Spark Plug diagnostic after 200 hours (or so)

[capnlee]

75hp E Tec
XD100 oil on reduced oil setting
E75DPLSD
05134363

I don't know exactly how many hours I have on the motor, but the last time I took it in for an update (1 year ago) I had about 75 hours after 8 months. I figure I'm somewhere over 200 now. While I was out this weekend the motor would sputter a little bit while trolling, but it wasn't consistent and would start running smooth again after a while. It did this a little bit on my last trip but seemed worse this time. At the end of the day I started to head back, and when I gave the motor gas, it choked and sputtered and coughed up a bunch of white stinky smoke. I backed off the throttle and it idled OK, so I gave it gas again. It started out missing but then evened out and ran fine all the way back to the ramp. I never got any alarms or warning lights. I pulled the top plug and here is what it looked like:



I'm hoping some of the gurus can tell what is going on by looking at the plug. It looks like a lot of carbon buildup and the center electrode is burnt more on one side. I'm assuming the plugs were indexed correctly. The lines drawn on the plugs are between the 9 O'clock and 12 O'clock position.
Question: I troll a lot. Will this cause the plug to foul sooner?
Should I decarb before changing plugs? (I'm guessing yes).

Note: I am not complaining. My motor has been trouble free up to this point, and plugs are a pretty cheap fix. I'm just trying to gain a little more insight as to what is going on inside my motor.

P.S.--Can anyone tell me if there is a new map for my motor?

Thanks!

[Huey]

Hi, it is time to replace the plugs. With your age engine the ignition system is a doulbe strike system at low speeds so for every hour you spend at low RPM the plug fires double. What we have seen here in OZ is that on engines that idle or troll alot we are getting about 150 hours out of the plugs. Also make sure the engine is reaching operating temp at low speed-easy to check with the laptop and your engine should have revision number 90187 which came out with the in line update on 07/21/2006.

The 2008 model engines have improved the ignition system to an inductive system with a fast rise time so from what I was told when I was at the factory last year you can expect over 300 hours no matter what RPM you run at. This system is patented and talking to the R & D guys at BRP is quite an acheivement and just one of a few improvements for 2008 models.

Put new plugs in, make sure they are indexed and you will be fine.

Cheers,

Huey.

[Bassmeister]

[SEAHORSE]

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by capnlee &raquo;</TD></TR><TR><TD CLASS="quote">75hp E Tec
My motor has been trouble free up to this point, and plugs are a pretty cheap fix. I'm just trying to gain a little more insight as to what is going on inside my motor.

P.S.--Can anyone tell me if there is a new map for my motor?

</TD></TR></TABLE>

There is a map for your motor called Inline Update and another one to make your motor just like a 2007 model. Your dealer will have to determine if your motor has it or not by using the laptop.

Your plug shows excessive wear at the gap, and that is usually from the motor not reaching the proper temperature at idle, just as Huey mentioned. Have the thermostat checked and have the dealer call the factory about any changes that the pressure relief valve might need. The only way to check for proper idle temperature is to use the laptop.

If your dealer is not helpful, contact Evinrude customer service.

[gcmarshall]

I had the same problem, and I changed the thermostats & pressure relief valve which helped me get to the correct operating temp, and I switched to XD100. So far, I am getting 300+ hours out of the plugs I would say, compared to about 150 before....

I haven't done the inline update as yet but plan to soon...(didn't do it, since I had some electrical trouble with the engine, and didn't want to risk the update screwing up and needing a new EMM)

[capnlee]

Thanks for the info guys. I will change plugs next time I'm out--I'm keeping the boat stored at the lake--it's cheaper to store it than tow it. The first chance I get I will have the updates done.