changing sparkplugs in OptiMax

[1shooter]

I searched previous threads as I know it has been disucssed before but I can not find it. I think it was "Perchjerker or REW" that posted detail intructions on how to change this plugs in a 150 opti.

I believe they even listed the tools they used.

If anyone has this or know please let me know.

[jimcar]

Guys use pieces of garden hose to remove and replace both lower plugs. gotta loosen them first. I just take the four bolts out of lower cowling, then split the back which allows easy access to plugs with plug wrench.

[1shooter]

Anyone find the details on this?

Perchjerker, REW or EBIJACK?

[fishin4alivin]

I too would like to know. I need to replace the plugs in my 135 Opti and if someone can tell me how to go about doing so and the tool needed that would be greatly appreciated.

[staylor]

...on a 150 Opti, and since I'm lazy I don't split the cowl. You need a 3/8 drive plug socket with a built in universal joint. I bought mine from JC Whitney. You can also make do with a standard plug socket and a separate universal. I use 2 short extensions on this, one of which allows some flex in the extension to extension connection. First step is to pull the plug wires- and for the lowest plug on the port bank you will need to pre-bend a piece of heavy coat hanger wire to make a puller. You slip this down below the rubber connector and wiggle/pull on it till the connection comes off. Then you assemble your socket and extensions and fish them around until you've got them on the plug. Get the plug out a couple of turns and remove the socket. Then take a 12 inch long piece of fuel line hose- the automotive kind- not the heavy outboard type- 5/16 ID- and snake this down and push it over the plug insulator. Sometimes this hose needs a bit of grease at the end to get it on the plug easily- and I actually put a thin coat on the outside of the hose so it doesn't drag on anything while I'm turning the plug. Reverse this procedure to install the plug- using the hose to get the plug started and down a few turns so you know its not cross threaded. All of this took me an hour to work out the first time I changed plugs- now it takes only about 5 minutes of careful work to get that low plug on the port bankl changed. All the other plugs are relatively easy. Do this only on a cold engine on a sunny day so you can see the low plugs.
Doug

[ebijack]

i cut down ( cutoff wheel) a hexed spk plug socket to where it was just long enough to grab the plug hex and then used a open end wrench on the plug socket. (like socket in pic..hexed) http://www.mytoolstore.com/sk/sk03223.html
then use a cut down old sparkplug boot. use this to remove and install your plugs.
some reccomend to index the plugs ( i do) for any high pressure injection motor. does make a difference on how much of the fuel gets burned and cyl temps on dyno testing. easy to do, just mark with a marker on the insulator of the plug where the open part of the electrode is and try to get that as close to where the injector is.
hope that helps

[sparkyaber]

On my 200 opti, I removed the coils to allow more room to work on that lower left plug.

[Redbone]

Get a 12 inch piece of rubber hose (auto store) that fits snug on the plug. Plug socket that has a universal on it. 1 short and 1 medium extension. And a 3/8 drive ratchet. I like my ratchet to have a angled handle on it also. Tools can be had a Harbor Freight.

Break plug loose with socket. Place hose on plug, twist to remove. To replace - put plug on hose, place back in hole, twist till tight, then tighten with socket.

Some spots you need to fish the tools between hoses. On the middle port hole you might need to unplug the connector to the injector .

Not too hard but takes some time.

Robert Piette

[1shooter]

I changed the plugs today and it was not that bad. The univeral jointed plug socket and the hose were an absolute must.

I did run across something that has me scratching my head. The old plugs were a NGK IZFR5G which is not what the owers manual references.

The correct ones are a NGK PZFR5F.

The electrode on the ones I pulled out were real skinny too. Does anyone know what the difference is?

[staylor]

Opti's have had several types of plugs. My 150 came new with plugs that were a different number than called for on the sticker on the block and in the manual. When I went to buy a new set the dealer had a new P/N superceding the ones in the motor. This was the "skinny" electrode iridium plug P/N 1ZFR5G @ .03 gap. The older plug in the 150 that was superceded by the Iridium plug was the PZFR5F @.044 gap. So I think you may have put in the older/superceded plug. The good news is that the older plug runs pretty good, but on my motor did not idle quite as nice as the Iridium plug- which costs a lot more. Whenever I buy plugs for a Merc I give the motor S/N to the dealer and let him look up the most recent plug recommendation in his computer- along with the gap required. In the case of the Iridium plugs its probably a good idea not to attempt to gap them unless you are really careful- since the center elctrode is very brittle.
Doug

[1shooter]

Opti's have had several types of plugs. My 150 came new with plugs that were a different number than called for on the sticker on the block and in the manual. When I went to buy a new set the dealer had a new P/N superceding the ones in the motor. This was the "skinny" electrode iridium plug P/N 1ZFR5G @ .03 gap. The older plug in the 150 that was superceded by the Iridium plug was the PZFR5F @.044 gap. So I think you may have put in the older/superceded plug. The good news is that the older plug runs pretty good, but on my motor did not idle quite as nice as the Iridium plug- which costs a lot more. Whenever I buy plugs for a Merc I give the motor S/N to the dealer and let him look up the most recent plug recommendation in his computer- along with the gap required. In the case of the Iridium plugs its probably a good idea not to attempt to gap them unless you are really careful- since the center elctrode is very brittle.
Doug

Is there some where online you can look this up?

[Brekk]

I took mine out the other day when winterizing my 175 opti. It was quite easy. Didn't remove anything. Use a 1/4 inch flex head ratchet and a couple of short extentions, 1" and a 2" inch. Put all of them back in with my fat fingers. I like to make sure they turn freely when installing. Don't forget to torque them. I'm not going to put the new plugs in until I run it once or twice with the old ones, until it cleans the oil out of the cylinders from winterizing.

[1shooter]

I took mine out the other day when winterizing my 175 opti. It was quite easy. Didn't remove anything. Use a 1/4 inch flex head ratchet and a couple of short extentions, 1" and a 2" inch. Put all of them back in with my fat fingers. I like to make sure they turn freely when installing. Don't forget to torque them. I'm not going to put the new plugs in until I run it once or twice with the old ones, until it cleans the oil out of the cylinders from winterizing.

Your must be a littlw different than mine because there was no way I was going to get the bottom left plug started with out the rubber tube.

Now I'm wondering if I put the best plug in.

[staylor]

I know of no place on line that would have this info- only the computer at the dealer.
Doug

[1shooter]

does anyone know the differences in the plugs?

[jimcar]

You need the iridium plugs in that motor. They burn cleaner, last longer , and dont foul. Go on bassboatcentral and check with Don at European Marine. Make sure you gap them .032-.033. Do not put gap tool between tip and electrode. Use pliers or other tool on outside of electrode to gap.

[1shooter]

You need the iridium plugs in that motor. They burn cleaner, last longer , and dont foul. Go on bassboatcentral and check with Don at European Marine. Make sure you gap them .032-.033. Do not put gap tool between tip and electrode. Use pliers or other tool on outside of electrode to gap.

Both plugs are iridium.

[staylor]

...a double platinum plug if I recall, with a small diameter platinum center and a platinum ground electrode. The center electrode is larger in diameter than the fine wire iridium electrode, but smaller than the older copper electrode plugs. The thin iridium electrode wire is said to do a better job of burning off fouling deposits, and after running both plugs in my Opti I agree with this- the difference is small, but was noticeable on my motor after prolonged trolling. I've been running a gap in the .03 to .031 range, and after a season of use the gap appears unchanged. I may try jimcar's suggestion to try a slightly wider .032 to .033 gap next time I have the plugs out. I set gaps with the iridium plugs with old fashioned flat feeler gages- with the outer electrode moved until a .030 gage will "go", with no drag, and an .031 gage will "no go". Be very careful with the iridium wire- its brittle and will snap off if you try to bend it even slightly- or drag a wire gage across it- I found this out the hard way.
Doug

[jimcar]

Yes the P stands for platinum and the I for iridium. Be careful gapping those plugs. I use a small plier to grab outside of ground electrode and bend slightly to open gap. Then carefully measure gap. Good luck!

[1shooter]

Yes the P stands for platinum and the I for iridium. Be careful gapping those plugs. I use a small plier to grab outside of ground electrode and bend slightly to open gap. Then carefully measure gap. Good luck!

Great! I spent $60 on plugs and installed them and they are the wrong ones.