2004 MERCURY 150 EFI WITH 465 HOURS. ALWAYS STARTS WHEN I GO T LAUNCH. AFTR RUNNING WHEN I TRY TO RESTAT IT SPUTTERS THEN STALLS. HAVE TO PUT IN NEUTRAL AND GIVE IT SOME THROTLE TO GET IT TO START. SOMTIMES DIFFICULT TO RESTART. NEW FUEL PUMP INSTALLED COUPLE YEARS AGO WITH NEW LNES AND PRIMER BULB. ALL OEM BY MERC DEALER. ANY IDEAS???
(Added: Serial#0T817858)
Last edited by EuropeanAM; 08-14-2018 at 01:01 PM.
There is a stop screw on the air intake that needs adjustment. Your motor is likely starving for air after warmup. Starts fine cold because it requires more fuel and less air at that time.
You may have to reset idle speed after adjusting the intake shutter stop setting.
Please take a moment to review the Announcements at the top of the Forum, and provide the Required Info with your post. Thanks!
DO NOT attempt any "air adjustments" until we have accurately identified the engine. There are other critical items that need to be checked, and the comments above are based on an engine with the older Laser-Style injection System (yours probably isn't even that design).
Serial Number is best identifier. Thanks!
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
Here are the numbers on my Mercury card
1150413CD 0T817858
Motor runs great. It's on a 2004 Ranger 185VS. 59-60 MPH according to GPS when new and current. Best I ever had was Ohio river running with current at 61.2 GPS. So I would like to say she's running very well. Just trying to restart gives me problems but not always. Did not change the fuel filter this year but this has been going on for several years. Seams to be more of a problem this year. Any help would be greatly appreciated.
Wishin' I was fishin'...
1990 Ranger 374v
1996 175 HP Mariner - Magnum EFI
25p Tempest - A45 model
80 lb 24v MinnKota Maxxum
Humminbird Helix 10
Humminbird Helix 7
Garmin EchoMap 106sv w/ LS
Dual 8' Power Poles
Open your gas cap right before you do a hot restart,,, See if problem goes away,, Having to add throttle to get it to start seems to me a starved for fuel issue vs a starved for air. Clogged or malfunctioning tank vent ?
Good idea to make sure bulb is pumped firm before ALL (every single) start, with the engine at level trim. Adding throttle can (and does) result in maladapt faults for the TPS, so that's not a good idea.
If you continue to have problems, good idea to check the basics (especially monitoring FUEL PRESSURE at startup, idle, 15/30/60 seconds after shutdown, and on a warm restart when acting up.
As I suspected this engine is a later-style (down-draft intake with Motorola 555 style PCM).
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
I'm Back again about this issue. The bulb only stays firm if in a vertical postion when pumping it up. It was replaced with an o.e.m. bulb by mercury dealer. Wondering how to rig it to keep it vertical all the time. No pun intended. Could this be possible problem??? I did open gas cap once on the lake and didn't think it helped restart at all. Just strange. Motor runs very strong once started and it doesn't happen all the time. Just can't pin it down.
Bulb will not stay firm after starting motor as the gas is sucked out of tank, it should feel full of fuel but will not be firm after starting. But if bulb will not pump up firm and stay somewhat firm before starting then could be a problem in fuel system.
Mercury 2002 200hp Carbed Saltwater
OT566776
2002 Cape Horn 22' Bay
Correct. Once you try to crank the engine the fuel pump is PULLING fuel through the line (a Vacuum or low pressure).
This particular "555" based system should be able to restart without issues on a warm start- by simply pumping bulb, throttle at IDLE, key on, turn key to START.
Fuel pressures checked yet?
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
Still having same problem
I went to the lake yesterday 6-24-20 and she fired up ok twice. 3rd time and after I had to give it some throttle to get it to start.
Today 6-25-20 I checked fuel pressure
46 psi at turn of key
stayed steady at 39 for minute after till I bleed the line
checked this 3 times and all same readings
Checked compression
#1 130
#2 120
#3 135
#4 120
#5 140
#6 130
Starting to think my problem is throttle position sensor???
Engine s/n 0T817858
Is there a way I can check the TPS?
What is the p/n for TPS
Should I check fuel pressure while running idle at home?
To start checking components like the tps and other components you really need the service manual to know all the testing procedures and values to look for.
Mercury 2002 200hp Carbed Saltwater
OT566776
2002 Cape Horn 22' Bay
Relocate the bulb to in the bilge out of the sunlight, mount it arrow pointed up more or less, should be able to zip tie it in the starboard rear corner of the bilge, Run new mercury fuel from the bulb to the pulse pump, check the hose in the boat to verify condition, how many pumps required after a hot soak?
Running quickleen every tank?
Thank You Leon Pugh
Fuel pressure readings should be taken:Originally Posted by MEZU50
-At idle
-Under Acceleration
-15/30/60 seconds after engine shutdown.
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
I'm back. Had a tournament yesterday. Started just fine and ran great like always. Fished for couple hours then tried to restart. Motor tries to run but stalls out. This has been going on for 10 years or so. Seems like past couple years been real problem. I'm starting to believe it's because of outside air temp 80 degrees or warmer. Doesn't seem to do it in the fall cooler weather. Only way to restart it is to give it throttle in neutral. In past all I had to do is give it a little throttle and that's why I never took it in now I have to give it a lot of throttle hoping for it to start. I know I shouldn't do this but only way. Is there a outside air temp sensor that could be causing this?
There is an air temp sensor, so it's possible.
Also possible that it's RICH all the time for some reason (and the engine is more tolerant when it's COLD and needs extra fuel). Some of what we're looking for in tests suggested above/earlier.
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
Just to be clear checking fuel pressure is at high pressure fuel pump valve stem port correct?
Can I take readings at home running idle and then engage prop and increase throttle or does it need to be on lake running?
After many years with this problem neutral and give throttle you said "Adding throttle can (and does) result in maladapt faults for the TPS, so that's not a good idea" I did read today you can reset computer by turning kill switch off/on 5 time with key on. Might my computer need reset with so many years creating faults?
I do very much appreciate you working with me. All marinas are minimum 4 weeks out and my luck is they won't be able to replicate my problem.
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