1st spark plug failure

[Marvin willis]

Went out to get the boat ready and when I tried to start the motors only one started. Pulled the plugs and found 2 of them had weak spark so I went to auto zone for new plugs. Started right up with new plugs. Just curious if anyone has tried the auto lite plugs that are 1.99 a plug?

 

[Bruce]

I am curious how often you change your spark plugs?

I change them every year. For the past two years I have found Advance Auto Parts coupons that let me buy a full set of the factory specified spark plugs for around $20. I keep a spare set of gapped plugs in the boat in a dry bag. I check the gap and install the spare set when I change the oil.

 

[itsdgm]

I do the same as Bruce. I replace every year.

 

[Marvin willis]

Me too except i don't have a spare until now. Advanced told me they couldn't get that plug. Cr9eb

 

[Big Shasta]

You've gotta love a boat that has simple needs. Yearly change is cheap insurance.

I put in the iridium's never had a plug issue. I think it had been 2 years when I sold the boat. I just couldn't see tossing good plugs. I did always have a set onboard with the tools to change them and some anti seize.

DO NOT forget the anti seize and don't over tighten them. I would go 1/4 - 1/2 a turn after finger tight.....depending on how it felt.

 

[Bruce]

Here is the link to CR9EB at Advanced. When I went to the website a box popped up offering a 20% discount for my email address. Once you are on the mailing list they will send out better coupons. I place my order online to get the discount then pick them up in store. My local stores stock CR9EB but if they do not have them immediately available they call when they are ready.

 

[Marvin willis]

Now that just pissed me off. They told me they couldn't get he plug. Plus I thought I was getting a deal paying 7.99 a plug. I think I paid 11 a plug last time

 

[Morrowcat]

Ngk plugs are better quality then autolite, plus if you notice that the Ngk plug threads are shiney and autolite are black, Ngk puts a nickel plating on the threads as a built in antiseize. According to Ngk they suggest not using antiseize, especially in aluminum, as it's possible to over torque them when not using a torque wrench. Although I do understand why some do considering the marine environment.

 

[Big Shasta]

Ngk plugs are better quality then autolite, plus if you notice that the Ngk plug threads are shiney and autolite are black, Ngk puts a nickel plating on the threads as a built in antiseize. According to Ngk they suggest not using antiseize, especially in aluminum, as it's possible to over torque them when not using a torque wrench. Although I do understand why some do considering the marine environment.

With the incidents of plugs frozen and busted off in heads on these boats, I would use antiseize no matter what,

 

[Morrowcat]

@Big Shasta ...thanks for pointing that out. I should have stated I wasn't implying not to use antiseize but just stating what ngk recommends.
Edit: I suppose this is also why adhering to specified torque value is important?

 

[Gym]

Whereas I only put 20 - 25 hours on per year I have adopted a once every other year change on the plugs. I did this for the first time last year. The plugs I removed after 2 seasons looked great so I kept them on board as emergency spares. I did anti seize them well so no problems with removal. I still do annual oil changes at the end of each season.

 

[ruztew]

I read something about the NGK plugs not needing antiseize and applying it can cause the plugs to get over tightened ......


http://www.ngksparkplugs.com/pdf/dyk_5points.pdf

 

[Morrowcat]

I've never used antiseize on the automotive side including my race engines and never had an issue but I am no expert marine so I won't comment and leave that to the people with first hand experience with issues.

 

[Scottintexas]

the older MR-1 engines have a history of having the #3 plug becoming seized and end being snapped off when people try to remove them.

I'm sure the NGK advice is correct under normal circumstances but while the MR-1's excels in many ways the #3 plug issue causes the general rule to tell everyone to use antiseize although I don't think we've heard of anyone having a seized plug on a 1.8L

 

[tdogg]

I used to replace the plugs every season but I have since stopped. I just carry a spare set on the boat. I can swap them out if needed on the water. I do put antiseize on the threads and probably should check that they are not seized during my winterization this year.

I have the iridiums installed now and have not seen any issues even with fogging the motors for two winters now. I generally fog until the motor rpm slows, then with the lanyard pulled turn over the motor while spraying down the intake of each cylinder. I haven't changed them and they are still running strong. It takes a few minutes every spring to burn out the fogging oil but the motors usually clean out without issue.

I think the iridiums part number is CR9EIX.

Cheers,
Toby

 

[Trm1765]

I have almost 300 hours on my factory plugs and can still get over 50mph.. Only topped out at 54 when it was brand new. I pulled them out and looked at them last spring and they looked awesome.. Maybe next spring I'll think of changing them again.