Modern Buddy

Hi,
I'm trying to replace the spark plug on my 2012 4T stella for the first time and I'm having issues. I disconnected the HT Lead cable, but I can't get the Box Spanner through the hole to get to the spark plug so I can unscrew it. The plastic hole is too small. I have a feeling I'm doing something stupid. Any suggestions are appreciated.

Once you remove the black plastic cover you'll have a much easier go of things. The cover holds the little rubber insert that is in your way.

So weird there is no mention of having to remove the plastic cover in the manual to take out the spark plug. Even the videos I've watched they don't remove anything. I know as soon as I get the cover off I'm not going to be able to get it back on haha.

Before I take off the cover I want to make sure I'm doing it right. Do I unscrew all these screws just to get the cover off?

First.. try to remove the round rubber boot around the plug opening.
I believe that they pop right out of there with a bit of wiggling. Or get it wet somewhat.
Good luck..

Oppps.. sorry, i was thinking of a 2t plug hole.. sorry.
Maybe if you just loosen all thise screws and make the shroud loosey goosey, you may be able to wiggle that wrench in the hole

Is it a bad idea to just make the hole bigger with a knife? Why would the manual not say anything about this

Yes you do need to take the fan shroud (side cover) off. Its just the 2 screws and 4 8mm bolts. Comes off easy and goes back on easy. The chrome cover on the bottom right will also come off, when you put it back together put the shroud on before the chrome cover. My 2013 4T has the bigger space for the spark plug with the rubber boot thats mentioned in some of the posts.

I've got the same year and model and didn't need to remove the fan shroud. Did you try the other side of the box spanner? Mine has one side that fits in that hole perfectly and one that doesn't.

That cover should just pop out. No need to remove the engine cover.

djp4059 wrote:Yes you do need to take the fan shroud (side cover) off. Its just the 2 screws and 4 8mm bolts. Comes off easy and goes back on easy. The chrome cover on the bottom right will also come off, when you put it back together put the shroud on before the chrome cover. My 2013 4T has the bigger space for the spark plug with the rubber boot thats mentioned in some of the posts.

Thanks for the info djp4059! I'm going to give it a try today.

Ok I took off the plastic fan cover and now I'm more confused than I was before.

After getting the cover off I tried to use the tool that came with the Stella 4T, but it was way too big for the spark plug. I found a ratchet that fit so I took out the spark plug. Once I got the spark plug out I put it next to the NGK-B7ES I bought as a replacement and realized they were completely different sizes. As you can see from the photo, the sparkplug in my bike was a NGK-CR9EH9 which is way smaller.

So this means that when I bought the bike new it didn't have the right engine in it or someone switched it out when I took it in for servicing. I have taken it to 2 different places over the years. Is this possible or do some Stella 2012 4T's come with a different sized spark plug?

According to the manual the following is the direct replacement:

Champion - RG4HC; MICO BOSCH - UHR3CC

According to sparkplugcrossreference.com:

http://www.sparkplug-crossreference.com ... P_PN/RG4HC

Details about Champion RG4HC:
Thread diameter: 10mm
Thread reach: 19mm
Seat type: flat
Hex size: 16mm
Tip configuration: non projected
Construction: Standard construction
Terminal type: Solid

Run search on link for compatible brands.

The 2T runs this:

NGK - B6ES:
Thread diameter: 14mm
Thread reach: 19mm
Seat type: flat
Hex size: 21mm
Tip configuration: non projected
Construction: Standard construction
Terminal type: Removable

I think you got the wrong plug.

Thanks Johnny O. I bought the NGK-B7ES because that is what scooterworks said was compatible with the Stella on their website. Must be a different model than mine. I appreciate your help:)

smillerlou wrote:Thanks Johnny O. I bought the NGK-B7ES because that is what scooterworks said was compatible with the Stella on their website. Must be a different model than mine. I appreciate your help:)

yeah I did:( I had visions of my mechanic swapping my entire motor and not telling me about it haha.

I was gonna say.. the plug on the left looks like a 2 t plug.
Did the smaller size of your stella spanner wrench fit that plug that you pulled out? If so, did then wrench go down the plug hole ok?
That was original issue.
Inquires minds want to know

jimmbomb wrote:I was gonna say.. the plug on the left looks like a 2 t plug.
Did the smaller size of your stella spanner wrench fit that plug that you pulled out? If so, did then wrench go down the plug hole ok?
That was original issue.
Inquires minds want to know

jimmbomb - The smaller side of the spanner wrench did fit in the hole, but it was too small to go around the spark plug. I was able to get the black shielding off and then I used a socket wrench to get the spark plug out. I can't remember if the spanner wrench came with my 4T or if I bought it after. Maybe that's for a 2T as well.

I did replace the spark plug with the correct one: Champion - RG4HC
but unfortunately that didn't do anything. I'm not sure what to check next so I think I have to get it towed to the mechanic.

jimmbomb wrote:I was gonna say.. the plug on the left looks like a 2 t plug.
Did the smaller size of your stella spanner wrench fit that plug that you pulled out? If so, did then wrench go down the plug hole ok?
That was original issue.
Inquires minds want to know

My guess, I think a 2T tool kit got put into your 4T along the way.

Most likely an honest mistake. I'd get a new wrench though so you don't get stranded with the wrong one in the future.

There is plenty of info here on troubleshooting your not starting issue. Do some reading and searching and you'll figure it out. Plus its free!