lnlangley

Hi everybody! Just about to pull the engine for rebuild and have finished removing just about everything off of the 72 coupe base 350 engine. One last thing to remove. As I was trying to remove the small plastic oil pressure guage line from the upper rear block boss, I discovered that there are two brass fittings involved. The top fitting (3/8") screws into another brass fitting (7/16") which is screwed into the block much like the fuel line fitting into a carb fitting. Thinking this little task would be simple, I took my 3/8" flare wrench to the top fitting thinking that the line would come right off. Wrong. The top fitting came off ok but the plastic line has a threaded metal end attached to it which appears to be solidly attached into the bottom brass fitting. It will not pull out whith a gentle tug.

My question is, do I also need to remove the bottom fitting from the block? I tried getting my 7/16" flare wrench on it, but there is not enough clearance between the intake manifold and the bottom fitting.
I have thought of two possible solutions. Try to find a very thin (and short) flare wrench or remove the intake manifold in order to get on the bottom fitting. Any advise would be sincerely appreciated.

The last thing I want to do is damage or break that plastic line or its fitting to the engine. What a PITA fix that would be! I thank all of you and really enjoy this forum.

Larry
Austin, Texas

grybdn

here's my 2 cents.

You could try a small vise grip, or just keep trying with your wrench, a little at a time.
You are correct, it's a PITA to fix the oil pressure line behind the dash. I have a 71 and broke mine trying to tighten the tach cable.
I would just brake it off on put a new line on it , you don't want it to brake after you have done all of your work.

fotyfobravo

The original nylon line gets brittle after a few years. I know it's not stock, but I recommend replacing it with COPPER line. NAPA sells a nice copper kit with all new compression fittings. There should be a junction prior to entering the firewall that will connect to the new copper line. Just be sure to put a few vibration loops in the new copper line. A small RX bottle makes a good pattern to make the loops. About 4 loops will absorb any vibration and the copper will not surprize you with a high pressure oil leak .

Edzred72

There is a brass ball on the end of the plastic line, and is sealing part of the compression fitting. If you've removed the brass "cap" the line should pull straight out. Wiggle, gently twist, and pull. Overtightning can mash that ball seal down into the 7/16" block fitting but it should come out with some coaxing. If the plastic line breaks....you needed a new one anyway.
Good Luck
Eddie

DJ Dep

Snip the line at any convenient point and replace it. Much simpler and easier to do. I don't think you have to worry about getting a correct "numbers matching" plastic line. But I'm also sure they exist and Ecklers has it

Dep

Gordonm

Never use a copper line for this fitting. The copper line will fatique from the vibration and will break. Use either the plastic line or get a braided line ($$$). The braided line will last forever. The plastic lines last until they get bumped hard then they can break.

Once you have the top brass nut off the brass ferrel will come out with some effort. Like others have said you can just snip it and replace it.

lnlangley

Thank you members who replied to my question. I just wiggled the thing around and very gently put a pair of small narrow vice grips on the very upper edge where the plastic tube goes onto the pressure fitting. A little tug and twist and it was out before I could say it. No damage to the fitting or the plastic tube.

The recommendations about replacing the tube are appreciated and probably indicated after 33 years, but I just buttoned up the dash after a heater core replacement and really did not want to go back in there.

Larry

grybdn

Your problem my come when you re install that tube. If you don't get it back together correctly, it's going to look like a fountain of oil, when you crank it over. Oil Oil, everywhere. Happend to me.

foundvettelifeisgood

It's especially nice when the line breaks under your dash and your front carpet and one shoe are ruined. That line also runs directly over your radio, so their is the possibility of catastrophy. It's a horrible design. I got the replacement from Zip.

Jughead

Or you could use the SS braided version. I don't have it connected directly to the gauge though. I spliced it to part of the original plastic line coming out of the gauge. I'll connect it directly when I have the dash apart.

DJ Dep

Hey Len...is the SS braided sold as a complete kit?

Dep

Red 69

That braided line looks like a bulletproof solution. Did you run it through the stock firewall grommet or somewhere else? A kit would be nice.

Jughead

Yeah, it's sold as a "kit" from Jegs, I think. I think it's available as a 2 or 3 ft kit. $29 though, a little on the high side compared to a $8 plastic line kit. The fittings are already attached so all you need to do is bolt it on.

Eddie70 also has one and was trying to attach it to his gauge without luck though. I have mine running up the engine block and then connected to a short piece of the plastic setup right before it enters the firewall. That'll have to suffice until I rip apart the dash and see how it attaches to the gauge.

I think Eddie told me he needed a -3AN type fitting. They're not common but you can find -3AN.

Here's a picture where I had it connected to an oil pressure gauge when I "primed" the engine. I'm sure there's gotta be some type of fittings to attach it to the Vette gauge.

lnlangley

Thanks again folks for the replies. Truthfully, I didn't think anyone would be interested. Your advise has been good - a positive outcome with no damage as a result! For a "mechanic" (can you say accountant) like me damage control is very important. After I get all of the pending tasks done with this car, I shall probably go back into the dash and replace the plastic line to the guage. Damn sure don't want oil spewing all over the place, especially the inside. Never thought about this matter until now. Always something!

Larry