Chasing threads and repairing the seats for new spark plugs.

[Dale Finch]

Well doing some work on one of my '55 Cubs, I noticed there was some blow by around the spark plugs...just some small bubbling. So I decided to clean the seat and install new spark plugs with new washers, hoping to seal the gases.

Unfortunately, there's still a little bit of leakage. Do any of you have any suggestions for fixing this? In doing a little bit of online research, I found this tool...
Do you think this would work? And what size do I need for the Farmall Cub?

Spark Plug Seat and Thread Cleaning Tool | Products | Gas Engine Controls

www.gasenginecontrols.com

 

[tst]

if you have a die grinder and straight wire brush on the end works just find, seal the plugs with never seize

 

[staninlowerAL]

A small drill motor with a cone shaped wire brush chucked in it will also work. A small square of plumbers emery cloth placed over the hole and turned by the drill motor/brush will add a little more abrasive polishing to the seat. I used this method on the AVERY V at LACubfest when we were there a couple years ago to polish the valve seats. JMHO Stan

 

[Jim Becker]

Agreeing with the previous responses including the never seize, I think it looks like a clever tool and probably works pretty well. To your third question, the Cub spark plugs are 18mm.

 

[Dale Finch]

I'm mostly concerned about the condition of the seat... It's rather pitted. When I return from a week-long+ road trip up to the Northeast, I will tackle this head-on and try these suggestions.
Thank you!

 

[dreece]

Sometimes an extra washer helps

 

[staninlowerAL]

I'm mostly concerned about the condition of the seat... It's rather pitted...................

Thinking out of the box so here's a suggestion to address the pitted metal. Cut a thin flat metal disc to the correct size from a can top, clean up the area with alcohol and use a thin layer of JBWeld as a filler. Screw a plug in place to position and hold it til it hardens. A little dab coating of oil or a thin plastic cover between the washer and the filler/head will allow you to remove it when it hardens because JBWeld won't stick to oil or plastic.. Stan

 

[Farmallsodbuster]

Thinking out of the box so here's a suggestion to address the pitted metal. Cut a thin metal disc to the correct size from a can top, clean up the area with alcohol and use a thin layer of JBWeld as a filler. Screw a plug in place to position and hold it til it hardens. A little dab coating of oil or a thin plastic cover between the washer and the filler/head will allow you to remove it when it hardens because JBWeld won't stick to oil or plastic.. Stan

That jb weld is great stuff! Just replaced some wheel seals in a Troybilt tiller for someone using it. A previous person had done it and gouged the shaft and the new seal leaked. I jb welded up the gouges and sanded it down smooth and replaced the seal again. Great stuff!

 

[dreece]

Thinking out of the box so here's a suggestion to address the pitted metal. Cut a thin metal disc to the correct size from a can top, clean up the area with alcohol and use a thin layer of JBWeld as a filler. Screw a plug in place to position and hold it til it hardens. A little dab coating of oil or a thin plastic cover between the washer and the filler/head will allow you to remove it when it hardens because JBWeld won't stick to oil or plastic.. Stan

The high temperature JB should work well