Need advice on pin hole in steel hydraulic line JD 755

[rly]

I have a Deere 755 compact tractor and there is a wear spot and a pin hole in a 5-ft steel suction (return?) line from the oil cooler, which is behind the radiator. The hole is roughly under the seat area and is accessible from underneath. It's fairy low, near a drive shaft protective sleeve. I can undo both ends but can't snake out the line without probably taking out a whole lot of other stuff first. It has several problematic bends. Can I:

1. Just have a hydraulic hose made up with the correct fittings and abandon the steel line. Won't be as durable but I assume it would hold the pressure and heat and would get us up and running.
2. Braze the pinhole in place, with care. I've used white flux coated (brass?) rods in the past for other things.
3. Cut the line at the leak and use a hydraulic compression (not flare) union; they seem to make such things. The steel line is a few thousands over 1/2' so I'm guessing it's 1/2' and the rest is paint.
4. I don't imagine there is a clamp-on patch, like for water pipes, that is for straight steel hydraulic tubing. Or is there?

Thanks

 

[BeezFun]

If you read this thread, it covers many thoughts on how to fix a hydraulic line.

 

[3 Horse Ranch]

TractorData.com hydraulic pressure for a John Deere 755

Pressure:

2050 psi 141.3 bar

I would think a half inch steel line is a pressure line, so if you can find a fix that will take that pressure all will be good. Otherwise, you might have some wrenching to to

 

[rly]

Thanks. I was wondering what type of pressure we were dealing with.

 

[orezok]

I seriously doubt IF it is a cooler line that it is anywhere near hydro pressure. The cooler would explode.

 

[RickB]

Thanks. I was wondering what type of pressure we were dealing with.

You stated it was a return line and if it connects to the oil cooler it likely is. Max pressure will be in the 200psi range. Oil coolers will not stand system relief pressures nor are they asked to.

 

[rly]

I wondered about that. The oil more oozed continuously out of the pin hole rather that shot like a stream.

 

[rly]

Still, JB Weld is probably not the answer!

 

[RickB]

Still, JB Weld is probably not the answer!

Probably not.

 

[newbury]

wrap some rubber around it and tighten some plumbers clamps?

 

[rly]

If were just a pin hole, maybe, but there is a large scooped out area that the pin hole is in the middle of. I'm beginning to entertain the idea of a hardware store brass 1/2 x 1/2 compression union.

 

[rly]

I'll check NAPA for a better 1/2 x 1/2 compression union than a hardware store one.

 

[K5lwq]

I have had good luck with the hydraulic compression fittings. As long as you have the room that is what I would suggest. But I would use one made for hydraulics.

 

[rly]

Yes, I'm looking for 'high pressure' one as opposed to brass plumbing/fuel line ones.

 

[K5lwq]

If you can wait you could order some.

https://www.hydraulicsdirect.com/47305-SAE-080101-Flareless-Compression-Fitting-p/47305.htm

 

[Egon]

Proper rated compression fitting. Hardware stores probably will not carry them.

 

[rly]

I'm heading for a swagelock 1/2" x 1/2" steel union.

 

[Egon]

I'm heading for a swagelock 1/2" x 1/2" steel union.

Just remember there is definite procedure to install/tighten the Swagelock fittings. Definite number of flats or rotation of the wrench.

 

[rly]

Yes, and anti-galling lubricants. I have on hand some copper anti-seize and Permatex PTFE based sealant. Non-copper is recommended, but it says "stainless steel' on the bottle. I'll have to cut out about 1/2" of the steel tubing, and from drawings I think 2 fully inserted tubes only leaves a 1/4" gap inside the fittinging, so I'm hoping the steel tubing will 'give' 1/4". There are several right angle bends in it so I think I'll be OK. I may have to order the part, so I might have a length of hose made up as a temporary bypass. The steel tubing is 1/2" od and a 3/8" drill bit fits in the end fitting so I'm calling the tubing 3/8" ID. I don't know if 3/8" ID hose is sufficient and available, or if I should go up the 1/2" ID hydraulic hose. As it is a low pressure line, I'm also thinking of 1 or 2 braid hose, and not anything stronger since it on the lower pressure side of the hydraulic system.

 

[rly]

Ended up with a Parker Ferulok. Hope I can meet the exacting preparation standards they say these things say require.