HELP!! oil tank connections 71 3.0 conversion

jpnovak · 01-17-2004, 04:02 PM

I am having on heck of a time trying to get my oil tank plumbed on my ST project. I am still out in the sleet trying to figure this out.

Here are the vital stats.

1971 T coupe. 78 ROW 3.0, stock engine oil cooler, stock Carerra cooler in fender well, stock hard lines from 78.

Here is the problem. I have three oil tanks and none of them will match up.

The 78 oil tank has the correct hose fittings to connect to the engine oil cooler (~2" S bend soft line with hose clamp ) and to the return line from the fender cooler (30mm threaded fitting). All would be fine and dandy but This tank will not fit into the fender well as the filler neck is on the wrong side of the filter mount.

The 71 tank fits in the fender but has the wrong connections. It has a 30mm threaded fitting for the return line and a 26mm threaded fitting for the inlet line. I have the hard line that goes from the tank to the inlet on the cooler but the 30mm threaded end and the 2" clamped end are not compatible. Likewise the inlet line from the thermostat (30mm) does not fit the 26mm tank fitting.

I also have another 71 tank with a female AN12 fitting on the inlet side of the tank. I did not want to get into AN lines.

Are there any adapters to go from the clamped line on the engine oil cooler to the 30mm threaded fitting on the side of the tank? What about on the engine cooler side? I guess the adapter would work in either place.

Are there oil lines that have a 30mm threaded fitting on the thermostat side and a 26mm fitting on the tank side?

Someone help me straigten this out. PLEASE

Thanks in advance

Tyson Schmidt · 01-17-2004, 04:14 PM

The smart thing to do here, is to install a '73 and later tank. You will need the extra capacity, and improved baffling with the new 3.0 liter motor.

You'll need to cut a new opening in the inner fenderwell to fit it. If you can trace the opening from another car, then you can transfer it onto your inner wall and cut the proper opening. The holes for the mounts are the same, so once the proper hole is cut, it will bolt right in.

chuckw951 · 05:29 PM

Try BAT inc. for adapters. In my case I used an early engine oil cooler on the 3.0 motor so that the early "S" hose would work with the early oil tank to then engine oil cooler. A special hose was fabricated to run from the oil scavange to the oil tank. I'm not running a front oil cooler at this point. Sounds like you'll need adapters and or some custom lines to get going, don't think you have the parts on hand to make it work. The '73 tank sounds like a plan.

This document has some good info about adapters, see page 16 for info about 911 oil line systems.
http://www.batinc.net/files/kits.pdf

jpnovak · 01-17-2004, 08:26 PM

Tyson,

I had thought about cutting the inner fender well to accomodate the 78 tank. I guess that will be easier than plumbing the older tank. Besides, cutting another hole makes the car lighter.

Sleet turned to snow. I guess tomorrow is out for the cut. HMM air tools work in the rain...

Both tanks look almost identical in size. Just from curiosity, What is the difference in baffling on the later style tank?

Thanks for your help Oh Evil One...

Thanks for the link Chuck. Another good reference. I will look there too but a circular cut is more timely.

Tyson Schmidt · 01-17-2004, 08:43 PM

The '73 and later tank holds about .8 quarts more. As far as the baffling goes, I really don't know, since I've never cut the two open and compared.
But I do know that when raced, the early tanked cars tend to spew oil into the air filter or catch-tank, and after swapping in the later tank, the problem goes away. The problem is always more severe in the early cars with larger motors swapped in.

The air hacksaw works really well for cutting the new hole. Some recontouring of the sheetmetal will be required as well, but it will be self explanatary.

Jim Richards · 01-17-2004, 09:42 PM

Didn't Chris (cstreit) cut open the oil tank on his race car (Phoebe) to modify the baffles? Might want to check with him, Jamie.

jpnovak · 01-18-2004, 05:23 AM

Yes, Chris did modify his tank. He added a baffle in the bottom to prevent starvation under hard braking. This would allow lower oil levels in the tank without consequence.

The air body saw. Eactly what I was thinking. I will go oil it up as soon as the rain quits. I can use the body seal as a template for mounting.

Tyson, Do you think the difference in oil spewage is due to the length of the filler neck. The vent line comes off the end of the filler neck. The 71 tank has a filler neck that is only about 4" long while the 78 tank is more than twice that. The 78 tank also has the filler more forward in the middle of the tank rather than to the rear of the filter mount. I could imagine that oil could back up into the rear corner and filler neck on the early tank causing some spewage. Just a thought...

Thanks again.