Opti low rpms

**vnemous** · 01-31-2018, 02:51 PM

The iridium spark plug will supersede and back fit the platinum spark plug. The platinum and
iridium spark plugs can be intermixed and used in the same engine.
The new spark plug is a running change for the 2003 model year. This bulletin is to inform
you of its presence in advance of pending service manual updates.
Platinum spark plug NGK PZFR5F-11, Mercury P/N 33-855672 1
SUPERSEDES TO
Iridium spark plug NGK IZFR5G, Mercury P/N 33-889597 001
Spark plug gap
Platinum PZFR5F-11 ––––––– 1.1 mm (.043)
Iridium IZFR5G –––––––––––– 0.8 mm (.031)

**Loxboy1** · 01-31-2018, 07:00 PM

I have izfr5g gaped at .031

**vnemous** · 01-31-2018, 07:04 PM

I posted that from the service bulletin so................

**flabum1017** · 01-31-2018, 07:55 PM

At this point, you are best off having your friend scan the computer checking the TPS setting, make sure the temp senders are reading accurately (I had one that would read 140 when it was dead cold), check all the sensors to make sure they are reading accurately, check the 5 volt rail etc..... One note about sensors and alarms..... you can have a sensor or TPS not reading accurately and give you no alarm if they are within the expected "range" of the sensor. Let's say you have a temp sensor and it reads 140 when the engine is cold.... the alarm will not sound because the sensor is putting out within it's expected range as opposed to a shorted sensor which will throw an alarm. So just scanning for codes most times will not lead you to the source of the problem. If your buddy is too busy, I may be able to swing by saturday and put my scan tool on it for you so we can eliminate the sensors and check for codes and such.

Do you still have the blown engine to swap parts with?

**half fast** · 01-31-2018, 08:53 PM

That gap setting is not what mercury says but I will try and get the most current bulletin . I love trying to communicate with all the internet experts !

**Loxboy1** · 01-31-2018, 08:59 PM

Originally Posted by flabum1017

At this point, you are best off having your friend scan the computer checking the TPS setting, make sure the temp senders are reading accurately (I had one that would read 140 when it was dead cold), check all the sensors to make sure they are reading accurately, check the 5 volt rail etc..... One note about sensors and alarms..... you can have a sensor or TPS not reading accurately and give you no alarm if they are within the expected "range" of the sensor. Let's say you have a temp sensor and it reads 140 when the engine is cold.... the alarm will not sound because the sensor is putting out within it's expected range as opposed to a shorted sensor which will throw an alarm. So just scanning for codes most times will not lead you to the source of the problem. If your buddy is too busy, I may be able to swing by saturday and put my scan tool on it for you so we can eliminate the sensors and check for codes and such.

Do you still have the blown engine to swap parts with?

i donot have the motor itself but i stripped it and have most of the parts. I donot have any temp senders or map sensors though. Let me know what you need for compensation, i appreciate the help. We have plans to go to whiskey creek saturday with the boat. I launch at harbor town so if it would be easier to meet up there since your in FT Laud let me know.

Im running out of things to check/replace so it has to be electricle at this point hahah

**Loxboy1** · 01-31-2018, 09:01 PM

Im not saying you are wrong. I just went with what the pdf manuel i downloaded said and what i saw on most fourms. I will open the gap and try it, it wont hurt anything to have a larger gap. It will eather run better or worse lol.

**flabum1017** · 01-31-2018, 09:17 PM

The marina I work at is just a little north of there if you want to meet there. I'm the first canal past the 17th street bridge on the west. give me a time and I can schedule my day..... oh, and no charge for a quick scan for S&F members LOL

**flabum1017** · 01-31-2018, 09:21 PM

Quick question..... does it feel like it's bogging? does it get to a certain throttle position and even though there's more throttle left, you can't get more RPM? When I say throttle, I mean throttle at the helm, not the extra travel at the TPS

**flabum1017** · 02-01-2018, 12:06 AM

Originally Posted by FMP

Just read the 73 brochure for the F233 with twin 165 weighs about 3800lbs. That's a second hand off the web number, I would have guessed more.

wrong thread LOL

**vnemous** · 02-01-2018, 08:19 AM

Originally Posted by half fast

That gap setting is not what mercury says but I will try and get the most current bulletin . I love trying to communicate with all the internet experts !

Well I copied that portion of the service bulletin off my Mercnet as we are also a Premium Mercury Dealer. If there is something more recent I didnt see it but I shall look again.

**Loxboy1** · 02-01-2018, 05:15 PM

Wow thanks bud i really appreciate that, you sure i cant buy you a case of beer or somthing?. As for the throttle thing. I honestly dont remember feeling it get to a certian rpm and stop while i keep advancing the stick. Id have to run it to see.

What marina do you work at? Lauderdale marina?

should i open the spark plug gap to 0.41??

**flabum1017** · 02-01-2018, 06:03 PM

If you are running the iridium spark plugs, leave them at .031 as per the service bulletin Venomous posted. I work at 1st Performance, right next door to Lauderdale Marina.

Let's see if I can help you before you get me a 12 pack ;-). I mostly work on diesels and gas inboards and I/O's here, but have some experience in the Opti's. Give me a pre-2000 Lemmonrude and I'll fix it in a heartbeat.

Since that motor is new to you, it could be anything from a clogged filter, too much fuel pressure, injector not in specs, tps, map. ....... pretty much anything. My buddy had the same issue, turned out to be a coil..... it actually ran pretty smooth on 5 cylinders.............