In another thread I included a short off-topic lament about access to the spark plugs, and I got corrected: So I looked around and I did find some threads like this one describing tools and techniques needed to replace plugs in the NHW20 with the cowl in place. Have people done that with NHW11s also? Does it turn out to be more or less bother than moving the cowl? Is there a thread with pics? Thanks, -Chap
Hi Chap, Yes, the spark plug replacement process is basically the same. I am not aware of an NHW11 thread with pictures. Remove the relay box mounted to the cowl to improve your access to the spark plug igniters and the spark plugs. Depending upon the spark plug ratchet wrench that you are using, you'll need to employ various extension lengths. I recall that I used a 6" extension as well as a 4" extension combined with a 1" extension (resulting in 5" length.) Assuming that you have the correct length extensions available, this is easier than removing the cowl. Good luck.
I changed my plugs about 2 years ago and don't remember anything remarkable. The old plugs looked a little worn on the electrode but otherwise, unremarkable. I really don't member anything other than the plug socket coming off the socket extension and being a little coy to noodle out. Bob Wilson
I'm sure it is not absolutely necessary to dismount all that hardware for plug access. However, since one will probably go in only rarely, why not open 'er up and change the PVC valve at the same time? Then you're good for another 100k. Also this level of disassembly allows you to clean out some 'leaf litter' that you probably didn't know you had. And to consider whether to protect certain orifices against small rodent entry with metal wire mesh. Bob you need to put some used chewing gum on those rachet extensions...
Changed the plugs on my '02 Prius with 111,000 miles today, very easy job took about 20 minutes. Here are a couple of pictures of the old plugs.
