To drill or not to drill.....?

[Jambo1]

You all may have been following the "Engine Temp Gauges" post. Im trying to get a opinion to this senario.......

I want to take out my existing electrical tempature sending unit, drill it out and tap it to a larger size, (1/2" or 3/4") and stick in a aftermarket gauge. Reason being, the aftermarket gauge is a mechanical one, not electrical gauge and the sending unit on it is bigger that the stock electrical sending unit.

Any opinions are appreciated.

Thanks

[gsmikie]

get another thermostst housing with the fittings you need or put a t fitting in the manifold at the heater hose

[Highsteel]

I installed a cheapie aftermarket temp gauge from auto zone it came with all kinds of fittings so there was no need to drill. If the kit doesn't have the right fittings my suggestion is to go to a hardware store and get em. Drilling your intake seems like a big can of worms.

[Highsteel]

OOps I just remembered I'm not running a stock intake! I still would find some other way to run a mechanical temp gauge. tongue.gif

[badaboom]

JAMBO1
DRILLING/TAPPING IS NOT REALLY A GOOD OPTION IN MY OPTION

gsmikie
The fitting at the heater hose my be an option.
Although I still need to be able to utilize the heater.

[Crazy_Jeepman]

LOL Holes get there somehow. I have drilled early SBC heads for ACCY brackets and drilled holes bigger in Heads to increase bolt size. None of this stuff is hard to do, drill slow drill with a cutting fluid and I would lay a Magnet by the hole to be so as to catch the metal shaveings. Drilling on the motor would be my biggest concern shaveings in the coolant but then ever see what is in an old seasoned block, I doubt a few metal particals would hurt anything. If you do not feel comfortable don't do it. If you do be sure you use the right drill bit size for the tap to be used. if you want a 1/2" threaded hole you would not use a 1/2" drill bit ;)

[Lugnut]

And, don't forget that you're tapping a hole for natural pipe thread, not straight threads. If you tap for straight threads the sending unit will not tighten and then you WILL have opened a can of worms.
Personally, I'd avoid drilling a hole.

[Jambo1]

I came home thinking I was going to drill........and I bagged it. I chickened out. Seemed like everything could go wrong. I went to Ace Hardware and got some brass fittings that took me from 3/4" down to 1/2". The sending unit is so long that I had to make up three reducing fittings together to make it work. It's too thick to fit in the existing hole. It looks stupid.......but it works. And believe me, even though the sender is not in the block, it gets the coolent flow. I pulled the fittings off after running the motor for a few minutes. Bad mistake!!! Coolant everywhere. Luckily it wasnt that hot yet. Thanks for all the help, maybe if I ever replace my intake, I'll do it the right way. Came home from ace and my rear window stuck have way down and it's pouring here. :mad:

[badaboom]

Jambo1
So you got some fitting and used the original electrical sending unit location?

I am looking into making something off the heater water gallery on the left rear.
Probably get some fittings and see what is possible.

Still looking for best resolution.

I am glad you got your gauge working.

I will try and let you know what I finally do.

[Millerluck]

There is a very large pipe thread in the manifold that the heater hose goes to at the back.

You should be able to do some pluming back there with a "T" and end up with a place for the sender.

Are you using all the CTO's for the timming?
If not that would also make a great spot to put the sender.

Later

Larry Miller

[OBX-AUTOMOTIVE]

I THINK 3/4 IS A LITTLE SMALL......I WOULD GO TO 1"THEN PUT IN A Y..... AND A HAND VALVE...THEN YOU COULD PLUM IN A NICE HOT... SHOWER!!! :cool: :cool: :rolleyes: smile.gif

[OBX-AUTOMOTIVE]

SIMPLE..I LIKE SIMPLE,MECHANICAL GAUGES ARE SIMPLE,AND I TRUST THEM!! I SAY THE LESS ELECTRIC CRAP THE BETTER...DO THEY MAKE AN MECHANICL AMP GAUGE OR VOLT?????...OH!!! I WAS JUST KIDDING WITH YOU ON THAT OTHER POST!! smile.gif smile.gif

[Tad]

I can't believe there is no plug you can just pull on the block that goes into the cooling jacket like a SBC, guess I better look at my Buick 350 and see where I'm putting this gauge. That's going to byte if there is not one there.

[OBX-AUTOMOTIVE]

PUT LYLE ON THE LINE...SAY LYLE!!!! JUST LOOK AND YOU WILL FIND A PLUG OR A PLACE FOR YOUR GAUGE...I'M 99 AND 100% SURE!!!...OK BACK TO TAD!!! LYLE WILL NOT TALK BACK TO YA!!! HE'S A QUIT KIND OF GUY :cool: :cool: .......I THINK I'VE LOST IT!! PASS THE PILLS!!!..OH MY BACK!!!! :rolleyes: :rolleyes: :D

[Johnboy]

I have the mechanical sender on mine, just popped out the factory, used a nipple and bell reducer, another nipple for the sending unit to ride in, and put whatever coupling I needed on top. The only problem it sticks six inches out of the hood!
J/K...I would not try to drill and tap a cast manifold, Just MHO!
J

[Highsteel]

Millerluck's idea sounds like the safest and easiest to me...Course with GARY and I both living in the hills the shower idea may come in handy... ;) Maybe I'll go into business..Sneaky Pete's Mobile Showers of the Smokies...kinda catchy.. :D

[ June 29, 2002, 01:23 PM: Message edited by: Highsteel ]