FIXING (slicing) oil lines?

[davis911s]

I just did a good check of my oil lines going to the front cooler, sure enough as you guys thought, pinched! Can these be fixed or spliced or anything? they are DAMN expensive for a little line!

Shawn

[Early_S_Man]

Shawn,

The hard lines are brass ... a copper junction or splice can be soldered in to replace the damaged section. Not pretty, I suspect, but painted to match the other part of the line ... it might not be so noticeable. Or expensive as a new part!

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Warren Hall
1973 911S Targa
1992 Dodge Dakota 5.2 4X4 parts hauler

[davis911s]

Excellent, thanks again Warren, my car is not by any means concours and who else looks for pretty stuff under the car anyways!

Shawn

[not_sure]

So Warren, your saying I could build a set of hard lines with some copper tubing? If so, what ID? Ive been looking into adding a cooler up front but did not want to use braided tubing.

Tom

[Early_S_Man]

Tom,

No, I was only suggesting copper as a relatively easy repair, doable at home with a propane torch.

Copper is entirely too fragile to use for an entire front cooler system! For a scratch-built low-cost system, I would recommend using thin, steel hydraulic tubing in the 22 mm size (same as the factory lines) from Metric & Multistandard Components Corp. It is capable of being bent like conduit, yet is pressure-rated, even in the thin 0.5 mm wall thickness.

http://www.metricmcc.com/



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Warren Hall
1973 911S Targa
1992 Dodge Dakota 5.2 4X4 parts hauler

[davis911s]

Warren, reference the copper tubing, once I got the line out I noticed other kinks. I would need to replace about a 2 foot section. Would the copper still be okay for this? What about any contaminents going in the oil etc?

I also emailed you this question, hope you don't mind, just a pain with the car off the road.

Thanks again

Shawn

[rattlsnak]

Why dont you just the replace the whole line with a stainless braided type? Ive ran all new oil lines everywhere. The fittings are @ $20 each, and the hose is @ $6.00 a foot.
Here is a link to Aeroquip.

http://www.aeroquip.com/pages/prodinfo.html

[Alan Herod]

I considered this as a solution, but rejected it for heat concerns -- since I have continued to work with what I have to extend performance on the track, I have not added the new cooler yet. I believe that brass lines do a better job of disipating some of the heat then the braided stainless steel lines due to the lining.

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Alan
83 SC

[beepbeep]

Rattlsnak:
I just saw nice socketless hoses on Aeroquip page. I'm planning to change pinched lines on my 930 with either copper-tubing or flexible hoses. This "Socketless" hoses seem like pretty good idea (as it doesn't involve too much work, i could probably do it myself), but i wonder of those "socketless" connection can stand to 5 bar pressure and 120 deg. C temp?

What is the best solution for aftermarket 930 forward-cooler tubing?

Thanx!

[Bill Verburg]

Copper pipe comes in various wall thickness designated by the letters K,L,M in order from thickest(strongest) to thinnest walls. I have seen .75" K pipe(which has the additional benefit of being somewhat flexible, it comes in coils rather than lengths) used to successfully repair/replace pieces of oil line.

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Bill Verburg
My Home Page My Pelican Gallery page My Porsche Owners Gallery Page

[rattlsnak]

well, all I can say is that every race car you will ever see has (including nascar, F1 etc) uses some type of fittings like these, whether it be Earls, or Aeroquip, or whoever. Copper, I'm sure is great, but these lines are VERY easy to work with, and the socket type are very easy to install.

[911pcars]

I've always wanted to try this repair with my oil lines, bike frame or exhaust system, which for the moment are not dented; but I can always hope :-)

To do this, you'll have to remove the line(s) from the car. If it's not mangled too badly, try drilling an appropriately sized hole(s) opposite the dent, then gradually work the metal outward using a hammer and pin punch through the opening. If you have a shot or bean bag to support the tubing, so much the better to avoid thinning the metal too much.

This is sort of like miniature body work from the inside. Once it's pretty close to original shape, braze a small patch over the drilled hole(s), clean thoroughly, then reinstall. This technique might look cleaner and less noticeable than splicing in an entire new section. Be careful as the metal is relatively thin. If you get overexhuberant, you'll have more holes to patch. But for the cost of a replacement line, what's a little time? You're developing new skills.

BTW, does anyone think a "paintless dent removal" technique might work?

Sherwood Lee
http://members.rennlist.org/911pcars

[Clark Griswald]

Sherwood, that is an interesting idea if the tube is not too flat.

I am a bit concerned about the residue that would be left inside the oil line after welding. Although you would pour out the oil first, the inside of the line will be coated with oil that will burn when welding. The residue will be left behind.

I suppose it will get picked up by the filter, but I just don't feel good about it.

Does the oil pass through the filter before, or after the oil cooler lines? I think it is before which means any residue would go straight into the engine before it gets to the filter.

Perhaps the line could be cleaned out first with a water soluble degreaser like Simple Green. Fill the oil line with this stuff, then hose it out?

If you cut the line first, you can reach in with a rag and wipe out the oil inside the tube, minimizing any residue.

Another idea for midly dented lines:
If the dent is less than half way (less the the radius) you might be able to squeeze it back into shape. Take a peice of rigid pipe (cast or steel) that has an inside diameter about the same as the oil line outside diameter, cut that pipe lenthwise creating two half pipes.

Now pinch the oil line between the ridgid half pipes with a vise to squeeze it back into shape. You are using the half pipes like a mold.

I haven't tried this but it seems like it would work for mildly dented sections.



[This message has been edited by Clark Griswald (edited 08-16-2001).]

[cstreit]

By the by, the pressure in the ENGINE is 5 bar, pressure in the front oil cooler is typically much less...