'83 SC External Oil Line Removal

[gopopracing]

Having difficulty in getting the external oil lines, running from the Oil T-Stat to the oil tank and hard engine oil line, removed. The 36mm nuts which attach the lines to the Oil T-Stat will not loosen. Have been soaking with PB Blaster and occasional heat with a Propane Torch, still no success. I am being careful not to damage anything or cut the nuts and damage the threads on the Oil T-Stat.

Having read several posts on this subject and have yet to find on that really suggests, or gives good guidance on the most successful way to accomplish getting the 36mm Nuts to release. My car is all original with 103,000 miles and these lines have never been removed.

Thanks for any assistance and reputable advice.

[Steam Driver]

First off get a 36mm crowsfoot wrench. If it's a tubing version so much the better. This allows you to adjust your lever on the wrench to more useful swing angles than an open end wrench in the confined space available. The use heat and Kroil or PB blaster. Don't be afraid to heat it a lot. There's nothing in the T-stat that will be damaged (after all dealing with heat is it's function), and a lot of the heat is being syphoned off by the AL casting anyway. But I thought the key was the crowfoot. You will probably have to get it on-line.

Although it may be helpful you don't really have to try and loosen the nut while it's hot. The heat and resulting expansion cycle should help break the corrosion bond between the nut and the T-stat. Use anti-sieze when reassembling it. Something the Germans seemed loathe to use anyplace when assembling the cars.

[boyt911sc]

Originally Posted by gopopracing

Having difficulty in getting the external oil lines, running from the Oil T-Stat to the oil tank and hard engine oil line, removed. The 36mm nuts which attach the lines to the Oil T-Stat will not loosen. Have been soaking with PB Blaster and occasional heat with a Propane Torch, still no success. I am being careful not to damage anything or cut the nuts and damage the threads on the Oil T-Stat.

Having read several posts on this subject and have yet to find on that really suggests, or gives good guidance on the most successful way to accomplish getting the 36mm Nuts to release. My car is all original with 103,000 miles and these lines have never been removed.

Thanks for any assistance and reputable advice.

If you could not get the 36-mm to the oil thermostat to come loose after soaking it with penetrating oil, heat, etc. over a long period of time, do not force it. You would likely stripped and damaged the aluminum thread on the thermostat. Rendering the auxiliary thermostat unusable.

An option you have to decide is to remove the oil lines assembly between the oil tank and cooler from the car and continue the disassembly on the bench. This will give you better chance to get the stubborn 36-mm to move. Do not use brute force! The corrosion between the 36-mm steel nut and the aluminum threaded section of the auxiliary thermostat is a known problem. The galvanic reaction between the steel and aluminum causing these two different materials to bond and fused together.

It all now depends on the degree of bonding between the steel & aluminum. Be patience and do not force it. You will regret after you stripped the thread. If after all your efforts failed, a proven and successful trick is to cut the 36-mm nut to save the auxiliary thermostat. Replacing the 36-mm is cheaper than replacing the auxiliary thermostat.

First, try to loosen the nuts at the oil tank and at the oil cooler. They are usually less troublesome than those at the thermostats. Good luck.

Tony

[gopopracing]

Thanks "Steamdriver" I really appreciate your help! A lot of patience and a 36mm Crowfoot seems to be the answer.

[G450X]

When I installed my SSI’s, I thought that 36mm nut on my high mile ‘82 SC would never come off.

I used mapp gas, a few shots of kroil, and a dedicated 36mm line wrench - it finally broke. Like all difficult projects, a good time to celebrate with a favorite beverage.

Many thousands of these have been installed, hang in there!

[targa80]

Many years ago ~ late 1990’s I had an issue with with a line from the oil tank to the T-stat that I needed to replace. I could not break the T-stat connections so eventually removed the T-stat and the trombone with the interconnecting lines as one assembly. Using heat and penetrating oil I was able to break the connections on T-stat but the threads were shot due to the connection of dissimilar metals. Ordered new T-stat and reinstalled the entire assembly. I can say that that was not a fun project to take on.

[Flat6pac]

Use a high speed cutter and cut through the nut diagonally
Air chisel the nut to break it loose
All threads are released and just take the nut off thermostat
New line is required but the thermostat is saved because the threads on the thermostat will come off when nut is forced.
Bruce

[gopopracing]

Thanks. I understand to make a diagonal cut across the flat of the nut (/), so as not to be parallel to the thermostat threads?

Thanks again and I appreciate your help and many articles along with your Performance Handbook.