Oil cooler line question

[vilant]

Have a couple questions if someone doesn't mind helping out. Finally got around to do some maintenance and I finally discovered the cause of my mystery oil leak. Turns out oil is slowly leaking out of the bottom of one of the 2 oil cooler lines directly behind and a little below the oil filter. The way it ran down to the floor kept misleading me. So my questions are;
What is more common the nuts coming loose or the crimp going bad (can't tell which part is leaking)?
If I need to replace the lines, do I need 2 wrenches? One to hold the nut closer to the engine and spin the other. Or do I just spin the one and both come off? See pic below, arrows point to the nuts I'm talking about.

What size are these? They seem pretty damn big, larger then any wrench I have.
And finally, are these lines full of oil or just residual after engine is off for a while?

[carter200]

Contact Jerry at www.jerrysgaskets.com as he has what you need.....

[tccrab]

The oil leak almost certainly isn't the fittings, it's the hose itself.
Common failure on all LT5s.
GM used the wrong kind of hose, they should have used a silicon based plastic pipe and not a rubber hose.
The hose goes soft with age and oil just weeps through the wall of the pipe.
Easiest fix it to call Jerry. He has what you need, it won't cost an arm and a leg, and the really good news is that it won't take all day to fix the problem.

No need to drain the oil to change the pipes, just beg borrow or steal some big wrenches and loosen the upper fitting first and the oil will drain back into the oil pan through the lower hose.
You might have a few drips but you won't flood your garage floor.

'Crabs

[A26B]

Thanks for the referrals, they are sincerely appreciated.

I am in the process of manufacturing new oil cooler hoses in-house. The ones we were carrying in stock had 7% leakage rate. Consequently, we quit offering them. Nothing is perfect, but if the problem is chronic and cannot be cured, the I'm not going to stock it.

We will be making 2 styles of oil cooler hoses. One will be braided Stainless Steel with crimped connections and the other will be black, braided nylon with crimped, black fittings. The black ones are intended to be a close facsimile to the original hoses, but with much improved materials. Both hoses will be the same -10AN size as the OEM, so there will be no reduction in flow capacity, should the car be tracked and the oil cooler actually used.

Timing: I am finalizing arrangements with our material supplier, Russell Performance, so we do not yet have hoses in stock, ready for sale. All work will be done in-house and the hoses pressure tested for leakage before they are placed in inventory. I will post here on the forum when they are available.

Once again, thank you for the referrals.

[mike100]

Originally Posted by A26B

I am in the process of manufacturing new oil cooler hoses in-house. The ones we were carrying in stock had 7% leakage rate. ...

Were those failures infant mortality? My set is working fine- will leave them alone if this is the case.

[A26B]

I didn't keep track of the failure timing, probably somewhere in the 2~6 month range.

[vilant]

Thanks for info Tom, it is appreciated. I've bought from Jerry before and actually have a small list of items I was going to purchase soon anyway. I'll have to find a band-aid until Jerry gets the new lines in.

[PhillipsLT5]

Russell is Performance

[Dynomite]

How to make your own SS Braided Hydraulic Lines with reusable fittings

Tools: One 10 inch cresent wrench (Box Wrench is best), One vice, Air compressor, Angle Grinder (with Cut Off wheel). The best tool for cutting the SS Braided Hose is a Small Angle Grinder (with Cut Off wheel) which does not fray the SS braids on the hose ends. It is also best to use an appropriate size Box Wrench on the Hose Fittings (box end) to minimize leaving marks on the fittings. I use Aeroquip Reusable Fittings and SS Braided hose from Summit Racing.



1. Place SS Braided hose in vice and cut SS Braided hose to length using Angle Grinder with Cut Off wheel. Angle grinder is preferred since minimal SS wires are left free of the cut.
2. Make sure no SS Braided wires enter the hose end and make sure all loose SS Braided wires are ground flush with end. Keep the hose in the vice with about 2 inches on the free end out of the vice. (Clean the inside of the hose end Cut Off before going further with Cotton Cue Tip .
3. Take the AN reusable hose fitting and unscrew the male part from the female part. The other end of the male part will have an NPT pipe thread or "O" ring seal thread size (AN) as desired.
4. Take the AN reusable hose fitting female part and screw onto the SS Braided hose (counterclockwise) by hand pushing onto the hose as you rotate the female hose fitting counterclockwise.
5. Screw the AN female reusable hose fitting onto the hose such that the hose is at a depth into the female fitting as defined by the lines on the female fitting surface.
6. Lubricate the inside diameter of the SS Braided hose with oil through the end of the female fitting.
7. Insert the male reusable hose fitting into the lubricated hose through the end of the female fitting.
8. Push the male fitting into the hose as you rotate the male fitting clockwise using a cresent wrench (Box Wrench preferred). Once the threads are caught, continue rotating the male fitting into the hose untill approximately 1/16 inch space is left between the hexigon of the male fitting and female fitting.
9. Install the second hydraulic reusable hose fitting on the other end of the hose as per steps 2 through 8 above.
10. Last...but not least....take an air hose (Air Compressor) and blow the hose clear to make sure you have a clean assembly (if the SS Braided hose is not too long look through the hose end to end for any debree). You now have a SS Braided hydraulic hose with fittings good for maybe 2,000 psi hydraulic pressure more or less.

Parts Required for SS Braided Oil Cooler Lines.

The SS Oil Cooler Lines are very easy to make up in SS Braided hose using Aeroquip reusable fittings and SS Braided hose available from Summit Racing.

1. Use two 10 AN Stainless Steel Braided hose.
2. use two Aeroquip Reusable Hose Ends, 90 Degree, -10 AN Hose to Female -10 AN, Aluminum, Nickel Plated.
3. Use two Aeroquip Reusable Hose Ends, 45 Degree, -10 AN Hose to Female -10 AN, Aluminum, Nickel Plated.
4. Use two Stat-O-Seal, 5/8 in Inside Diameter, Aluminum with O-Ring.
5. Use two 10 AN M18x1.5 fittings threaded into the Aluminum adapter manifold.
6. One 6mm x 1.0 x 35 mm SS Allen head bolt.
7. One 6 mm SS washer.
8. Two "O" rings for the Aluminum adapter manifold to oil cooler interface.

The first five items can be found at Summit Racing.



As an aside, I use the similar Aeroquip reusable fittings and Aeroquip 1509 hydraulic hose on all my farm implements and tractors. I make up all my implement hydraulic lines often replacing relatively new lines that come with the implements with my own lines that are much more dependable under extreme usage. We are talking hydraulic pressures over 2,000 psi on the hydraulics of some of these implements when the cylinders reach the stops.

Once you experiment with making your own hydraulic lines with some using SS Braided hose you will never look back at buying ready made hydraulic lines again. All you need is a vice, hand grinder (or even a hack saw will work), and a couple box wrenches of appropriate size. Oh...and an air compressor to blow clean the lines after assembly.

[cvette98pacecar]

If you need a set in a pinch let me know I have three sets and would sell you a set for what I paid for them from Yun.