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**Wotname** · 04-09-2019, 20:01

It's been awhile since I last updated this thread and I'm sad to report that the old injector lines haven't repaired themselves while sitting unattended for the last 9 months.

However I have found out it hard (impossible?) to get weld/braze on nipples in Australia. The freight costs prohibit getting them ex USA. I am chasing up some from info the UK and hopefully the pricing will be attractive.

The local injector shop can supply the steel line (6mm x 2mm) although he tells me from his experience the quality is less than ideal (Asian supplier).

To briefly recap the costs here (per set):
New from Yanmar - ~$250
Used (various condition) - ~$150 (or more)
Custom made with cold forged nipples - ~$200

So the project is not dead in the water - yet!

model 10 · 06-09-2019, 13:53

Can you chuck the old ends up in a lathe and remove the tube? Or make a new end. I am a piss poor machinist, but I could make one without much trouble.

Compass790 · 06-09-2019, 14:21

Quote:

Originally Posted by Ecos

Can you chuck the old ends up in a lathe and remove the tube? Or make a new end. I am a piss poor machinist, but I could make one without much trouble.

Yea another vote for that. I did suggest something similar in PM but I have an ulterior motive

**Wotname** · 06-09-2019, 18:09

Quote:

Originally Posted by Ecos

Can you chuck the old ends up in a lathe and remove the tube? Or make a new end. I am a piss poor machinist, but I could make one without much trouble.

Yes, removing the tube from the nipple in a lathe is a consideration and doable.

Unfortunately I now only have three good ends - I destroyed one when I thought they were brazed on when it fact they were forged nipples on the steel tube. No amount of heat would un-braze a forged end but I applied enough heat to completely deform the forged end!!!

This what happens when the uninformed (me) takes advice from the internet but doesn't know enough to know when to stop. Still, it's all part of the learning process and I now know more about injector lines than I ever thought I would.

Machining a completely new one might be above my pay grade bit and could be a wild goose chase but never say never.

Does anyone have any idea of where to get dimensions of the end - in particular the angles? I can measure the diameters of the old ones but I don't think I can the angles accurate enough to reproduce them.

Compass790 · 07-09-2019, 14:50

Dunno where you would get dimensions apart from dusty yanmar files but can you put the nipples in the lathe & use the DTI on the toolpost to get the angle?
I'm a complete machinist newbie , just my guess. Might well be harder than I imagine as I dont know what yours are like but (from maybe hazy memory ) our nipple ends might be rounded rather than a straight taper.

**Wotname** · 07-09-2019, 18:05

Quote:

Originally Posted by Compass790

Dunno where you would get dimensions apart from dusty yanmar files but can you put the nipples in the lathe & use the DTI on the toolpost to get the angle?
I'm a complete machinist newbie , just my guess. Might well be harder than I imagine as I dont know what yours are like but (from maybe hazy memory ) our nipple ends might be rounded rather than a straight taper.

Well I must even less of a machinist than you - I know what a tool post is but what's DTI - and is it a good thing or bad thing

A picture is worth a thousand words so here are two thousand.
FWIW, the tube is 6mm x 2mm, the OD of the forged nipple is a bit over 9mm but a bit under 3/8" and the OD of the "other part" (ferrule???) is about 11.5mm.

Does anyone know if this a common size (apart from used lots in old Yanmars) and if so, what is it called?

wsmurdoch · 07-09-2019, 19:13

Similar but with a female nut...

Pulling Injection Lines – Fair Valley Performance

**Wotname** · 07-09-2019, 23:59

^^ thanks, interesting and FWIW, the other end of my lines have a female nut.

RaymondR · 08-09-2019, 03:08

Quote:

Originally Posted by Wotname

Well I must even less of a machinist than you - I know what a tool post is but what's DTI - and is it a good thing or bad thing

A picture is worth a thousand words so here are two thousand.
FWIW, the tube is 6mm x 2mm, the OD of the forged nipple is a bit over 9mm but a bit under 3/8" and the OD of the "other part" (ferrule???) is about 11.5mm.

Does anyone know if this a common size (apart from used lots in old Yanmars) and if so, what is it called?

The nuts would be aesy enough to machine if you can find steel plugs and centre drill them.

The ferules are re-usable.

The ends on the tubes could be built up with oxy welding and machined back to the correct form with the tubes straight and then the tubes bent as required.

Piece of cake.

**Wotname** · 08-09-2019, 05:25

Quote:

Originally Posted by RaymondR

The nuts would be aesy enough to machine if you can find steel plugs and centre drill them.

The ferules are re-usable.

The ends on the tubes could be built up with oxy welding and machined back to the correct form with the tubes straight and then the tubes bent as required.

Piece of cake.

Existing nuts are re-useable.
3 of the 4 ferrules are re-useable and I can make the fourth.

Any suggestions on how to determine what exactly is the correct form ?

RaymondR · 08-09-2019, 11:05

I have seen a shadowgraph device used for thread forms. A bright light is shone from one side of the object of interest and it's shadow measures on a plate on the other side but I would try cutting one of the ends off and chucking it up and then getting the tool holder to the correct angle with a dial gauge.

How extensive are the corroded places on the old tubes? If they are only corroded where the clamps were, machining insert sleeves out of round section and TIG welding them may be a better proposition.

**Wotname** · 08-09-2019, 18:41

Quote:

Originally Posted by RaymondR

I have seen a shadowgraph device used for thread forms. A bright light is shone from one side of the object of interest and it's shadow measures on a plate on the other side but I would try cutting one of the ends off and chucking it up and then getting the tool holder to the correct angle with a dial gauge.

How extensive are the corroded places on the old tubes? If they are only corroded where the clamps were, machining insert sleeves out of round section and TIG welding them may be a better proposition.

Yes, I am considering just replacing the corroded section on one of the lines; unfortunately as posted earlier, I have destroyed one of the existing ends so I will have to sort that regardless.

Turning an end is getting closer now I know what the DTI is

model 10 · 09-09-2019, 14:43

How are you going to bend a new line? If a line on my Perkins is not perfect, you can't get a nut started. If you weld it up, it won't line up either.

**Wotname** · 09-09-2019, 16:40

Quote:

Originally Posted by Ecos

How are you going to bend a new line? ........

That is a good question and the short answer - I dunno!

The long answer is:

The plan is use my reasonably heavy duty 6mm tube bender ( it's good for up to 10mm tube - with separate dies) but I haven't used it for injector line yet so it's going to be suck it and see approach.

I get that bending 6 x 2 mm tube is essentially bending 6 mm rod so it will be a test for sure. I haven't tried bending the existing lines as I want to keep them as the model for the new ones.

If the bender isn't man enough for the job, I will probably make up something with rollers and maybe hardwood formers - will cross that bridge when I get to it.