Mercury 60 EFI hard cold start

[sutor623]

Recently got a 2007 Mercury 60 EFI. Had it out 4 times and she seems to be a reliable engine. The previous owner said the only thing he did in the 3 years of owning it was change oil and water pump.

We took it for a test run, it started right up, and ran great for our test run. He seemed like an honest guy and didn't think the engine had any issues. I do know that it has sat for months at a time with ethanol gas in it.

I got all the old fuel out of the tank and put fresh fuel in it.

Next time I took it out it was about 40 degrees. Tried to start the motor without advancing the throttle, and it wouldn't turn over, but was cranking fine. Lifted the neutral idle lever, she started and if I backed it back down she stalled and quit. Let it warm up for 3 minutes at about 1500-2000 rpms, set her back to idle and idled perfectly. Gets out of the hole strong, runs WOT perfectly.

Next time out she started at one flick of the key.

Anyways, I ended up checking compression and got 180 in all 4 holes out of a cold motor. (These spark plugs are a B to get to) so I went ahead and put new plugs in. While I had the ignition plate off and spark plugs out, I went ahead and took the valve cover off and adjusted all of the valves.

Last time out same deal, had to convince her to start. It was 32 degrees out. We fished for 6 hours. After initial warm-up she started up all day without a single issue. Ran strong, felt great.

I am not sure when the fuel filters were replaced, but I am thinking that is a good place to start. Any suggestions or ideas guys?

 

[sutor623]

I thought there was a fuel filter on the high pressure side but couldn't locate it. I cAn hear my fuel pump engage when I turn the key.

 

[Sylva-Ranger]

Usualy these engines start just touching the key.........One of
The first thing to check is the EFI fuel pump pressure (about 37 psi if i remember ).

 

[sutor623]

Usualy these engines start just touching the key.........One of
The first thing to check is the EFI fuel pump pressure (about 37 psi if i remember ).

Thanks, I will have to pick up a high pressure fuel gauge.

I hear ya about the touch of the key, because after she has that first warm-up all I have to do is touch the key.

I may have been a little bit hasty on my start-up, not being used to the EFI motors. I don't think I waited the 2-3 seconds for the fuel pump to turn on and back off. Maybe that was part of my issue.

 

[Mohawkmtrs]

What is the viscosity of the oil in the crankcase? It was quite cold when you tried to start it.

 

[sutor623]

Indeed!! The motor calls for 25-40 for all temps, or 10-30 for 40 degrees and below. I had 10-30 in there

 

[Mohawkmtrs]

Well, it's not the viscosity of the oil that's the issue.

I think you may be onto something regarding your starting procedure.

 

[sutor623]

I think you may be right. One other factor that may play into this is the fact that this motor has a jet drive lower unit. This means that there is ALWAYS a load on the engine, even when in neutral, since there is no gearcase, just a jet impeller on the driveshaft.

Sooooo I did things a little differently this morning. It was 28 degrees out. I got the boat in the water, trimmed it up just enough to let the exhaust and jet be coming out of the water(instead of being tucked in hard like these jets like to run.) Turned the key on and let the fuel pump cycle. Left the neutral idle lever alone. Spun the starter about 3 second, no start. Did it second time, no start. Third time she fired right up and idled perfectly. Took about 2 minutes for the thermostat housing to reach 120 degrees and it just stayed there.

After warm up it will start with a touch of the key. I am thinking a combo of me not letting the fuel pump cycle, the temperature, and the load on the engine at startup are what made this engine a little tough to start.

Sound legitimate? I'm sure the fuel filters and VST could use a cleaning, but other than that She's good to go.

 

[sutor623]

Well sylva, your advice to check for fuel pressure was spot on. I had too HIGH of fuel pressure. There was a blockage at the regulator. My guess is the mixture was too rich and the motor had a hard time compensating for it. If anyone is interested in how I resolved the issue check out this link. Thanks guys!!
http://forums.iboats.com/forum/engi...y-ever-hear-an-efi-act-like-this-before/page2