Oil tank has small leak

flash951 · 09-09-2013, 07:12 AM

Oil tank has a small leak, seen from the ground and up. Can I make a quick and dirty fix without remove the oil tank. Drain the oil, sand/grind the area to bare metal and apply some two component "chemical metal"? Will the JBWeld do, or is it to liquid to use and will reins off? Please help me out what to do.

Decolliber · 09-09-2013, 07:16 AM

Are you sure the leak is not coming from the cork gasket on the oil level sender?

wildcat077 · wildcat077's Garage

JB Weld will work,i used it a few times on fuel tanks and it held,just make sure the area is clean and free of oil contamination.

Cheers
Phil

ossiblue · 09-09-2013, 07:25 AM

From your pictures, it looks like the leak has already been "fixed" once using some kind of patch. The second picture, especially, looks like a rough, unsanded compound has been applied and painted over. From the look, it appears a PO tried the same thing you are considering--fixing the leak without removing the tank. If that's the case, then I think you'd have to remove the tank to do a complete and secure repair. Just draining the tank and sanding the area probably won't be enough as you would need to be sure no oil remains in the patch area and on the metal. If it turns out the tank was previously patched, I'd bite the bullet, pull the tank, remove the old patch and have the tank welded/brazed for a permanent repair.

docrodg · 09-09-2013, 07:35 AM

JB Weld will work, I just used it on the diff cover for my 5-ton chevy that had a pinhole leak. Clean well, mix up the jb and wait a few minutes before applying so it is a little stiffer. While a new tank is a better solution (or a soldering or brazing fix) the JB does work and is much cheaper.

Sunroof · 09-09-2013, 07:40 AM

I went through the same thing, but my tank leak was where the brackets that hold the bolts that go onto the body had a crack. Your better off taking the tank off, cleaning it, going over the entire thing with patch welding if necessary and re-coating. I took mine to a radiator shop for a hot solution cleaning, had the leak welded and added a couple of coats of POR15. Added anew cork gaslet for the new sending unit and no problem since then.

If however, your intend is to do a fast and dirty patch job, MarineTex is much better. Its a two part epoxy that will seal cracked engine blocks!! I am sure though the area has to be clean and free of oil, this is why your better off just removing it and doing it right. One word of caution..........................on my 1973.5T I had to remove the lower valance on the fender below the bumper to take the tank down.

Good luck

Bob
73.5T

flash951 · 09-09-2013, 02:57 PM

Thanks, I'll try it quick and dirty fix with JBWeld first. I'm afraid the oil lines is a bit hard to loosen from the tank.

flash951 · 09-15-2013, 02:22 PM

I have now loosed the tank, the lines was not to hard to loosen. Is there some sealings that should be replaced for the hoses and lines?

zippy_gg · zippy_gg's Garage

Quote:

Originally Posted by flash951

I have now loosed the tank, the lines was not to hard to loosen. Is there some sealings that should be replaced for the hoses and lines?

There were no seals or rings on my 86 Carrera, but the "S" hose was dry and cracked and eventually would have failed. This may be a good time to replace it.

safe · safe's Garage

That tank may be junk.
Keep in mind that any crud or rust in the tank will go straight to the pump and bearings...

Clean it, cut away the rust, then you can probably see the inside of the tank better. Then braze a patch for the the part you cut away.

RWebb · RWebb's Garage

any JB Weld fragments that ever come loose can also make their way to the engine

Ayles · 09-16-2013, 01:04 PM

Not sure if you have this option locally, but I just got my oil tank back from Pacific Oil Cooler and they bead blast and test. They can tell you if a repair is needed and if it's fixable. They also do an amazing job at cleaning and painting the tank.

See my thread on it here:
Oil Tank Unboxing

safe · safe's Garage

Quote:

Originally Posted by Ayles

Not sure if you have this option locally, but I just got my oil tank back from Pacific Oil Cooler and they bead blast and test. They can tell you if a repair is needed and if it's fixable. They also do an amazing job at cleaning and painting the tank.

See my thread on it here:
Oil Tank Unboxing

What did they do to the inside?

I have seen tanks that are very nicely restored on the outside, that's full of rust on the inside.

Ayles · 09-16-2013, 01:44 PM

They run it through an ultrasonic cleaning process. Mine was run through the process twice. In the status call we had they indicated it was very dirty inside. I did not have any rust though.

I can verify that it looks brand new inside as well.

flash951 · 09-25-2013, 06:10 AM

Thank you for all input. I have a "bad" oil line from the tank to the engine as well. Maybe the original line was difficult to put in place because I have a 2.7l with 3-1 backdated heat exchanger. I think my oil tank is for the original 2.2l (-71) engine. Is it possible to replace this oil line, this part? What part in Pelican shop will fit?

BoxsterGT · 09-25-2013, 09:27 AM

I wonder if this oil hose routing and the support strap (circled) has contributed to the leak you have. Its a very unusual way of doing it, as normally it goes forward from the motor then turns up and over the trans and then back to the tank.

A replacement hose is available from our host. It is PN 901.107.331.12 and is $107 US. But before replacing it I would do whatever it takes to route the hose properly, even if it means a replacement heat exchanger. Cannot tell from the photo. Do you have any heat at all on the drivers side?

Len

RWebb · RWebb's Garage

you should "scrutineer" that car as there is no telling what else some PO has done to it...

flash951 · 09-25-2013, 11:26 AM

Thanks again from inputs. I have no heat connected, as I miss an external oil cooler. I use all air from the fan to cool the engine.

BoxsterGT · 09-25-2013, 01:20 PM

The system was designed for L&R heater boxes. When its hot outside, you don't need heat. The heating system is closed. This does not limit the engine cooling.

Guess you only drive this in warm weather. No need for defoggers in the rain?

Regardless, a proper fitting and operating oil system is important.

Len

flash951 · 09-25-2013, 02:29 PM

Boxter GT, on the early 911s, the same fan used to cool the engine is also used to blow air to the compartment. When blocking this air, more cool air are used to cool the engine. This is a normal modification. The fan in the front compartment blows cool air to the front window to defog. Of course it's cold outside, but the engine is more important than the level of comfort. And thanks, I think all people in this forum agrees that having a working oil system is important for the air/oil cooled engines, thanks.