Lister cast piston

[HobbyNutParticipant @hobbynut]

The "DUX" injector is a simple thing. it has no moving parts, and is basically a valve in a body. The valve face is lapped into the seat, and then a "scratch" is made across the valve surface to create a "leak". This scratch becomes the orifice. Because of its minute size, it apparently does not affect the compression any appreciable amount. I have made this from Silver steel, threaded it into the head, and the valve is Silver steel with a .188" dia head, a 2mm dia stem and 2mm-.4 thread at the top. The nut is 3/16 hex.

The theory of operation is that the fuel makes its way down the stem and out the scratch at each pump stroke. The valve body is drilled 2.1mm dia. and I filed 2 small slots into the u/s of the nut.

Pics soon.

[HobbyNutParticipant @hobbynut]

The pics I just uploaded.

[HobbyNutParticipant @hobbynut]

Tested the pump tonight….it puts out 344Kpa, 50psi, 3.44Bar. Is it enough? only time will tell..

[EnnechParticipant @ennech]

I think you will need a bit more than that Hobby. The full size engine works at 90 bars (1305psi)

[HobbyNutParticipant @hobbynut]

Posted by Ennech on 18/09/2013 11:14:42:

I think you will need a bit more than that Hobby. The full size engine works at 90 bars (1305psi)

I think I will too…..But more testing, fitting, modifying etc will get it working!! I hope.

Pat.

[Larry Coleman 1Participant @larrycoleman1]

Patrick

Why not try and machine a press in skirt and make it so you can put in some steel rivets because it will vary in operation temperature so you will have to put some rivets. Now I don't think you will need all the skirt inside dia for conrod clearance. maybe make the skirt from bronze.

Just a suggestion and welcome to the prangs dings & scratches club. If you haven't stuffed up you haven 't made much.

Larry

[martin perman 1Participant @martinperman1]

Gentlemen,

Sorry if i'm teaching grannies but when I worked at Lucas CAV it wasnt unusual to send workers to the local hospital because when testing the fuel injectors the operators would accidentally inject themselves which would cause very bad swelling and pain, if you must wipe the nozzle use a brush.

Martin P

[Ian S CParticipant @iansc]

Martin, you can have the same through the skin oil injection problem with leaking hydraulic hoses.

Ian S C

[Larry Coleman 1Participant @larrycoleman1]

Ian & Martin

The subject you have raised is very important and is worth mentioning. Some of us are very aware of the dangers of working around hydraulic hoses & diesel injectors. But some are not !!!!!!! The thing that was always pounded in to me when working in those environments was eye protection. One thing not mentioned was super heated steam leaks because super heated steam is invisible and apart from the noise of a leak it is still very dangerous.

Well done lads it is the old men of the industries obligation to pass on their knowledge.

That brings back memories of when I worked for Coca Cola in Cairns we had very big flood cooling Ammonia plant and tucked away in the corner of the compressor room was a cylinder of chlorine gas for the water purification plant. This gas was lethal and if you had a leak and you breathed it you would be unconscious very quickly. My apprentice went in to check an ammonia compressor and I went to get some tools. When I come back he was unconscious on the floor so I grabbed his arms and dragged him outside on the footpath where he eventually regained consciousness. That is how easy it was to get killed so from then on we always worked in that room with the second person standing at the door in visible line of sight. Buy the way ammonia leaks always stay at ground level and you feel it at the back of your knees first and if its deep it stings the crown jewels' and I mean stings.

It is never unreasonable to pass on that sort of knowledge. I commend you.

Larry

 

Edited By Larry Coleman 1 on 04/01/2015 13:17:47

[Larry Coleman 1Participant @larrycoleman1]

Here is a small truck I put together with a cat V12 with 3,600hp engine

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