Go Back   The Ford Barn > General Discussion > Early V8 (1932-53)

Sponsored Links (Register now to hide all advertisements)

Reply
 
Thread Tools Display Modes
Old 03-05-2016, 01:20 PM   #1
Al NJ
Member
 
Join Date: May 2010
Location: New Jersey, The Garden State
Posts: 98
Default Broken temp sender unit

I have a broken temperature sending unit in a '39 cylinder head.
It's broken below the surface, nothing to put a wrench on.
Should I just drill it out with progressively larger bits until I can just peel out the remains?
I did a search but couldn't find anything. Any help would be appreciated.
Thanks.
Al NJ is offline   Reply With Quote
Old 03-05-2016, 01:28 PM   #2
39topless
Senior Member
 
Join Date: Sep 2013
Posts: 1,027
Default Re: Broken temp sender unit

Drilling will leave metal fragments in the engine. I would probably remove the head to do it.
39topless is offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 03-05-2016, 02:22 PM   #3
deuce lover
Senior Member
 
deuce lover's Avatar
 
Join Date: May 2010
Location: Southern France
Posts: 3,784
Default Re: Broken temp sender unit

Is it broken off flush with the brass adapter fitting at the head and is the bulb portion part of it?
deuce lover is offline   Reply With Quote
Old 03-05-2016, 02:49 PM   #4
Al NJ
Member
 
Join Date: May 2010
Location: New Jersey, The Garden State
Posts: 98
Default Re: Broken temp sender unit

Sorry, I should have been more clear. The head is off the engine.
The bulb part is still in the head, but whats left of the bulb is about 3/8" below the surface.
I would imagine there aren't a lot of threads left engaging the head. ???
Al NJ is offline   Reply With Quote
Old 03-05-2016, 03:04 PM   #5
flatheadmurre
Senior Member
 
flatheadmurre's Avatar
 
Join Date: Apr 2015
Location: Sweden
Posts: 3,045
Default Re: Broken temp sender unit

There are extractors for broken pipethreads that should be able to fit the job.
If you got a plumber in the neighbourhood you can borrow one from.
Otherwise just drilling/grinding and taking out the threads should work...
flatheadmurre is offline   Reply With Quote
Old 03-05-2016, 03:29 PM   #6
4dFord/SC
Senior Member
 
4dFord/SC's Avatar
 
Join Date: May 2010
Location: Columbia, SC
Posts: 1,573
Default Re: Broken temp sender unit

Sponsored Links (Register now to hide all advertisements)
Quote:
Originally Posted by flatheadmurre View Post
There are extractors for broken pipethreads that should be able to fit the job.
aka internal pipe wrench.
4dFord/SC is offline   Reply With Quote
Old 03-05-2016, 03:50 PM   #7
deuce lover
Senior Member
 
deuce lover's Avatar
 
Join Date: May 2010
Location: Southern France
Posts: 3,784
Default Re: Broken temp sender unit

Quote:
Originally Posted by Al NJ View Post
Sorry, I should have been more clear. The head is off the engine.
The bulb part is still in the head, but whats left of the bulb is about 3/8" below the surface.
I would imagine there aren't a lot of threads left engaging the head. ???
Al.Here is a pic of what that assy should look like when installed.In this case the line for the bulb has been cut.So yours is broken off just below the hex?
Attached Images
File Type: jpg 37-39 Temp adapter 1a.jpg (108.4 KB, 7 views)
deuce lover is offline   Reply With Quote
Old 03-05-2016, 04:22 PM   #8
Al NJ
Member
 
Join Date: May 2010
Location: New Jersey, The Garden State
Posts: 98
Default Re: Broken temp sender unit

Thanks for the picture! Mine's broken off about 3/8" down in the head. In other words I can see about 3/8" of the female threads in the head. Looking at the picture I would guess there's only a couple of threads left on the sending unit that are engaged in the head, if it's the same type of sending unit.
I shot it with a little PB Blaster. I'll probably start drilling after dinner.
Al NJ is offline   Reply With Quote
Old 03-05-2016, 04:28 PM   #9
Karl Wolf
Senior Member
 
Karl Wolf's Avatar
 
Join Date: May 2010
Location: Mill Valley,Ca.
Posts: 1,423
Default Re: Broken temp sender unit

Quote:
Originally Posted by Al NJ View Post
Sorry, I should have been more clear. The head is off the engine.
The bulb part is still in the head, but whats left of the bulb is about 3/8" below the surface.
I would imagine there aren't a lot of threads left engaging the head. ???
What I would do-
Take a hacksaw blade and cut through the side of the brass until you see signs of the 3/8" pipe threads- DON'T cut into the cast iron. Move over 1/8" or so and do it again. The piece in the center of your two cuts (1/8" wide) can be peeled out toward the center of the hole with a punch sharpened on an angle. The remnant can be unscrewed.
(You may have to grind off the back of hacksaw blade to fit into the fitting)

Karl
Karl Wolf is offline   Reply With Quote
Old 03-05-2016, 06:52 PM   #10
rotorwrench
Senior Member
 
rotorwrench's Avatar
 
Join Date: Jun 2010
Location: San Antonio, Texas
Posts: 12,781
Default Re: Broken temp sender unit

One good thing about tapered pipe threads is the taper. If the right size drill is selected, a person could drill it out and only affect the last few turns of thread in there. Drills in fractional and letter sizes (alphabetic) can get you some precision there. Or you can try easy outs first. clean the thread bore as good as you can before the attempt. Bead blast lightly if possible & clean that out as good as you can. Tapers wedge themselves in pretty well so drilling or peeling the shell might be the best solution.
rotorwrench is offline   Reply With Quote
Old 03-05-2016, 07:18 PM   #11
39topless
Senior Member
 
Join Date: Sep 2013
Posts: 1,027
Default Re: Broken temp sender unit

I don't have an original head here to look at but I'm wondering if you can get at this from the back (inside). Maybe you can get a better grip on what's left of the sender.
39topless is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Sponsored Links (Register now to hide all advertisements)


All times are GMT -5. The time now is 04:47 PM.