Oil lines

[wshelton]

Hello All,

I have DD 671Ns and am in need of replacing the large oil lines on the engines. There are two large lines, one attached to the top of the oil filter canister, or there about, and the other I am not sure. Both lines attach to what I believe is the oil cooler or pump near the bottom of the engine. Naturally these fittings are going to be next to impossible to unscrew because of the location. These lines are made of rubber I assume, and braided which is now visible and appears rusted. Any idea where to get these replaced or is this easy enough to find a Detroit Diesel dealer and describe what I am looking for?

I am sure I have not done a very good job in describing what I am looking for but any info would be a start.

Thanks,

Will

 

[Bob Bradley]

I would think that any place that makes hydraulic lines could fabricate them for you. I use R.B. Birge in Bridgeport CT for all my lines. http://www.rbbirge.com/
Bob

 

[Genesis]

They're not that hard to get off and most of these engines used reusable fittings on the hose. It's not difficult at all to buy the hose, remove the fittings, cut the new hose to length (a hacksaw will do the job) and put the fittings on the new length. Just make sure you flush the inside of the hose before reinstalling to make sure that gunk doesn't get into the engine (particularly since the hose is wire-reinforced and bits of wire in the oil would be bad!)

You can also pay a hydraulic shop to make 'em up if you want as noted above....

 

[bostonhatteras]

They're not that hard to get off and most of these engines used reusable fittings on the hose. It's not difficult at all to buy the hose, remove the fittings, cut the new hose to length (a hacksaw will do the job) and put the fittings on the new length. Just make sure you flush the inside of the hose before reinstalling to make sure that gunk doesn't get into the engine (particularly since the hose is wire-reinforced and bits of wire in the oil would be bad!)

You can also pay a hydraulic shop to make 'em up if you want as noted above....

Reusable fitting perhaps. Aeroquip fittings are only usable with aeroquip hose and parker lines with parker hose. The hydraulic shop will be able to tell whose fittings they are just by looking. If your not comfortable with your mechanical abilities it may be worth the money to have the shop do it. reusable fittings are pretty tight getting them on. Familiarize yourself with the process before you attempt it.

 

[MikeP]

"Familiarize yourself with the process before you attempt it."

Yep - as noted it is easy enough to do yourself but it is best to read/watch a Utube about the process first as opposed to trying to figure it out if you have never done it. It is not inherently obvious because there are usually some left-hand threads involved.

I have never heard of a fitting wearing out though I suppose it's possible. Normally you just replace the hose itself so you can just go buy/order an appropriate length of hose and cut to fit.

 

[rsmith]

FWIW Parker used to offer a course in hydraulic system design. One of the things they stressed was the fittings were one time use only. Reason being that the male and female flair conform to eachother the first time and reuse would alter that fit and require over torquing of the connection to prevent leaks naturally this could lead to a failure. They recommend when you replace the hose you replace the connection fitting too. Now we all know no one does this including me but it is food for thought.

 

[MikeP]

"They recommend when you replace the hose you replace the connection fitting too. Now we all know no one does this including me but it is food for thought."


Parker has marketing experts like everybody else and I'm sure they rapidly figured out that if they admitted the fittings could be reused and would outlast us all, they wouldn't sell many fittings...

 

[saltshaker]

Don't you need the proper mandrel to put the Aeroquip or Parker fittings on? Given the potential damage if you don't get this right and since you're only changing a few hoses, I would contact MAESCO http://www.maesco.com/ They sell and make up the hoses to your specs. Great guys to deal with and a great source for hose, filters etc.

 

[saltshaker]

FWIW Parker used to offer a course in hydraulic system design. One of the things they stressed was the fittings were one time use only. Reason being that the male and female flair conform to eachother the first time and reuse would alter that fit and require over torquing of the connection to prevent leaks naturally this could lead to a failure. They recommend when you replace the hose you replace the connection fitting too. Now we all know no one does this including me but it is food for thought.

And those fittings aren't cheap. I spent a fortune on them when I replaced all the fuel lines on my 46C. I didn't have anything to reuse since I was replacing all the old copper lines.

 

[Boatsb]

And don't forget there are 2 angles for the flared ends. Get them wrong and they leak.

 

[sgharford]

My 2-bits for reusable fittings - drench the hose ends and fittings in oil prior to assembly (30 wt or whatever you have sitting around) , it will save you sooooo much hard wrenching. I made about 40 oil hoses for both my engines and reused the existing fittings (I have Cummins 903's).

 

[Genesis]

Don't you need the proper mandrel to put the Aeroquip or Parker fittings on? Given the potential damage if you don't get this right and since you're only changing a few hoses, I would contact MAESCO http://www.maesco.com/ They sell and make up the hoses to your specs. Great guys to deal with and a great source for hose, filters etc.

Nope -- no mandrel required for the ones I've run into on Hatts. Two-piece fittings generally do not require a mandrel, three-piece ones generally do (there are probably exceptions, of course.)

I did both engines and gears on my boat in a day; bought the hose and a handful of fittings to replace the ones that were in poor cosmetic shape and had at it. As boat jobs go it was pretty low on the complexity and cussing scales; lubricate with oil and they go together reasonably easily.

 

[Avenger]

A word of caution to those who plan to make their own oil lines:

These are parts from a turbo that failed in less than twenty hours because of a lubrication problem. This is a picture of the turbine. If you look at the tips of the blades and see the little bits of metal sticking up.... the whole blade used to be that tall. They're made of Inconel, it's not soft stuff.

This is the heatshield that sits behind the turbine. It used to be flat all the way across.

The cause of all this is those little bits of rubber in the oil inlet:

It's more than just these pictures. The thrust bearing was cooked, the compressor wheel destroyed the compressor housing with itself. The entire turbo was unsalvageable.

I'm not saying don't try it, just be really careful. I've assembled many a line with no problems. This poor guy destroyed two freshly rebuilt turbochargers by putting "new" oil lines on. Whoever assembled the lines shaved the inside of the hose with the fitting and it ended up in the turbo. The other turbo failed on sea-trial as soon as they pushed the throttles. It was a very expensive set of hoses.

 

[MikeP]

As the old saying goes, "Some people could F$%K up an anvil."

It's a common sense issue - it doesn't matter who made it/where you got it; the new oil line has to be flushed first.

 

[saltshaker]

As the old saying goes, "Some people could F$%K up an anvil."

It's a common sense issue - it doesn't matter who made it/where you got it; the new oil line has to be flushed first.

I don't think that was the issue. Per Scrod's post; "Whoever assembled the lines shaved the inside of the hose with the fitting and it ended up in the turbo."

 

[MikeP]

"I don't think that was the issue. Per Scrod's post; "Whoever assembled the lines shaved the inside of the hose with the fitting and it ended up in the turbo."
"

But flushing the line prior to installation would have eliminated the problem - the fragments of rubber would have been cleared. New lines purchased from a dealer/whoever also need flushing/clearing to ensure there is no assembly junk, insects, whatever. Can't imagine connecting a new oil/fuel/air/brake/whatever line without first ensuring it's clear with solvent/appropriate fluid/compressed air.

 

[Avenger]

The risk is that the peeled pieces may remain attached and not break off until later. The first turbo failed right away, the other ran for several hours before it failed. Did it just have less pieces, or did they break off later? I can't answer that since the first turbo was from the dealer and I didn't get to take it apart.

As long as the assembly is done correctly and there's no damage to the internals it's perfectly safe. I'm just advising caution since not everybody has the same level of mechanical skill.

 

[bostonhatteras]

Another tip on assembling reusable fittings. find and use a large permanently mounted vise. There is a fairly hard bit of wrenching to do before every thing is settled in. Not to muddy the waters here but can push lock fittings be used up to 200 psi? They grip quite well

 

[Genesis]

I would NOT use push-lock fittings for pressure applications (e.g. oil lines) where a failure hoses you HARD, but that's me.

 

[bostonhatteras]

I would NOT use push-lock fittings for pressure applications (e.g. oil lines) where a failure hoses you HARD, but that's me.

I wouldn't either but the specific hose for the push lock stuff goes up to 400 psi like you say, scary. ive been told that the more pressure in the hose, the harder the push locks grip....until they don't! It is an interesting looking fitting