i bought the fitting recommended in the DIY FAQ, m10 x 1.5. i just took the plug out of the block, and tried to thread the new fitting in. it will start, then immediately get tight, like it's the wrong thread.

i didnt want to force it, and bugger up the threads in the block.

the block i'm using came out of an early nineties protege, could it possibly need a different fitting?

 

It's a good possibility. I think only the Miata 1.6 motors had that threaded oil feed.

 

1.6L and early 1.8L engines have a preexisting location for the oil supply. It is located on the driver side of the block near the dipstick port. The correct size fitting to match up to it is a M10 x 1.5. Based on previous issues locating a correct fitting, you'll want to source a M10 x 1.5

 

pfft if the fitting is a brass one, shove that bastard in there!! You wont hurt the block and it will rethread the fitting!!!

lol jk.



But if you really want to know, you can always take a pencil, dowel, or something woodish that is a little bigger in size, and screw it in there SLOWLY, and it will "thread" the wood so you can find a size fitting to match. If you dont want wood, you can always take clay, and wrap it around a pen, then you coat the threads with oil and use the same process with the wood. But let the clay harden tho.

This is how I find fittings when I get boggled.

 

just looking at the plug that came out of the block, it looks right....

 

did you clean it out of all the crud that cakes in there?