2001 400ex Spark Plug removal.

[PERTU]

Hi,

I'm trying to remove the spark plug from my 2001 400ex and I don't have the honda toolkit. I tried a 5/8" spark plug socket and 18mm spark plug socket, but they don't fit. What kind of socket should I use?

Thanks.

[JOEX]

Originally posted by PERTU
Hi,

I'm trying to remove the spark plug from my 2001 400ex and I don't have the honda toolkit. I tried a 5/8" spark plug socket and 18mm spark plug socket, but they don't fit. What kind of socket should I use?

Thanks.
It's an 18mm and you may need to grind down the sides of the socket or find a thin wall socket.

I have an old (20+ years) Craftsman socket set and it works just fine:)

[PERTU]

Thanks,

I'll try to find a thinner 18mm.

[RiderTRX400ex]

if you get the right 18 you can make it fit without any mod to the socket.. its kinda tricky

[gojk]

It is sad that this is the hardest thing to do on the 400ex. I ended up buying a cheap socket from Checker and grinding it down. Works good, but I am a little annoyed that I had to go that far to get the spark plug out.

[NacsMXer]

Originally posted by RiderTRX400ex
if you get the right 18 you can make it fit without any mod to the socket.. its kinda tricky

I agree. I have a Craftsman deep well 18mm, and some off-brand 18mm and they both fit with a little "wiggling" to get it down there. There's like two spots on the head that protrude ("10 and 2" positions in the hole) which make it a very tight fit.

[DAVE14]

get a cheap deep 18mm. grind it down nice & thin short extension even a stubby ratchet works well down that hole

[bwamos]

As a note if you go to Lowes or Home Depot, in the chainsaw/weedeater/lawnmower area they'll usually have those sheetmetal sparkplug wrenches in a few different sizes.

[JOEX]

Originally posted by bwamos
As a note if you go to Lowes or Home Depot, in the chainsaw/weedeater/lawnmower area they'll usually have those sheetmetal sparkplug wrenches in a few different sizes.
I've been meaning to check into those, seeing if one fits the 400ex. Aren't they the same style as what comes in the stock tool kit?


Originally posted by gojk
It is sad that this is the hardest thing to do on the 400ex. I ended up buying a cheap socket from Checker and grinding it down. Works good, but I am a little annoyed that I had to go that far to get the spark plug out.
I think it's quite simple but maybe i'm just lucky:p

Another thing i've wondered... Maybe some 400ex heads are cast slightly differently and have more material around the spark plug causing some people more difficulty than others...

[GPracer2500]

Originally posted by JOEX
.....Another thing i've wondered... Maybe some 400ex heads are cast slightly differently and have more material around the spark plug causing some people more difficulty than others...

I've often thought this is probably true. I know I've seen fins on different heads that were a little different.

[JOEX]

Originally posted by GPracer2500
I've often thought this is probably true. I know I've seen fins on different heads that were a little different.
Time to confirm this theory, everyone go measure your sockets!!!!:p

The Craftsman 18mm 3/8" drive deep well socket I use to remove the spark plug has an approximate outside diameter of .925".

[wilkin250r]

I got lucky. I bought a Stanley deep socket set from Wal-Mart for the sole purpose of grinding down the 18mm socket.

Turns out, I didn't need to grind it down, it fits just fine.

Measured at 0.937" and it barely fits. I can feel it making contact with both sides.