Please help! 2007 optimax 150 problems

[Dhott]

Hey guys. I’m looking for an experienced optimax expert that can help me diagnose my rough idle problem. I’m willing to pay. Long story short I got a reman powerhead from mercury put on earlier this year. Ever since I’ve had a problem with it idling really rough. Can someone please walk through diagnosing. The shop can’t figure it out and it’s not throwing any codes. I’ve done a lot to it so far with no improvements. I would like to talk with someone who knows their way around an optimax to help me figure it out. I’m desperate. Again, I will pay if you help me solve the problem! I’m sure if someone who knows optimaxs could figure it out pretty easily. I’m just tired of the usual vague answers from people who are just guessing. Thanks so much in advance!

 

[vroom ZOOM]

Hey guys. I’m looking for an experienced optimax expert that can help me diagnose my rough idle problem. I’m willing to pay. Long story short I got a reman powerhead from mercury put on earlier this year. Ever since I’ve had a problem with it idling really rough. Can someone please walk through diagnosing. The shop can’t figure it out and it’s not throwing any codes. I’ve done a lot to it so far with no improvements. I would like to talk with someone who knows their way around an optimax to help me figure it out. I’m desperate. Again, I will pay if you help me solve the problem! I’m sure if someone who knows optimaxs could figure it out pretty easily. I’m just tired of the usual vague answers from people who are just guessing. Thanks so much in advance!

Not a real expert, but I have worked on opti's. is it doing this:

also, what year is it, and model? some of the opti's had coil and injector recalls. Those things won't throw a code. A lot of things on an opti won't throw a code, but make it run like garbage.

EDIT: just saw the year and model in the description. You are in the possible years for failed coils. Is your serial number in the range 1B421465–1B776910?

 

[Dhott]

It’s doing something similar. Yes 2007 150. I already replaced one coil which was causing surging through the higher rpms. It still idles really rough though but runs fine when I give it a little gas. Was your issue a coil? Here’s how mine idles

 

[vroom ZOOM]

It’s doing something similar. Yes 2007 150. I already replaced one coil which was causing surging through the higher rpms. It still idles really rough though but runs fine when I give it a little gas. Was your issue a coil? Here’s how mine idles

Does it idle ok if you run for 15 mins and then return to idle? There are only really two things that can cause this, a faulty TPS, or in the most common case, a weak battery/connections. Probably the latter in your case. Measure the battery voltage with the engine idling right after starting at the relay in the motor.

 

[vroom ZOOM]

It’s doing something similar. Yes 2007 150. I already replaced one coil which was causing surging through the higher rpms. It still idles really rough though but runs fine when I give it a little gas. Was your issue a coil? Here’s how mine idles

link missing

 

[Dhott]

Here is the link. No it always idles bad. I’ve measured the voltage. What’s it’s supposed to be? I thought I had the issue narrowed down to one of the diaphragms in the fuel rail

 

[Dhott]

Here is the link. No it always idles bad. I’ve measured the voltage. What’s it’s supposed to be? I thought I had the issue narrowed down to one of the diaphragms in the fuel rail

 

[Dhott]

Sorry. Here is the video

 

[Dhott]

I should give you some more information. I put new plugs in it. Checked the tracker diaphragm and fuel regulator diaphragm. I didn’t see any tears or holes in the diaphragms but the fuel regulator diaphragm was a little deformed. I checked air/fuel pressures and they looked to be right on at 80/90. I’m getting a little mist of fuel out of the air side schrader valve.

 

[vroom ZOOM]

I should give you some more information. I put new plugs in it. Checked the tracker diaphragm and fuel regulator diaphragm. I didn’t see any tears or holes in the diaphragms but the fuel regulator diaphragm was a little deformed. I checked air/fuel pressures and they looked to be right on at 80/90. I’m getting a little mist of fuel out of the air side schrader valve.

That sounds different than mine.

A little fuel fumes is ok in the air rail, but a lot is not. Basically you should not be able to see any fuel in the air rail. With the engine running, press on the air schrader valve, there should only be air. No visible fuel. Your air and fuel pressures are alright. There are two valves, one to control air pressure relative to the atmosphere (this one is good since you are getting 80 psi) and one that controls fuel pressure relative to air pressure (this one has a pinhole). DON'T take apart the air pressure regulator. If you do, you will be in the great activity of throwing curse words and trying to stuff an 80lb spring back in. The spring in the fuel pressure regulator is much softer.

You can test for a pinhole by removing the rail, plugging the fuel discharge, and then using a fuel line bulb, pushing fuel into the fuel inlet. Most likely you will see fuel start coming out of the air rail if there is a pinhole.

Also worth mentioning, that i would recommend getting the injectors cleaned if you have it all apart. Get the regulator fixed as soon as possible. If it starts leaking a lot, you are going to be dumping a lot of fuel into the cylinders - this can cause a runaway.

 

[Dhott]

Thanks for the help! My particular engine doesn’t have the normal air pressure regulator. I think mine is the version 2 or something like that. It doesn’t have the diaphragm or spring like the fuel regulator or tracker valve. I have the fuel and air regulators on the port rail and the tracker diaphragm on the starboard rail. So with my situation you would say that my fuel regulator is the problem correct? Not the tracker? I’ll attach a picture of the fuel regulator diaphragm

 

[vroom ZOOM]

the one on the right is the fuel pressure regulator. The one on the left is the tracker valve. both have the fuel and air separated by a rubber diaphragm. either could be leaking. You could do the test I mentioned before, by pressurizing each fuel rail independently. Thankfully the tracker valve and the fuel pressure regulator are on different rails, so you can pressurize them independently and rule out the bad one.

 

[Dhott]

Thanks a lot. Here are videos of the air and fuel pressures. Do they look right to you?

 

[Faztbullet]

Pull the plugs as you can hear a cylinder clear itself and RPM increase. Could be a injector flooding or lean. I would send em off to have cleaned and flow tested(Brucato)

 

[Dhott]

The plugs all look the same to me ever since fixing the bad coil I had.

Pull the plugs as you can hear a cylinder clear itself and RPM increase. Could be a injector flooding or lean. I would send em off to have cleaned and flow tested(Brucato)

 

[Dhott]

That sounds different than mine.

A little fuel fumes is ok in the air rail, but a lot is not. Basically you should not be able to see any fuel in the air rail. With the engine running, press on the air schrader valve, there should only be air. No visible fuel. Your air and fuel pressures are alright. There are two valves, one to control air pressure relative to the atmosphere (this one is good since you are getting 80 psi) and one that controls fuel pressure relative to air pressure (this one has a pinhole). DON'T take apart the air pressure regulator. If you do, you will be in the great activity of throwing curse words and trying to stuff an 80lb spring back in. The spring in the fuel pressure regulator is much softer.

You can test for a pinhole by removing the rail, plugging the fuel discharge, and then using a fuel line bulb, pushing fuel into the fuel inlet. Most likely you will see fuel start coming out of the air rail if there is a pinhole.

Also worth mentioning, that i would recommend getting the injectors cleaned if you have it all apart. Get the regulator fixed as soon as possible. If it starts leaking a lot, you are going to be dumping a lot of fuel into the cylinders - this can cause a runaway.

By the way as soon as I press the air schrader valve the engine dies. Should I be able to press the valve and the motor will keep running?

 

[vroom ZOOM]

By the way as soon as I press the air schrader valve the engine dies. Should I be able to press the valve and the motor will keep running?

Its not going to be super happy. You are dropping the air pressure effectively, and then there is no pressure to inject the fuel air mixture into the cylinder, so it dies. BUT, like faztbullet mentioned, get those injectors cleaned regardless. It's part of regular maintenance and may clear up your problem. Two places are at Tony Brucato or Don Weed at european marine.

 

[vroom ZOOM]

Thanks a lot. Here are videos of the air and fuel pressures. Do they look right to you?

 

[Dhott]

Thanks I was wondering about that. I also thought it was strange how fast the pressure drops after the high pressure pump shuts off when turning the key. At the very end of the video

I don't like the way the fuel pressure drops so quick after shutting the motor down... let me check on my opti how fast it drops off, I'll report back.

 

[vroom ZOOM]

The fuel pressure video ends before fuel pressure drops off fully. The area of interest is when it goes from 10 to 0 psi. The part where it drops off from 90 to 10 psi is because the fuel pressure is dependent on the air pressure. If the air pressure drops off that fast, then the fuel pressure will follow it with the 10psi difference. The air pressure dropping off is suspect of a bad air pressure regulator. Make a video of the air pressure and fuel pressure dropping off to 0, that may help explain some things.