Well i was changing out the plugs on the rx7 i just bought because they were toast. The trailing plug on the front housing came out really hard and it turns out it stripped part of the threads. I think i just need to chase the threads and it should be fine since the latter part of the thread are still clean.

My question is what is the threading of the spark plugs i read some where it was 14mmx1.25 but i just want to double check

 

found the tap today. For future reference it is in fact 14mmx1.25pitch. Going to keep my fingers crossed and hope this works i would hate to have to pull or replace the engine because of a stupid spark plug after owning the car for only a week

 

Thanks for the confirmation on the thread pitch. Metal shavings are scary as hell.....take your time and you should be ok.

john ny

 

To add to your confirmation here are the five different plug thread sizes

M8 x 1.00

M10 x 1.00

M12 x 1.25

M14 x 1.25

M18 x 1.5

 

Well just got back from test driving the car. Everything worked out. I used some assembly lube on the tap, then wiped it out with a rag and lastly turned the engine over without the plug in there and seems to have gotten all the shavings out. Luckily just the threads at the beginning were stripped so it is still solidly threaded into the housing.

I will have to take pics of the plug i pulled out of the engine...looks like it has the original 129k on it the car has the electrode is like a point.

 

Yeah i would definately like to see that plug. Glad everything worked out for you man.


John NY

 

Just to bump this thread since I needed the spark plug threading myself...

Dont use a tap, use a thread restorer/chaser. Dip it in a very heavy weight grease. This will catch most the shavings and then crank it over to blow them out.

 

http://www.nationaltoolwarehouse.com...qx/product.htm

this is what i used and it worked good.