I need a spot to add a second temp sensor. Does anybody know if this boss in the pic goes into a water jacket. I'm sure it does I just like to be positive before I go and drill it out. I'd like to put my second sensor there if possible. Thanks Tim

 

Just looked on my intake manifold and it does not have the raised part of the casting, however there is a water channel below that area.
I would remove the manifold to drill it anyway as you dont want swarf clogging up the holes in the rear of your head gasket.

 

Some have the "boss" some don't. My 2000 does. Best I remember the newer 'Ls did not.

You do not have to remove the intake to drill into the boss. Just go slow and use a shop vac to get the chips. When you tap it use alot of grease on the tap to pickup shavings. When your done pick out whatever chips you may see.

Many of us have done this or had done with no ill affect.

 

Thank you gentlemen very much. I'll get it drilled out and tap this evening. It's a 99 so maybe just the ones with the older style manifold have this raised area.

 

'01+ do not have the boss but they do have a stamp on the intake where the boss used to be. I drilled and tapped mine on the stamping...grease on the drill bit and tap will keep anything out of the water passage.

 

I own a 2003 Lightning and want to drill my intake to put a temp sensor in it. My intake doesn't have the raised boss on it. Is the intake thick enough to drill and tap without the boss? I don't want to do this and tighten it and the intake cracks, that would be bad, very bad.:santa:

 

I just put a tee at the spot behind the drivers side motor mount... I have my electric fan sensor and my temp sensor there. Worked fine for 100k miles.

 

I thought about that. But everyone i spoke to said that the water not flowing over the sensor itself would not give an accurate temp reading. If its in a tee theres no way for the water to flow over it. Not saying your setup mis wrong just eveyone said it wouldn't work.

 

If we're talking about a water temp sensor, why not put it in the thermostat housing? I drilled and tapped mine for my gauge, and it works perfectly without any leaks. Very easy to do.

 

I thought about that also. What i'm trying to do is install an electric fan on my truck. But my Autometer temp gauge sensor is where i ned to put my electric fan sensor. I do know that the Autometer sensor is alot smaller than the fan sensor. Where exactly did you drill and tap the housing at? Thanks John.

 

You can drill and tap the intake...like I said, look on the intake for a stamp on the front passenger side exactly where the old ones had the boss. You can drill it and tap it and get 3-4 threads in it. I just wouldn't crank the sensor in too tight...

 

It's a hell of a lot easier to drill/tap the thermostat housing.

If you are standing in front of the truck, I drilled mine right on top of the housing, at about the 1 o'clock position. Just mark the spot with a permanent marker while the housing is still attached, pull it off, and drill/tap it for the threads on your sensor. Just to be safe, I put a little JB weld on the threads when I screwed it in. Been this way for over a year, and no issues.

 

So i should use JB Weld instead of teflon tape? I think it'll be easier to do the thermostat housing like you said. Just have to get the hole location right.