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Oil Pressure Gage Fitting Dilema

Posted: Tue Jun 14, 2016 1:29 pm
by Riviera Wish
I have an original CC oil pressure gage copper tube that connects the pressure gage to the engine. The tube incorporates female compression fittings on each end as shown in the attached photo. The fitting shown connects to the oil pressure gage but the connection at the engine is the problem. I need to get from a 1/8" NPT male pipe thread at the engine to the copper 1/4" pressure line to the oil pressure gage shown in the photo. Does anyone know a source for a male compression fitting that will mate to the original CC oil pressure gage fitting?
I could splice a modern fitting into the oil pressure line to make the connection to the engine but would like to keep the line original if possible.
Suggestions would be appreciated.

Re: Oil Pressure Gage Fitting Dilema

Posted: Tue Jun 14, 2016 5:42 pm
by jim g
If your still running the oil cooler then you will need the original fitting. I suggest Van Ness or Jim Staib either one should have one.

Re: Oil Pressure Gage Fitting Dilema

Posted: Tue Jun 14, 2016 6:20 pm
by George Emmanuel
I see two different fittings in the picture. I see a 1/4" compression ferrule and an elongated 1/4" flare nut. Are these correct?

George

Re: Oil Pressure Gage Fitting Dilema

Posted: Tue Jun 14, 2016 7:25 pm
by mbigpops
That is a ferrule and a long compression nut.

Re: Oil Pressure Gage Fitting Dilema

Posted: Wed Jun 15, 2016 6:16 am
by George Emmanuel
Wow, I"ve never seen a compression nut like that. Is it a special nut designed for certain installations to counteract vibration?

George

Re: Oil Pressure Gage Fitting Dilema

Posted: Wed Jun 15, 2016 3:31 pm
by charlesquimby
Looks like a nut used on oil or gas furnace connections... CQ

Re: Oil Pressure Gage Fitting Dilema

Posted: Wed Jun 15, 2016 5:33 pm
by mbigpops
Per McMaster Carr "Long nuts have extra surface area contacting the tubing for high-vibration applications.
"

Re: Oil Pressure Gage Fitting Dilema

Posted: Fri Jun 17, 2016 8:17 am
by jfrprops
are you guys sure about that "long compression nut" ??? I have never encountered such. Looks like a normal flare nut to me?

to me it looks like two incompatible pieces as suggested. ??

John in Va.

Re: Oil Pressure Gage Fitting Dilema

Posted: Fri Jun 17, 2016 11:05 am
by Riviera Wish
This is the original compression fitting used by CC on the back of the oil pressure gages (at least on Rivieras). As it turns out, thanks to Jim Staib's guidance, this is identical to the thread used on some current day 1/4" compression fittings. The long nut shown in the original photo is definitely an original CC compression fitting for the oil pressure gage line.
Thanks for the discussion.
Steve

Re: Oil Pressure Gage Fitting Dilema

Posted: Mon Jun 20, 2016 1:41 pm
by jfrprops
Steve,

Just to follow up and learn something:

I don't question that the nut in the picture is original...and surely of that time period....I just question the ferrule.....I would think this is a flare connection.....???? Now is would think that being an oil pressure line....it was not a critical as say a gas line...but I have never seen that nut and collar used in tandem???

John in Va.

Re: Oil Pressure Gage Fitting Dilema

Posted: Mon Jun 20, 2016 8:57 pm
by mbigpops
Steve,

I just re-did my oil pressure line with new long nuts and ferrules and today it leaked on both ends.

I called Jim G and he explained to me that the threads may be slightly different on the newer long nuts which makes it difficult to compress the ferrule.

Fortunately I had kept the originals like you have so I swapped the originals in.

Hopefully that solves the problem.

Mark

Re: Oil Pressure Gage Fitting Dilema

Posted: Tue Jun 21, 2016 11:43 am
by Riviera Wish
John in VA.
I purchased this '52 Riviera in a disassembled state. However, I believe the oil pressure gage line with the ferrule and compression nut in the photo is 'original'. The connection on the back of the oil pressure gage is a compression fitting not a flare fitting. This is my first CC restoration so I am far from being an expert but the conclusion that the nut in the photo is a compression fitting and not a flare fitting seems right. Come to think of it, what would the difference be of a flare nut versus a compression nut in this application; seems like either one would 'compress' the ferrule????
One thing I do know is that I am at the low end of the 'brass fitting learning curve'.
Steve

Re: Oil Pressure Gage Fitting Dilema

Posted: Tue Jun 21, 2016 1:46 pm
by jim g
Flare nut uses a flare on the tubing to seal. Compression fitting uses a ferrule to compress around the tubing to seal it.

The compression fittings that Chris Craft used up through the late 50's were surplus WW2 aviation fittings. Which is why the threading is close but not exactly whats available today.

Re: Oil Pressure Gage Fitting Dilema

Posted: Tue Jun 21, 2016 1:57 pm
by mbigpops
Well I can tell you that putting the original long nuts back on solved my leaking issue on both ends.

Thanks Jim !

Another reason not to throw anything away until the end of the project.

Mark

Re: Oil Pressure Gage Fitting Dilema

Posted: Sun Apr 16, 2017 7:52 pm
by Riviera Wish
It's almost a year since my original post. I refer the reader back to the original photo of the compression fitting on the engine end of the oil gage connection on a 1952 Riviera. Just tried to hook-up the oil gage to a "standard" I/4" flare fitting and the threads are not compatible with the "original" CC ferrule. One of the responses to my original post suggested that the original CC ferrule was a WWII aircraft type compression fitting while another response suggested some standard male compression fittings would mate with the original CC female fitting in the photo. Today I tried to mate the original CC female fitting to a standard I/4" male compression fitting and could not get more than one turn on the threads; connection was 'loosey goosey". Can anyone tell me what the threads per inch (TPI) are on the original CC female connector? Are there male compression fittings available today that will mate to the original CC female fitting or must I change to a present day 1/4" compression fitting?
After a year of restoration I am almost ready for 'sea trials' any help with oil gage hook-up will be appreciated.

Re: Oil Pressure Gage Fitting Dilema

Posted: Mon Apr 17, 2017 9:50 am
by drrot
You don't want a compression fitting you want a flare fitting nut. They are NOT made to work together but they do.

Re: Oil Pressure Gage Fitting Dilema

Posted: Mon Apr 17, 2017 10:17 am
by jfrprops
what Jim Staib said.....correct....as usual....

John in Va.

Re: Oil Pressure Gage Fitting Dilema

Posted: Mon Apr 17, 2017 3:54 pm
by Riviera Wish
Brass Male Flare Fitting.pdf
(97.74 KiB) Downloaded 84 times
Thank you Jim and John for your responses.
First a little housekeeping. In my post of two days ago I talked about my 'one year restoration', actually it has been TWO years. Time really flies when you are having fun!
Now, please excuse my ignorance regarding brass fittings. I already have a collection of brass fittings that I ordered wrong and do not wish to add to my 'collection'. In this regard I have a few questions:

Male brass flare fittings appear to have a nipple on the end which would prevent the original CC female compression fitting from catching a thread (see attachment). No?
What is the size of the male flare fitting that mates to the original CC female compression fitting? 1/4 inch?
Do I need to machine the end of the male flare fitting in order to mate it with the original CC fitting?
Where can I purchase a 90 degree elbow that connects to the original CC fitting on one end and has a 1/8" NPT on the other end? This is what I need to hook-up the oil pressure gage to the engine.

Re: Oil Pressure Gage Fitting Dilema

Posted: Tue Apr 18, 2017 8:36 am
by drrot
You want the nut as shown in your first post. Install just as shown in first post. Bend the tube if needed. No machining needed.

Re: Oil Pressure Gage Fitting Dilema

Posted: Tue Apr 18, 2017 2:21 pm
by Riviera Wish
Jim, your statement, "you want the nut shown in your first post" is confusing to me. The long nut female CC connecter shown in the first post is what I am trying to connect to a mating male connecter.
Where can I get a connecter that will mate to the original CC female long nut shown in the first photo posted in this thread?
If no such connecter is available please advise and I will convert connection to a standard compression fitting.
Anyone have a used fitting that will mate to an original CC oil gauge fitting?
Picture of the long female CC nut that I am trying to make a connection with, that was posted originally, is attached again for convenience.

Re: Oil Pressure Gage Fitting Dilema

Posted: Wed Apr 19, 2017 9:07 am
by drrot
The nut connects directly to the gauge and the other end connects to the engine. If you need something in between use a modern fitting.

Re: Oil Pressure Gage Fitting Dilema

Posted: Wed Apr 19, 2017 11:43 am
by mbigpops
Okay this is like watching a bad tennis match ......

The oil pressure line fitting that you pictured normally goes to this "tee" fitting in the center of my photo on the right hand side. The other two "tee" ports come from the oil cooler and go into the block. The coil is removed in the photo (took a while to find this shot).

Do you still have this original "tee" for your engine ?

Mark

Re: Oil Pressure Gage Fitting Dilema

Posted: Thu Apr 20, 2017 12:11 pm
by Riviera Wish
Hey Mark,
The problem is that I do NOT have the original 'tee' connecter. I need to get from the long compression fitting shown in the photo to a 1/8" NPT. It's a long story but the current oil pressure pick-up is a female 1/8" NPT on the engine; so I need to get from the long compression nut to a 1/8" male NPT to make the connection. Basically I need to know if there is a modern connecter that will mate up to the female long nut compression fitting shown in the photo. I have tried a "standard" 1/4" tube compression fitting and the threads are different. Should I 'chuck' the original CC fitting and go with a standard 1/4" tube compression fitting to 1/8" NPT?
And the "bad" tennis match goes on. Hope someone can serve me an "ace"!
Steve

Re: Oil Pressure Gage Fitting Dilema

Posted: Thu Apr 20, 2017 3:48 pm
by Riviera Wish
In an effort to further clarify my dilemma, attached is a photo of my "mickey mouse" plumbing problem. In the foreground is the oil pressure gauge connection which is 'loosey goosey' because I can only catch a thread and get I/2 turn before the connection binds up. Apparently the plumbing problem was created by utilizing a pre-war engine block in rebuilding a post war KBL engine. At any rate the block is threaded for 1/8" NPT. The 'tee' in the photo that I am trying to hook-up to is a 1/8" NPT 'tee'.
If someone has an original 'tee' shown in Mark's photo and is willing to sell it to me I can make that 'work'. Please message me if you have an available tee fitting; or a fitting that will accept the original CC oil gauge female long nut.

Re: Oil Pressure Gage Fitting Dilema

Posted: Thu Apr 20, 2017 6:12 pm
by Riviera Wish
Here is photo to go with last post. Sorry, forgot to upload it with the post.

Re: Oil Pressure Gage Fitting Dilema

Posted: Fri Apr 21, 2017 7:58 am
by drrot
post another photo of the fitting with the nut off so it can be seen.

Re: Oil Pressure Gage Fitting Dilema

Posted: Fri Apr 21, 2017 11:35 am
by Riviera Wish
Jim, here are a couple of photos with the nut and tube removed. To get oriented, that black 'thing' is the bottom of the ignition coil.

Re: Oil Pressure Gage Fitting Dilema

Posted: Fri Apr 21, 2017 3:43 pm
by drrot
You are trying to put a flare nut on a compression fitting. Cut an inch off the end of the tube and get rid of the compression barrel and flare nut. Get a new compression barrel and compression nut.

Re: Oil Pressure Gage Fitting Dilema

Posted: Fri Apr 21, 2017 8:35 pm
by jfrprops
I agree with Jim. the fitting in the picture is clearly wanting a compression nut and the brass ferrule presently on the tubing no way it works with that flare nut. You have compression nuts on the other fitting shown just below the problem on in your pic.
???

John in Va.

Re: Oil Pressure Gage Fitting Dilema

Posted: Wed Apr 26, 2017 4:43 pm
by Riviera Wish
In the interest of retaining the original fitting on the oil gauge line I would like to obtain an original 'tee' fitting used by Chris Craft. The part number for that fitting, I believe, is 59-19000. If anyone has the desired fitting or a complete set of original oil cooler lines and fittings for sale please 'message' me a price. While I am far from being a 'pureist' I would like to retain originality for posterity. Some day this Riviera may get a post war KBL engine.