I'm attempting to tap my aftermarket aluminum intake manifold so the fitting for the heater hose will thread all the way into the manifold. The fitting for the heater hose as well as the temperature sending unit (in the top of the manifold) are suppose to be 1/2"-14 NPT as far as I know. Both threaded holes easily accept the heater hose fitting as well as the sending unit, however "in both cases" they will not thread all the way in, leaving too much thread area exposed to my liking.
So, I started today with the threaded hole for the heater hose fitting, and I'm tapping my way right along, little by little, but I don't think it looks right yet. It's difficult to tap this hole because I have to use a hand wrench, as the normal tapping T-handle will not maneuver this close to the aluminum manifold. The fitting in my pic is definitely further threaded in from where it was before I started tapping, so you can imagine how bad it looked.
I thought I'd stop and take a couple of pics for you all to see, and offer any advice you might have to make this easier. I suspect tapping the sending unit fitting will be easier to tap, but I haven't done it yet. I'm wondering if the manufacturer didn't use NPT threads but straight 1/2" threads?
You can see in the 2nd pic (if you zoom in) how much room is left from the end of the fitting to the inside face of the manifold....tapping it all the way in should make the fitting about flush with the face of the inside water channel.
Any thoughts appreciated,
John
So, I started today with the threaded hole for the heater hose fitting, and I'm tapping my way right along, little by little, but I don't think it looks right yet. It's difficult to tap this hole because I have to use a hand wrench, as the normal tapping T-handle will not maneuver this close to the aluminum manifold. The fitting in my pic is definitely further threaded in from where it was before I started tapping, so you can imagine how bad it looked.
I thought I'd stop and take a couple of pics for you all to see, and offer any advice you might have to make this easier. I suspect tapping the sending unit fitting will be easier to tap, but I haven't done it yet. I'm wondering if the manufacturer didn't use NPT threads but straight 1/2" threads?
You can see in the 2nd pic (if you zoom in) how much room is left from the end of the fitting to the inside face of the manifold....tapping it all the way in should make the fitting about flush with the face of the inside water channel.
Any thoughts appreciated,
John