Spark Plug Question?

[dodgextreme4x4]

I rebuilt the top end of my 98 blaster. It runs great for about 30 mins then it starts to bogg down and backfire really bad. I took the spark plug out and its smashed down where there is no gap. What would cause this to be happing. Thanks

 

[brandoz28]

try a fresh plug and see if it does it again, otherwise pull the head and make sure nothing is in the cylinder and making contact with the plug

 

[samolia]

are you using a NGK B8es or BR8es like your suppose to??

 

[dodgextreme4x4]

This is the second time ive tried a new plug and did the same thing runs good for 30 mins then gets boggy and starts backfiring

 

[dodgextreme4x4]

The spark plug is a BR8es

 

[dodgextreme4x4]

Spark Plug Part No. Stock No. Plug Gap Photo
Standard B8ES 2411 .028

Why does ngk web site say to use the b8es plug but everyone recommends the br8es

 

[brandoz28]

you need to pull the head off and figure out why its smashing the spark plugs

 

[dodgextreme4x4]

how is it possible that the piston comes up far enough to hit the spark plug?

 

[brandoz28]

the ground strap would have to hang down far enough to make contact with the piston or something else in there