Topic: Frozen #2 spark plug - CB750K4!!!!

[andy750]

Hi all,
Beautiful day here in the Northeast and was ready to go for a ride but...#2 cylinder wasnt firing. I tried to remove #2 spark plug (the rest came out ok) but its stuck in their solid!!! Sprayed some PB blaster down there but nothing....warmed up engine on 3-cylinders but still it wouldnt budge...Im using a standard 18mm socket. These plutgs are really old and havent been replaced by me at all in the last 4000 miles (when I bought the bike)....other plugs look worn. So does anyone have any experience of successfully removing frozen spark plugs!?? Im desparate to go for a ride :-)

Thanks for any input,
Cheers
Andy in Boston

[jdpas29]

one trick that may work is to tap your ratchet handle back and forth with a hammer just enough to get a good hit... nothing crazy.

sometimes moving a stuck bolt, or in this case plug, takes turning it a little in the direction it's already gone... even if it seems like it's not moving at all. 

also... you can take a long, flathead screwdriver and put the tip on the metal part of the plug that has the nut on it.  tap the butt of the screwdriver with a hammer. 

let me know how it goes...

[volz1fsu]

What about getting a propane torch in there to warm up the plug and the surrounding area.  I don't think that the heat from the other three cylinders would work its way over to the one that is frozen, the aluminum wicks the heat away to good.  Try to spray some more lubricant on it when it is hot because the heated threads will draw it in better than cold ones.  Just be carefull not to take the threads out with the plug or you will have to take the head off to heli-coil new ones in.

[andy750]

Update -tried the hammer method suggested as well as more PB blaster but to no effect -it wont budge. Even got the Honda spark plug socket now with a 10` screwdriver for leverage but nothing. Dont have a propane torch to try this method but looks like Ill be taking it to my local bike shop next weekend to see if they can help :-(

Thanks in any case,
cheers
Andy in Boston

[mick750F]

   Andy...Do you have an impact driver? More soaking, heat and light use of an impact driver could do it. I'd keep at it for the week. You may be able to avoid a trip to the shop. I have a spare impact driver if you'd like to give it a try.

Mike

[MRieck]

Unfortunately it sounds like it is cross threaded in there. Not that hard to do on #2 or#3.

[andy750]

I have a feeling you are right Mike....if that is the case whats the best way to remove it?

Thanks
Andy

[Tim2005]

Hey Andy, how ya doing? Sounds a bit of a problem you've got there, if the thread is gone then you need to take the head off and get it helicoiled. However, first I'd try everything to get it hot, as that does make rusted-in ones much easier to get out, and the best way for that is to get that cylinder running - maybe you can get a little spark going from the remains of the plug that'll be enough. Try swapping the #2 & 3 ht leads over just in case there is a problem there, check there's fuel getting in too (pull the float bowl, make sure it's filled and then whip the jets out & clean them). You could even try pulling the airbox off and spraying some Easy Start (ether) into that carb while it's running on the other 3 - nothing to lose!

Also, you could try slightly lifting #2's cap away from the plug while it's running, so that a spark jumps from cap to plug- this has a knock-on effect for some reason and can increase the spark at a plug. Plus there's the added fun of an electric shock up your arm if your plug cap is dodgy.

Finally, I wonder, maybe someone else can advise, if leaving #3 plug cap off will actually increase the size of the spark that #2 is getting?

Basically, any way you can get that cylinder firing will get it hot, which will in turn make that plug easier to shift.

I hope it helps


Tim

[andy750]

Hi Tim,
Good to hear from you and I hope all is well with you...I was feeling pretty depressed today at the thought of not getting to ride but your suggestions have cheered me up so thanks for the input. Ill be putting them to the test as soon as I get back in the garage. I really dont want to pull the engine as my other K4 is requiring this to fix a leaky head gasket :-)...seems Ive been wrenching all winter and still no nearer to getting to ride..and I have 3 bikes!! Crazy!!
Thanks again,
Andy

[byidesign]

There is on crazy way ,that has worked for me in the past.
   Go down to your local electronics store,{radio shack} had the stuff I
    bought. It's CO2 in a can with a spray nozzle, made for testing electrical
      boards.
         If the bike runs, get it warm, then point the nozzle at the insulator,and hex
    part of the plug,and give 2-3 second bursts, @ 10seconds apart, for about 6 tries.
       then put a "Good" 6 point socket and wrench , and back it out.
       it may take a couple tries to do it.
           It's worked for me...........
                 Hope it helps

[Kelvin8]

slip a 3 or 4 foot length of pipe over your wrench handle, the additional leverage should do the trick. I once had to remove a recalcitrant bolt from a starter motor and used the pool skimmer handle (about 6 feet long) and that worked like a charm.