Flathead - valve hits sparkplug tip

[guy1unico]

On 2 of my cylinders the valve is crushing down the spark plug tip. I put another spark plug washer on those 2 plugs which seems to solve the problem for now. What do you think is causing this? I think this just started to happen in the last 6 months.
Thank you,
Guy

 

[GreenMonster48]

What kind of plugs do you have, and what do you have for heads (stock, Edelbrock, stock milled, etc)?

Have you re-torqued your heads? Maybe the gaskets are settling. Probably better to ask this question on the early V8 forum.

 

[darrell]

wrong plugs high lift cam

 

[Motorhead6]

You may have essentially "clocked" your troublesome plugs. That is by adding washers under the seat, the electrodes are in a different position radially and out of the reach of the valves or you may have raised them to out of reach of the valves. This is an acceptable work-around to changing the cam or whatever other fix is in order. If, however, there are signs of gas leakage, damage to the seat on the head will ensue and you need to address that problem. You can use copper washers of the same thickness as the double seals that fixed the radial issue. If the fix is due to raising the plugs, go a little further with thicker washers and add the same to all of the plugs just for peace of mind on the other plugs.

 

[Alaska Jim]

If this is a new condition to an eng that has been running with no problems until now it is possible that there is a carbon build -up this can sometimes be cured with a "top end" cleaner. atf, mmo, etc.