Diesel engine : Kromhout Gardner 4LW 1940

[minh-thanh]

Hard to tell from the picture but is the lapping tool split?

I'm a bit late to reply, sorry.

No, it's not necessary
I sharpened it to the angle of the needle and sharpened it with a file - making a place for the abrasive to stay - it's made of steel
I tried with aluminum, but it's too hard to do and it wears out too fast

 

[minh-thanh]

Hi All !
An update

I've done the fuel pump cylinder but haven't lap yet
With some testing, I found a pump cylinder length of about 8 to 10 mm to be fine - because the plunger stroke is very small - about 1 mm, but I wanted the best I could so I made it almost 2 times longer.
The engine only needs 4 but I did 5 and I will choose the best 4 for the engine and the other 1 for the injector testing.
With this 4-cylinder engine, I try to equalize the amount of fuel for each engine cylinder so I have to make 4 cylinders of the fuel pump which must be of the same diameter.

Although I have some experience with small diameters, But before I lapping , I need to redefine a few things, so I made several cylinders out of brass, steel and different lengths. for test

Cylinder and plunger for test

lapping this small diameter cylinder probably only have 2 options: buy or make it yourself
Lapping it is a challenge
Must be remove all scratches caused by drilling or reaming and to ensure it is relatively straight throughout the lapping process.
With purchased or homemade tools, they only have 2 parts in contact with the cylinder - they actually don't make perfect contact with the cylinder and it can give a lot of shape to the cylinder - so lapping takes very careful and meticulous

 

[minh-thanh]

Hi All !
An update with few mistakes

I make some washers for the cylinders, they are made from mosquito spray bottles and soda cans

And :

 

[minh-thanh]

Hi All !
An update :
The lapping for the pump cylinders I have only done a little bit,
I will do it little by little
I just finished the injectors and tested with compressed air, they are airtight

 

[minh-thanh]

Hi All !
An update :
Fuel pump :
Some parts of the fuel pump

 

[minh-thanh]

Hi All !
An update :
Some parts of the ball valve block
I changed when I machined it

 

[Roger B]

Excellent Progress

 

[minh-thanh]

Hi All !

An update :

Checked everything ball valve and cylinder + plunger : It's ok
Next : the block for the pump camshaft

 

[minh-thanh]

Hi All !
An update
It seems to be a mistake, maybe I should choose the 2 cylinders
But for now there is no choice but to continue

 

[stevehuckss396]

Consider this one a practice engine

 

[Scott_M]

What was your mistake ? That camshaft looks really nice !

Scott

 

[minh-thanh]

What was your mistake ?

Scott

The first camshaft, the 3rd cam lobe got the wrong angle and a few other parts I had to redo
I should have chosen a 2 cylinder engine, with fewer cylinders less parts.... anyway complaining is pointless.
Must go on .

 

[minh-thanh]

Hi All !
An update

I haven't finished the fuel pump yet, I will continue with it later.
Image of the crankshaft more than a month ago

Because the stroke is too long and have time to learn more about the cause of the shaft fracture....
So I borrowed my brother's machine to do it - I did it very slowly, as carefully as possible, as well as reduce stress..when i machining it
And :

And camshaft :

 

[minh-thanh]

Hi All !
An update
I drilled 4 holes for the fuel pump - They are really hard to locate and drill , with 1 hole drilled in the wrong place so I made another piece of aluminum and drilled it again , I drilled from drill bit 3 -> 3.5 -> 4 and finally 5mm and make thread 6x1 mm

I have to make an extra shaft similar to the crankshaft and camshaft to locate......

 

[minh-thanh]

Hi All !
An update
I made brass bearing for crankshaft and camshaft
I didn't solder the 2 pieces together, I drilled and joined them with dowels

 

[peterl95124]

Minh, thanks for sharing, I've never soldered bearing halves together either, I just put the two pieces in a 4-jaw chuck and machine away. if the parts stick out beyond the chuck and I'm worried about a drill bending the halves apart (happens with crappy bronze, AKA gunmetal) then a collar with a setscrew will hold them together or a lathe dog or any sort of makeshift clamp.

 

[minh-thanh]

Hi Peter !

When I process it I usually do it in order
EX : If there is ID 10mm and OD 12mm
1- drill holes 3 or 3.5 mm
2- drill hole 6
3 - drill holes 8 and drill holes 9 mm
4 - Turning outside diameter approx. 13 or 13.5mm
5- Turn inside diameter up to 9.8 or 9.9 mm
6- Turn the outside diameter to the final size
7- The final step is to reaming or lapping the ID to a size fit for the shaft
If the ID has a suitable diameter for ID turning, then I drill 3 or 3.5 mm and then turn to a 9mm hole and do the rest of the steps.
Sharp drills and sharp turning tools .

 

[minh-thanh]

Hi All !
An update
I made the part for flywheel to assemble the crankshaft, camshaft, gears, block ... I need to put them together to make sure everything " fits " together.

Everything's fine, I'll get it fully assembled then I can focus on the rest of the engine.

 

[minh-thanh]

Hi All !
An update
I have aligned and assembled the parts of engine
This engine I will do the lubricating oil pump , but it will be the last item after the engine has run ( I hope ... will run )
I'm making valves for the engine

 

[minh-thanh]

Hi All !

How I make a valve like a flat head screw
- Drill holes 1.6 mm deep 1 mm
- Use Screwdriver Bits + hammer + base - as shown in the picture
I like it in screw form because it's easy for me when lapping