Repair to High Pressure line

[rleonard]

I am having some leakage at the high pressure line at the injector fitting.  Inspection of the ferrule attached to the pipe shows some deformation.  It seems that the ferrule does not fit well in the nut and pressure is not applied uniformly when the nut is drawn up, resulting in a leak. 

Has anyone performed repairs to these lines?  I want to machine a new ferrule, carefully cut off the old one, and silver solder the new one on. 

Any reason why this would not work?

Bob

[Tom]

Guy Fawk posted some horrendous pictures of what happens to some ones hand when it is injected with high pressure diesel. It might work, but do you want that hand to be yours for a $3.00 fuel line?

[MacGyver]

Where do you get a $3 fuel line, and why do you trust it to be better quality than a "home made" one?
 I don't know Bob from Adam, but if he's got even mediocre skills I'd trust his work over a *$3 fuel line made in India.* I've already SEEN the quality that comes from India.

Shoot, I'd even trust *my* work over a $3 fuel line made in India!

[Doug]

The line can be made by any Bosch dealer/service center.

eg.
Henniger's Diesel Ltd.
Bosch injection sales and service.
Service dept was amused by the starnge Indian Bosch injector I had but had difficulty making me any lines or repars I may need.

Price never entered into the equation, they charge what they charge and the parts and repairs are Bosch..... 

[Tom]

Where do you get a $3 fuel line, and why do you trust it to be better quality than a "home made" one?
 I don't know Bob from Adam, but if he's got even mediocre skills I'd trust his work over a *$3 fuel line made in India.* I've already SEEN the quality that comes from India.

Shoot, I'd even trust *my* work over a $3 fuel line made in India!

Well I just checked the price list from the last order of parts from India, I was wrong on the price it was $1.35  That was for a 6/1 I'd guess you would need to of them for a twin so make that $2.70 

The main point was leaks and the damage, sever damage they can cause. By the way the best way I've ever seen to test for a high pressure leak was to clamp a piece of paper in a set of vice grips and hold the paper near the suspected leak.

Interestingly the Indian high pressure pipes are the only I've never heard about problems with. Any way the picture of a layed open made quite an impression on me (as well as the guy who owned and almost lost the hand).

[rleonard]

Thanks guys.  I'll call around today and see if I can get a replacement ferrule from a diesel shop.

Bob

[MeanListerGreen]

Thats why I asked if you had a fuel line rupture earlier.  I didn't want to seem like I was judging your skills but high pressure fuel lines are nothing I would want to fool with.  I didn't see the hand pictue but I saw quarter size holes shot in a mans leg when an industrial pressure washer wand got away from him while he was cleaning an oil tank 300 feet in the air.  He had the trigger fastend wide open to keep his hand from cramping up.  He spent some time in the hospital.  IMHO it's just safer and easier to leave that to the diesel shop guys.  You already have the lines made up just take it to the shop and tell them you want one made just like it.  I hate paying other people to do what I am pretty sure I can do but some things I have to realize there are certain safety things that are just out of my realm of expertise.

[rleonard]

I really think that one has to put things in perspective.  There is a major difference in the energy available from a Bryce injection pump dispensing approximately 1 cu mm per cycle @ up to 2200 psi. as compared to a high pressure washer delivering 6 to 10 gallons per minute at up to 5000 psi.   The situation I had with the engine was a drop of diesel that would appear about every minute. 

I have personal experience with water injection from a pressure washer.  A couple of years ago I was washing the truck with my gas powered pressure washer.  My dog Nick, whom appears in a few Lister pictures, thought that this was just another hose to run in front of to cool off.   The water pierced his skin behind his neck and was a very painful injury for him.  Worse yet was the bacteria on the skin is carried below and quickly sets up an infection.  The vet got him all straightened out and he is OK now, but he does stay away from the pressure washer now. 

We're just not comparing apples to apples. 

There are far more accessable dangers with 500 lbs of high speed cast iron flailing in a circle at a rim speed of 46 mph at 650 rpm.

I appreciate the concern and the heads up when dealing with fluids at high pressure.  From my perspective this is a low risk repair and within my abilities to deal with.

This situation does offer the opportunity to call an old friend who runs a diesel shop in a nearby town.  I have not talked to him for a couple of years and it would be good to see him again.   

It's all about the people and the friends we make.

Bob

[Quinnf]

Hey Bob,

Let us know what you find out about that ferrule.  That's been something that's bothered me ever since I got my first engine.  I'd really like to have a few ferrules on hand.  Silver solder should be fine, and good old steel automotive brake line can easily handle the pressure. 

Re: the concerns expressed, I think nobody wants to see anyone get hurt, and there have been a couple of reports of split fuel injection lines.  If that happened while your pinkies were wrapped around the line, you could wish they weren't.  Frankly, I think the chances of a fuel line related injury are pretty remote, given the fuel flow rate on these little engines.  But it never hurts to anticipate where your next injury might come from.

So . . . is your cat deaf yet?

Quinn

[oliver90owner]

The problem is when you have high velocity due to pressure -where there is a leak through a tiny hole.  In a pipe end, the high pressure leak will be directed inside the retaining nut which is not hydraulically sealed.  The fuel flow will actually leak at low veocity from the gap around the pipe, hence generally no problem.  The amount of leakage will seriously affect the engine performance and be obvious before the leak could become dangerous apart from the fire risk.  Now, near an injector nozzle where the high pressure spray is an atomised jet of fuel - that is dangerous as it will go straight through your skin. 

We used to use a 7000psi water lance at enough flow to nearly lift you off the ground when operating it.  It often had a T outlet to spray both ways sideways which was very easy, but when a nozzle became clogged .........  We used to demonstrate the dangers to new operators by cutting up pallets in very short time.  One man wa seriously injured one day when the lance was put down while the pump was still running and the lance suddenly went off.  He was lucky it did not cut through anything more serious than his thigh and shoulder as it snaked around out of control.  He never went back to that job.

Always do that risk assessment before jumping in.  It could save a lot of heartache.

Regards, RAB

[rleonard]

I cut off the leaking ferrule and made this out of stainless;



Trimming the burrs off the line, the hole is rather small;



Checking the fit;



And silversoldering;



The nut makes up nicely to the injector now.  No more leak

Bob

[MacGyver]

Looks like a very nice job of it.
*I* had faith in ya all along. 

[mike90045]

Isn't red hot  a bit high for silver solder ?

[rleonard]

No,
That is right where it needs to be to flow, around 700C

Bob

[rleonard]

This is silver brazing according the the following;

Soldering - The AWS defines soldering as a group of joining processes that produce coalescence of materials by heating them to the soldering temperature and by using a filler metal (solder) having a liquidus not exceeding 840ºF (450ºC), and below the solidus of the base metals.

Brazing - Brazing joins materials by heating them in the presence of a filler metal having a liquidus above 840ºF (450ºC) but below the solidus of the base metal.

Welding - In welding, fusion takes place with melting of both the base metal and usually a filler metal.
 
The flux I use is this:

 

STAY-SILV® Brazing Flux (White)

An all purpose, low temperature flux for use in silver brazing most ferrous and nonferrous metals except aluminum, magnesium and titanium. Stay-Silv® Brazing Flux (White) is an inorganic fluoride type flux molten at 1100ºF and active to a maximum of 1600ºF. Flux residue may be removed with a hot water rinse. Meets Federal Specification OF499C, Type B; AWS Type 3A; AMS 3410F.

Bob