C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
Sponsored by:
Sponsored by:

Oil Pressure Gauge Fitting '68 to '73

Thread Tools
 
Search this Thread
 
Old 10-15-2017, 04:07 PM
  #1  
buns
Safety Car
Thread Starter
 
buns's Avatar
 
Member Since: Feb 2006
Posts: 4,142
Received 690 Likes on 537 Posts

Default Oil Pressure Gauge Fitting '68 to '73

Anyone know the diameter and pitch of these threads?



buns is offline  
Old 11-07-2017, 11:26 PM
  #2  
buns
Safety Car
Thread Starter
 
buns's Avatar
 
Member Since: Feb 2006
Posts: 4,142
Received 690 Likes on 537 Posts

Default

Well, it cost me $15.00 to find out....

For future reference, they are both 5/16"-24.

Another question....Does this fitting have to a right angle in C3 Corvettes?
buns is offline  
Old 11-08-2017, 07:40 AM
  #3  
Cavu2u
Melting Slicks
 
Cavu2u's Avatar
 
Member Since: Oct 2013
Location: San Diego California
Posts: 2,561
Received 125 Likes on 105 Posts
Default

Originally Posted by buns
Well, it cost me $15.00 to find out....

For future reference, they are both 5/16"-24.

Another question....Does this fitting have to a right angle in C3 Corvettes?


We weren't ignoring ya. Just no one who had one apart saw your thread. It's tough to get to, and the old axiom If it ain't leakin', don't touch it was also working against you.
It should be a 90 degree fitting because the Gauge Panel butts up very close to the Firewall. It therefore eliminates a sharp bent of the nylon Oil Line.

Steve
Cavu2u is offline  
Old 11-08-2017, 09:10 PM
  #4  
buns
Safety Car
Thread Starter
 
buns's Avatar
 
Member Since: Feb 2006
Posts: 4,142
Received 690 Likes on 537 Posts

Default

Thanks for the info. I bought the fitting to experiment with, hoping there was something available to adapt it to a -3 AN fitting which could be used with a braided stainless oil line. It's the same diameter as 1/16th pipe thread, but the pitch is wrong.

I was bored and it was cold out, so I whittled one off in my lathe. Took many hours, so this will be the first and last.



buns is offline  
Old 11-08-2017, 10:13 PM
  #5  
69ttop502
Le Mans Master
 
69ttop502's Avatar
 
Member Since: Mar 2001
Location: Watkinsville, GA and Glen Cove, NY
Posts: 5,790
Received 855 Likes on 626 Posts

Default

The braided line I am using is 4an. I found an adapter on Amazon that works but it wasn’t easy to find. Will look for it if you are interested. Not aware of a braided oil gauge line that is 3an.
69ttop502 is offline  
Old 11-08-2017, 11:17 PM
  #6  
buns
Safety Car
Thread Starter
 
buns's Avatar
 
Member Since: Feb 2006
Posts: 4,142
Received 690 Likes on 537 Posts

Default

Hmmmm...I had no trouble finding -3 AN line. They are usually described as brake line, but will work with oil pressure gauges as well.

https://www.speedwaymotors.com/Braid...sku=91031845-3


https://www.summitracing.com/int/par...0308/overview/
buns is offline  
Old 11-09-2017, 06:58 AM
  #7  
69ttop502
Le Mans Master
 
69ttop502's Avatar
 
Member Since: Mar 2001
Location: Watkinsville, GA and Glen Cove, NY
Posts: 5,790
Received 855 Likes on 626 Posts

Default

Gotcha, I am using the Autometer line and it is -4 as was the Allstar at Summit but I was searching for the oil gauge line. Didn’t know the brake line stuff would work.����
69ttop502 is offline  
Old 11-10-2017, 02:35 PM
  #8  
TimAT
Le Mans Master
 
TimAT's Avatar
 
Member Since: Oct 2006
Location: Gladstone MO
Posts: 7,121
Received 424 Likes on 385 Posts
C3 of Year Finalist (appearance mods) 2019

Default

I just replaced my 40+ year old nylon line with -4 braided line. The fittings in the block and the gauge are 1/8NPT. I used 1/8 NPT to -4 90* fittings.
TimAT is offline  
The following users liked this post:
Primoz (09-29-2021)
Old 11-10-2017, 02:46 PM
  #9  
pws69
Melting Slicks
 
pws69's Avatar
 
Member Since: Nov 2001
Location: Eastern US XX
Posts: 2,668
Received 40 Likes on 30 Posts

Default

Originally Posted by TimAT
I just replaced my 40+ year old nylon line with -4 braided line. The fittings in the block and the gauge are 1/8NPT. I used 1/8 NPT to -4 90* fittings.
This is correct - they are NOT "both 5/16"-24" although they are close!
pws69 is offline  
Old 11-10-2017, 03:01 PM
  #10  
69ttop502
Le Mans Master
 
69ttop502's Avatar
 
Member Since: Mar 2001
Location: Watkinsville, GA and Glen Cove, NY
Posts: 5,790
Received 855 Likes on 626 Posts

Default

My 69 gauge was definitely not 1/8 NPT but 5/16-24. None of the adapters in the Autometer kit fit. Hard to find the 5/16-24 to -4 adapter but I did find one. I will post a pic as my gauges are out of the car.

Last edited by 69ttop502; 11-10-2017 at 03:02 PM.
69ttop502 is offline  
The following users liked this post:
carriljc (12-07-2018)
Old 11-10-2017, 04:31 PM
  #11  
theandies
Team Owner

 
theandies's Avatar
 
Member Since: Jun 2001
Location: Virginia USA
Posts: 22,661
Received 756 Likes on 525 Posts

Default

This is the kit I used:



Summit PN SUM-G2960
theandies is offline  
Old 11-10-2017, 11:08 PM
  #12  
buns
Safety Car
Thread Starter
 
buns's Avatar
 
Member Since: Feb 2006
Posts: 4,142
Received 690 Likes on 537 Posts

Default

Everything I know about this fitting:


It is 5/16-24...it is not tapered.







This is a 5/16-24 bolt with 2 nuts on it. Below that is the fitting with the same nuts.







This is a 1/8" pipe fitting, compared to the gauge fitting. It is much larger.







This is the tube fitting on the 5/16-24 bolt. It fits on the gauge fitting.




buns is offline  
The following 2 users liked this post by buns:
carriljc (12-07-2018), Primoz (05-13-2021)
Old 11-11-2017, 07:02 AM
  #13  
69ttop502
Le Mans Master
 
69ttop502's Avatar
 
Member Since: Mar 2001
Location: Watkinsville, GA and Glen Cove, NY
Posts: 5,790
Received 855 Likes on 626 Posts

Default

That is the same fitting as on my 69 Buns, definitely was not 1/8 NPT.
69ttop502 is offline  
The following users liked this post:
carriljc (12-07-2018)
Old 11-11-2017, 11:46 AM
  #14  
Cavu2u
Melting Slicks
 
Cavu2u's Avatar
 
Member Since: Oct 2013
Location: San Diego California
Posts: 2,561
Received 125 Likes on 105 Posts
Default

Now THAT is clarification!

Steve
Cavu2u is offline  
Old 09-29-2021, 02:25 PM
  #15  
Primoz
Burning Brakes
 
Primoz's Avatar
 
Member Since: Jul 2012
Location: Slovenia, EU
Posts: 1,116
Received 263 Likes on 128 Posts
2017 C3 of Year Finalist

Default

Originally Posted by 69ttop502
My 69 gauge was definitely not 1/8 NPT but 5/16-24. None of the adapters in the Autometer kit fit. Hard to find the 5/16-24 to -4 adapter but I did find one. I will post a pic as my gauges are out of the car.
Can you share the information of where did you find the adapter?
Primoz is offline  
Old 10-01-2021, 12:19 PM
  #16  
vettebuyer6369
Administrator
 
vettebuyer6369's Avatar
 
Member Since: Jul 2000
Location: About 1100 miles from where I call home. Blue lives matter.
Posts: 51,422
Received 5,331 Likes on 2,775 Posts

Default

Originally Posted by Primoz
Can you share the information of where did you find the adapter?
That post is from 4 years ago.
vettebuyer6369 is offline  

Get notified of new replies

To Oil Pressure Gauge Fitting '68 to '73




Quick Reply: Oil Pressure Gauge Fitting '68 to '73



All times are GMT -4. The time now is 04:15 PM.