Oil Line Removal

[Steam Driver]

I'm needing to remove the oil lines in the LR fender, to and from the engine/oil tank to the front cooler. As I've read someplace here before, they seem to be "welded" in place. I've tried limited heat on the tank/thermostat line fitting at the T-stat (the one at the tank was no problem) with no luck. Next stop is a cheater bar on the wrench, but along with that, how much heat can safely be used?

FYI I need to remove that one so I can get to the one from the engine to the T-stat, which currently is an Aeroquip hose put there when the P/O swapped the SC exhaust system for the early model in search of more power. For my area I need the cat back on the car.

I'm sure a lot of people have dealt with this before swapping out T-stats and such; what's the secret if there is one?

[Ayles]

Once you have tried everything with no success you can carefully cut the nuts off with a dremel and replace the line or use elephant racings nut kit. I had to cut both nuts on the engine side of the thermostat. I fought with them for a couple weeks before cutting. They just wouldn't budge.

Oil Lines

[poorsha]

I removed the entire oil line system from the car first.
I found the front lines connected to the loop cooler (78SC) were more accessible and came apart easier. This made it easier to remove the complete system.
Then I mounted them in my portable work bench and they came apart much easier.
I also invested in the correct oil line wrenches.
Good luck.

[pete3799]

Originally Posted by Ayles

Once you have tried everything with no success you can carefully cut the nuts off with a dremel and replace the line or use elephant racings nut kit. I had to cut both nuts on the engine side of the thermostat. I fought with them for a couple weeks before cutting. They just wouldn't budge.

Oil Lines

^this.
If they won't break loose by hand.......cut the nuts. Don't use a cheater pipe as you'll likely peel the threads off the thermostat $$$$.
Mine wouldn't budge either. Slice the nut carefully so as not to get into the threads.
If you nick them a little you'll still be alright as the hose seals on the end not on the threads.

[JINKATIN]

Using a cheater bar was the way I was able to remove them, its a little tricky but it can be done.

[JJ 911SC]

Even with the whole system removed and using a large pipe wrench the two nut on the thermostat would not move... So before ripping out the threads, I split both nuts using a Dremmel and use the Elephant Nuts as recommended below by Ayles and pete3799. Not a drip after 3 years.


Pelican Parts - Product Information: ERMP-0170000




Before




3 years later

[911pcars]

A challenge good auto techs encounter is to perform repairs w/o destroying car parts. In some cases, damage is unavoidable, but aim for that goal.

In the case of the external oil lines, follow Poorsha's suggestion and remove the entire circuit. That way, you're not encumbered with access issues and invoices for replacement parts, costly or otherwise. As with all stubborn threaded fasteners that have been intimate since day 1, apply heat and a thread penetrant (Kroil or equivalent). Use the right tools on both sides of the connector to hold and rotate (longer levers acceptable). Do this before breaking out cutoff tools and pipe wrenches. During re-assembly, apply antiseize to seizable joints.

Sherwood

[Steam Driver]

How much heat can be safely applied? Map torch, or red hot w/acetylene?

[fanaudical]

Be careful with heat as you still have oil residue inside. Too much heat and it may ignite.

I was successful with a propane torch and running through a couple different heating cycles. (Heat one side, let it cool, heat the other side, let it cool, heat in-between, let it cool, etc).

[mdwracer]

Don't use heat , I cut mine with a 90 deg air grinder ....make a slit down the nut then take a chisel and insert it in the cut slot and hammer it wider while hammering in a loosening rotation...this splits the nut a bit and it works every time and I've done several over the years as a technician in shop situation, after trying the heat thing and only doing a bunch of damage to the stat the first times.
I only do this to the two lines from stat to engine and tank then they will be replaced.
Good luck,
Mike

[911pcars]

Originally Posted by Steam Driver

How much heat can be safely applied? Map torch, or red hot w/acetylene?

I suggest using a propane torch. Map and acetylene can also be used, but if inexperienced, one can overheat and melt metal. Heat the female part to a dull red (if steel). Be aware of surrounding areas, another reason to perform this off the car.

This video stresses torch safety as much as anything.


Apply penetrating oil to the threaded joints as the parts expand from heat. Let cool slightly from the red hot state, then attempt to loosen. Repeat as needed. Always use two wrenches to avoid distorting tube connections. Patience is required here.

If hopelessly petrified, as is often the case with exhaust fasteners, you can always resort to slicing the female hex with a Dremel abrasive disc or equiv. to loosen its grip on the male thread. Again, use penetrating oil.

Sherwood

[tributeventures]

Interesting issue.
I recently had to remove my oil lines. A VERY knowledgeable Porsche mechanic told me the secret. Here it is:
Do not use heat or cut the nuts. Spray the nuts with "Blaster" , let sit and then tap the flat on the nuts with a hammer and punch. Spray again, let sit and then tap again. It may take a while (days) but eventually the nut will loosen and you can then remove the lines.

[kodioneill]

It's obvious from reading this the way to go is to cut the nuts, it's the foolproof solution.

[Luislang]

I've just gone through this exercise on a 1976 911 rebuild. After days of heat/blaster/tapping with no discernible result, I made peace with the fact that I'll have to replace the thermostat ($359 on ebay). The reason being that splitting the nuts on the brass lines was not an option, as that would require replacement ($1200) of the brass lines. (Unless you had some replacement nuts lying around and be OK with cutting/soldering the lines).
The pipe wrench and 6' pipe extension in the bench vise got the nuts to move by shearing off the aluminum threads. Removing the aluminum from the threads in the nuts was accomplished by heating nut with mapp/oxygen, and digging out with a sharp awl. Be careful to insure it is all removed, as not to wreck threads on shiny new thermostat.

[JJ 911SC]

Originally Posted by Luislang

... with the fact that I'll have to replace the thermostat ($359 on ebay). The reason being that splitting the nuts on the brass lines was not an option, as that would require replacement ($1200) of the brass lines. (Unless you had some replacement nuts lying around and be OK with cutting/soldering the lines)...

Any reasons why the Elephant Racing 30mm Tube Nut Replacement would not have work in your application?

$50 per nuts, 5 minute to install, no cutting/soldering the lines. Pelican Parts - Product Information: ERMP-0170000

[Steam Driver]

OK I started this thread. Here's my progress (finally)

I was successful in getting the tank to T-stat oil line nut loose at the T-stat tonight. Hurray! Kroil and heat were part of the trick BUT I also did something else.

I put a bunch of ice cubes in a shop rag before I started heating with the MAP gas torch. When I had heated the nut long enough to where the rear fender beside and above the T-stat began to feel warm to the touch, I stopped heating and then applied the ice pack to the aluminum thermostat. When it had steamed and melted a little bit I applied the wrench, no cheater bar, and applied steady pressure and it finally began to turn and came off fine.

If the ice bag hadn't worked, I was going to try dry ice, available at a local grocery store, next.

Anyway that one's out of the way, now I can work on the engine to T-stat assembly.

This has probably been thought of before but I've not seen anything about it on the forums and one can't have too many "tools" in their bag of tricks!

[ADDvanced]

Originally Posted by JJ 911SC

Any reasons why the Elephant Racing 30mm Tube Nut Replacement would not have work in your application?

$50 per nuts, 5 minute to install, no cutting/soldering the lines. Pelican Parts - Product Information: ERMP-0170000

Once you cut the old nut off, how would you install these new nuts over the old lines without cutting and soldering? I am not clear how you would get these over the factory lines.

[juanbenae]

Originally Posted by poorsha

I removed the entire oil line system from the car first.
I found the front lines connected to the loop cooler (78SC) were more accessible and came apart easier. This made it easier to remove the complete system.

what he said.

[Rawknees'Turbo]

Originally Posted by ADDvanced

Once you cut the old nut off, how would you install these new nuts over the old lines without cutting and soldering? I am not clear how you would get these over the factory lines.

I have not seen one of those in person, but based on the pic, the new nut's inner diameter clears the flare end of the pipe, and the washer, which is expandable (it is open ended and wound - not a typical solid/closed circle), also clears the flare when expanded and is the surface that the nut uses to apply pressure to the flat portion of the flare end.

[JJ 911SC]

Yes and Yes.

Remove system from car if you can.

Put the nut first and thread in the washer (like a key ring).

Has not leak since.