Just want to find out if anyone personally replaced the spark plugs on their GX460.
Were there any complications removing the 8 spark plugs, ignition coils, or air filter assembly? Which brand of spark plugs is better - Denso (OEM) or NGK Laser Iridium? Any knowledge will be greatly appreciated.

 

Bummer you got no replies. I haven't done it personally, but it sounds like you've got the basics. It seems like access to a couple of the coil packs was tricky on the 4.7 V8, and I assume there may be similar issues on the new one. I did read on this board a while back that someone found some oil in the spark plug well, so it's worth checking on the condition of those seals when you dig in there.

Personally, I'd stick with OEM Denso's.

 

Here you go.

 

i realize that this is a revival of a very old thread, but someone may find it in the future.

I swapped out my plugs a few months ago at 57k miles. Probably wasn’t necessary - they still looked pretty good - but I was more curious to ensure that I didn’t have any oil on the plugs.

the process was time consuming but not overly tedious. I used a variety of extensions and swivel joints. You need to remove the plastic engine covers, air box and piping, some small bolts in order to move connectors out of the way, etc. I don’t recall any of the plugs giving me any trouble to access them.

my OEM plugs were VERY tight and I was really concerned about breaking them in the engine but thankfully this didn’t happen. There was some sort of thread sealant on them.

make sure to properly torque the new plugs.

you can definitely do it if you’re comfortable with sockets and have the right extensions, joints, etc.

 

... what JonGX said ^ ... but be patient on removal ... note the torque (effort) required during removal ... if the torque (effort) required increases at any point while removing, reverse direction for a few turns to unload the threads, and then continue to remove ... repeat as many times as necessary ... debris between the plug threads and the threads in the head can cause the spark plug to bind, so if you do not reverse direction to free up the debris from binding, the threads in the head can be compromised ... with a not so good outcome. With 100,000 mile Platinum Plugs, carbon buildup on the last few threads exposed to the combustion chamber are the culprit ... but with the above "touch" ... not an issue.