New 2-stroke engine won't start

[DieselTech]

Heres another pic showing the same length reach plug, but the electrode is longer. I believe this is due to it being a different heat range plug. I wish I could find what a autolite 4123 crosses to in ngk.

 

[DAMIEN1307]

I wish I could find what a autolite 4123 crosses to in ngk.

• AUTOLITE SPARK PLUG 4123 (CHAMPION L82YC / NGK BPR6HS)

 

[DieselTech]

• AUTOLITE SPARK PLUG 4123 (CHAMPION L82YC / NGK BPR6HS)

I'll have to do some investigating now, I figured that autolite 4123 was a hotter plug, but appears to be the same heat range. But its a way different construction.

 

[DAMIEN1307]

I figured that autolite 4123 was a hotter plug, but appears to be the same heat range

If your looking for a hotter plug in the NGK line of plugs, just substitute the number "6" in the plug letters and numbers for a "5" or a "4"...5 is hotter than 6...4 is hotter than 5 etc...DAMIEN

 

[DieselTech]

I will say 1 thing I've noticed between the autolite 4123 & the ngk br6hix. When running the autolite 4123 the ceramic & electrode are a reddish to brown color. If I switch to the ngk br6hix the ceramic & electrode stay black & oily, like it's too cold of plug.

 

[DAMIEN1307]

If I switch to the ngk br6hix the ceramic & electrode stay black & oily, like it's too cold of plug.

I have not known too many people here in the forums that even waste their money on iridium plugs for these motors...better off with the coppers...DAMIEN

 

[DieselTech]

I have not known too many people here in the forums that even waste their money on iridium plugs for these motors...better off with the coppers...DAMIEN

I'm a gearhead & wanted to try a iridium plug, I havent made my conclusion yet, but I think the iridium plugs dont foul as easy. I really havent got to run it long enough to make a good or bad opinion on them yet.

 

[Karl Snarl]

I don't think I took that much off, I only gave it a light sanding.

This happened after tried out a B6HS spark plug. Looks like the threads are slightly longer than the stock plug that came with the kit.

I use bp on some and never have them hit. Only time I ever hit was when I had a 38mm jug and a 40mm throw on the crank. I was in a hurry, didn't measure or check and just went to it. Bent the gudgeon pin and broke the bearing and had a nice dent in the middle of the piston. Not to mention the new plug was toast.

 

[Wrench]

. Looks like the threads are slightly longer than the stock plug

This is just a reminder to prevent stripping out the S/P threads in the head

Any threads sticking out in the combustion chamber will get carbon on them.
Carbon on a thread will make the S/P stubborn to unscrew and it will have to be forced a little
When the S/P is removed the carbon on the thread will strip or starts to strip the S/P hole.

This happens alot to new M/B builders So use an indexing S/P washer to raise the S/P up a little so not threads are sticking out

 

[HumanPerson]

Wrench
Merry Christmas and Happy Holidays my Brother!