so irritated over the hole thing.
|
Originally Posted by mrfixxall
(Post 3387676)
so your saying theirs no fuel pump on your sea pump???? looking at a 97 formula as we speak and theirs one on each mpi engine's sea pump.. the electric pump in the cool fuel cant suck the fuel from the tank to the resivour..their should either be a mechanical fuel pump or a inline electric pump to feed the cool fuel pump..
|
My 98 7.4 MPI (L29) only had cool fuel pump as well. That is normal.
|
Originally Posted by NOPUN
(Post 3387565)
Dont worry, your not right!!!
you said the ignition timing was set correctly, have you checked the cam timing? what do the plugs look like? Honestly, sounds like a huge vacuum leak to me. need a scanner so you can see what the map is actually saying and see fuel trims as well |
Fixx
Originally Posted by ridefast77
(Post 3387683)
nope no pump on the sea pump just the cool fuel ...on 97-00 gen6 there is no pump on the sea pump...are you looking at a 454mpi OR a 454 mag mpi there is a big diff. the mag mite have the fuel pump on the sea pump.
just like it shows in the pic under fuel pump.. http://www.mercruiserparts.com/selec..._nbr=809994965 |
Originally Posted by Boat1
(Post 3387789)
Good to know. Have you ever heard an engine with flat cam lobes? Just curious.
Anyway, some basic mechanical diagnostics like comp test, leak test and cut open the oil filter to look for metal would be my next move. BT |
Did you put it in base mode to time it. Could be the time chain jumped a tooth, you can check with a valve cover off. It could be ignition module, coil, vacuum leak, FUEL PRESSURE LOW/ lean condition, bad ground. I'm with Blue Thunder and some basic diagnostics are needed.
|
| All times are GMT -5. The time now is 02:54 PM. |
Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.