Need to plug coolant return located between first 2 runner on intake manifold

[MarkIII4Me]

I should have done this a long time ago. Problem is, I never noticed this coolant return until I was looking at some pictures here on the forums.

I realize that the easiest thing to do would have been to just run a line from the coolant pipe that wraps around the back of the block to the return in the head; but unfortunately I already plugged that portion of the line. Permanently.

The lower portion of the intake manifold is already installed. So what's the easiest way to plug it? I don't want it to leak. Can I get by with something like a hex plug? Is the thread npt? If so, what's the pitch?

 

[grimreaper]

looks like a 1/8npt, mine has a brass plug in it like the ones you find at homedepot, courtesy of the PO

 

[Halsupramk3]

if your talking about the coolant coming out of the head and to the tube on the lower intake i tapped the hole in the head and put a 1/8 npt hex plug in there flush as mentioned above. the line on the rear i put a piece of collant hose with a bolt on one end. I used screw clamps on the short piece of hose and put super black silicone on the bolt threads before insertion into the coolant hose.

no leaks.

 

[Poodles]

...or just loop it and let the coolant flow through the head as intended.

 

[MarkIII4Me]

Looping isn't really an option right now. However, if I plug the return at the lower intake manifold, will it leak where the manifold and the head meet? In other words, does it need to be plugged on the head itself?

 

[Van]

I capped the stock fitting with a ribber cap, installed it with a hose clamp, and applied thread sealant, then torqued it down. No leaks after doing a pressure test and running it for the past two days. Van

I should have done this a long time ago. Problem is, I never noticed this coolant return until I was looking at some pictures here on the forums.

I realize that the easiest thing to do would have been to just run a line from the coolant pipe that wraps around the back of the block to the return in the head; but unfortunately I already plugged that portion of the line. Permanently.

The lower portion of the intake manifold is already installed. So what's the easiest way to plug it? I don't want it to leak. Can I get by with something like a hex plug? Is the thread npt? If so, what's the pitch?

 

[CyFi6]

Looping isn't really an option right now. However, if I plug the return at the lower intake manifold, will it leak where the manifold and the head meet? In other words, does it need to be plugged on the head itself?

No it wont leak, the intake manifold gasket has a sealant around the hole for the coolant so you can put a plug in the manifold itself

 

[MarkIII4Me]

Sounds good. A npt hex plug and some liquid teflon it is.

Thanks guys