Does someone here know the size and pitch of this bolt?

I have tried every bolt I have that even looks close (a lot of them) but nothing fits.

There is a harness guide and a ground I would like to attach here, and the location makes it somewhat difficult to measure.


Looking for the size of bolt to use this hole

 

Talking about the coolant drain bolt? Seem to remember posting that a long time back, my search is revealing nought however - and wouldn't think that's a good earth point. The neighbouring hole, if that's what you mean, I think is just blind with no thread - open to correction there!

 

The hole to the right of the coolant drain plug is a leftover from the FC, there was a motor mount bolted to the side of the engine there.

The hole may not be tapped, it may just be an as-cast hole. It's going to be a relatively large bolt, either M10 or M12.

Also just above that is an M6 bolt hole (10mm head bolt) that normally has a clip or something attached to it. That may be a possibility or have a bracket bolt to that and come down to where you need it.

Dale

 

That hole is tapped, but it is rather difficult to measure the pitch in that location.

I will just try some taps and thread chasers and see if any of them fit.

 

It's probably going to be a fine pitch if my FC memory remembers right. I seem to remember if you lost the nuts that hold that engine bracket on you were SOL, none of the other bolts handy would work.

May want to post up in the FC section, one of those guys may know off the top of their head.

Dale

 

i wanna say the FC is 10 x 1.25 right there. Mazda generally follows the JIS standard, so 6 is a 1.0, 8 is 1.25, etc

i also think that Dale is right, the harness goes either further forward, or on the higher up hole

 

Definitely not 1.25. I put a 2.0 thread gauge in there and it was close to that. Just too hard to get a measurement with the motor in the car. Wish I had checked this before putting the motor in.

 

The hole is 12mm x 1.75mm

There was too much gunk in the threads to get a bolt in there. Probably paint from a recent rebuild.

A few minutes with a 12x1.75 Bottom Tap, followed by the same size thread chaser, and a 20mm long bolt goes right in.

One of the best tools I ever bought for tapping holes is this ratcheting tap wrench. It fits in surprisingly tight spaces.

The handles slide through the ratchet body, and well, it ratchets.