Spark plugs for fuel injected Honda 90

P

Plan C

New member
It's quite a shock to find that plugs for the new Honda 90's are in the range of $20 each, times four. The plugs, IZFR6K 11E, are a Honda specific plug, and priced accordingly. The IZFR6K 11 plug costs 12.00, retail.

I contacted NGK with the question, "What is the difference?" This is the answer I got from NGK: "The IZFR6K-11E plug has a 10K ohm internal resistor instead of the standard 5K ohm. This is used to help suppress electrical noise that was known to be a problem with the original 5K ohm spark plug in these engines."

Anybody out there have any perspective on this?

Dave
 
I thought $8 a plug was out of line with my 06 f-115 yamaha They said somthing about being a resistor plug? It's a (NGK R LFR6A 11)Since my engine is still under warranty I do what Yamaha says and now I guess it's pretty good buy . That sounds way out of line i'd call around to see what other Honda dealers are charging.
 
Thanks. They may not be the best choice in this case...
I looked at the boats.net site.
9807B-5617C S/PLG (IZFR6K-11E) $34.98 $27.98 4

The $27.98 is the discounted price!

I'm just curious what the "electrical noise" issue is. Is it within the engine, or related to VHF or GPS?

Dave
 
Honda shop manual [maintenance] reads "Check every year or 200 hours,replace every 2 years or 400 hours".Thats twice what most motors require . Most are 100 Hours.
Marc
 
I lost a partly finished post... maybe be some duplication.

I called boats.net to check the price. Turns out their price on the website is incorrect and they are changing it. Retail is $21.44 each plug and their price is 18.22. Roger, I thank you (and probably boats.net does, too) for the link. Whatever, they ARE expensive.

Don't get me wrong, I love the Honda 90. It is an impressive engine in many ways (including instant start in mid-winter!). I'm just taken by surprise with their parts costs. Another example - fuel filter for 2005 Honda 90 is 7.70. For the 2007, price is 13.36. Same filter, except they have the fill pipe at 45 degrees, instead of straight like the earlier one.
Certainly it is Honda's right to charge whatever for parts.

Marc, I recognize that the life of the plugs is doubled, but the cost is eight times as much. Are replacement plugs for other outboards similarly costly?

Can you tell me what the "noise" issue is?

Why is it OB plugs last such a short time (my wife's car with iridium plugs went 100,000 miles before needing replacement. That may be something like 3000 hours) Do plugs last less long due to high rev operation, or some other factor for OB's?

Certainly it would be foolish to skimp on plugs - I'm not intending that. I just want to be better informed.

Dave
 
I did a little Google on the plugs, $20 each is a bargain….eek.gifnot. In the big scheme of things, what’s 80 bucks every couple of years..I’m assuming they last that long or more depending on usage. If you do all your own maintenance and service it all boils down to just parts anyways.
I’m surprised Honda hasn’t figures out an angle that makes changing the plugs a dealer only procedure. smiley_shocked003.gif
 
The noise problem could also be that the spark plug generated noise interferes with the operation of the ignition/injection computer.
 
>The noise problem could also be that the spark plug generated noise >interferes with the operation of the ignition/injection computer.

That is what I am concerned about, Larry. If it was as little as some ticking on the radio, I might not worry about it.

Thanks, Matt.

Mine have gone 200 hours, but 2 years. They look perfect and good gap. I'll put a little more hour on them.

Dave
 
Wonder how many 20% off online parts prices have convenient errors...... You are right on schedule for the second half of your spark plug life . These are the golden years , and yes all the high tec stuff has Iridium plugs . They used to call em lifetime plugs in some applications . Ill bet they will work fine beyond 400 Hrs . Not recommending, just sayin......
Marc
 
Hi Dave,

You are on the right track...Marine engines run at a much higher load and RPM than any standard automobile. Your car typically runs 2000-2500 rpm versus up to 6000 rpm for many minutes or hours at a time with a boat. The throttle opening on a car is typically quite small. This is why the maintenance intervals are much shorter for marine engines. Suppressor plugs are needed to keep RFI at acceptable levels around the engine computers.

You would be wise to use the exact plug specified by the manufacturer. They spend thousands of hours in R&D to get these engines to perform to our expectations. VW wanted $28.00 each for the plugs in the 20 valve turbo engines. I thought $20 each for Opti Max plugs was high. I ended up finding NGK plugs on-line for about 16.00 each. I think it was sparkplugs.com or something like that. I know that the wrong plug will cause everything from minor drivability glitches to major engine damage. I have spent many hours in the shop trying to find phantom ignition problems. One of the first things I do now is check the plug numbers. Get the exact right part.

Hope this helps,

Randy.
 
the Honda 150 also has expensive plugs, replaced at short intervals. I did a search for auto plugs, which turned out to have the same part number. If you bu them from an Internet parts source, they're about $12 ea. That ain't cheap but beats marine prices.

Boris
 
Back
Top