Micro 12VDC Generator with a Cox .049 Sure Start Diesel Engine

robot797 wrote:you sir are one of the best people i know

and for that starting problems
i think that was becaus of leftover fuel in the engine

and for the crank
if i were to heat it untill it glowed red and after that dipping it in oil that would mean it got harder
i now have alterd the structure of the metal to become a bit softer

my thoughts tell me that if the crank it to hard it breaks from the diesel kickback
if it is softer it absorbs the blows and breaks less

Many people on the internet say Nitro cranks are week. However, for your application you can use a nitro crank with lowered compression and the Fuel Needle Valve positioned to a very low setting, just to start. Then you must ensure you always run rich and the compression is not strongly tightened. This way you will reduce tension to the crank. Ensure no flooding nor too much fuel when starting with the motor and always air thus you may wish to have the AirValve, Trottle, not more closed than 25%closed,75%open.

As far as hardening and softening is concerned, slow tempering down from hot will help you get rid from previous stress and relaxed the bent metal. I do not think the metal will soften.

robot797 wrote:i did follow the guid in the description of this video
https://www.youtube.com/watch?v=VC19dElwAVA

he seemed like a guy who knows his stuff

that is why i decided to temper one crank (i have one or 2 special cranks more)

No problems. Everything is OK when works.

Made the propeller bracket to be able to start with an electric drill. This looks like a double propeller which looks like a biplane's wing. Two propellers, 4cm apart from each other. Another bracket is connected to the drill to rotate one of the propellers while the other is connected to the propeller screw. This way, the drill can safely rotate the engine, far away from the belt.

robot797 wrote:i forgot to add this on my picture post
http://en.wikipedia.org/wiki/Tempering_%28metallurgy%29

True. Should work. Not sure to what amount the hardness would be removed but sounds promising.

robot797 wrote:i did follow the guid in the description of this video
https://www.youtube.com/watch?v=VC19dElwAVA

he seemed like a guy who knows his stuff

that is why i decided to temper one crank (i have one or 2 special cranks more)

Works fantastic. I am also impressed how stable the fuel needle valve of the engine is. The one I have is not as stable. Looks like this engine has a great spring on the needle valve and, probably, a higher density of the needle and intake threads.

The engine performs excellently with a big propeller. So, do whatever this person says and you are OK.

robot797 wrote:i guess the metal lost enough stress to work
if not will heat another one hotter and longer

OK. The person on YouTube said 2 hours at 250C. Should be OK.

For the hand crank : do not spend more than 15 minutes. Not a big deal.

StevenStanleyBayes wrote:

robot797 wrote:i guess the metal lost enough stress to work
if not will heat another one hotter and longer

OK. The person on YouTube said 2 hours at 250C. Should be OK.

For the hand crank : do not spend more than 15 minutes. Not a big deal.

Also, while waiting for the conversion, you can build the second generator and run on Nitro. Yhen, in case you want, you can convert the engine to diesel.

robot797 wrote:i am already working on it

it will be a smaller unit that may fit inside an aluminium profile
but i am still looking for the right size

You are very good st selecting the right dynamo for the job. Can you find a dynamo which has real bearings and not just pieces of metal. Can you also look for a dynamo which is powerful and reaches 12V at 0 load at 2000 or 3000 RPM but has a light rotor and does not put mechanical resistance to the engine when unloaded. I know this is controversial.

Also look for high efficiency at 12V, 2 to 4A, 4000 to 6000 RPM.

Posting your present and future dynamos is a great help.

Your present design is OK. In case you can put gears which can be selected before start and a mechanically controllable clutch, you will be a genius.

I do not thing you will be able to find these but try.

I see you both running brushed can motors for your generators. Have either of you considered using a brushless motor with a bridge rectifier to get a much more efficient generator? Should give a 20 or 30% boost in electrical output for the same mechanical input, if chosen correctly...

J

JasonB wrote:I see you both running brushed can motors for your generators.  Have either of you considered using a brushless motor with a bridge rectifier to get a much more efficient generator?  Should give a 20 or 30% boost in electrical output for the same mechanical input, if chosen correctly...

J

And will probably put a lower rotational resistance at 0 electrical load as they may be lighter.

I have initially chosen YAF 54 alternaror which will get 1.4 V lower voltage after the rectifier. Worth. These are tiny and can go to 50W and more.

Very expensive after shipping charges. I n case anyone can find them for a reasonable price and free shipping, I would get one. I am prepared to spend around $30 for one. I doubt they have real bearings, though.

One way or another, your post is very important. I am happy you shined the light on efficiency as I was not sure bruushless alternators are more efficient.

In case anyone find anything else, please post. I have only been able to find YAF 54 and at ridiculous prices.

robot797 wrote:i am already working on it

it will be a smaller unit that may fit inside an aluminium profile
but i am still looking for the right size

In case you want a grip on the flywheel, you can get an internal bicycle tube from the bike shop near you for free, old, used and broken. Then, cut the tube in slices and superglue around the two sides of the outer of the flywheel.

BEFORE YOU READ THE REST : I cannot believe the crankshaft pin got broken because I have previously abused the same crankshaft ( with a different piston ) and everything was perfectly OK. This piston may have had a lot of friction with the cylinder. Unlikely. Anyway, I suspect the pin broke when I tested the electric drill start WITHOUT ANY FUEL, THUS WITHOUT ANY OIL, rotated to the maximal electric drill RPM ( 2500 ). This may have happened now too. There was no any fuel in the cylinder because of a full clog of the fuel intake. Those of you who think these cranks brake are not right. As I have said : I have been abusing this crank with or without an electric drill tremendously and the crank has been perfect. I have run the crank with a powerful electric drill flooded with fuel at full compression. No problems. I cannot explain how I have been able to break the pin.

The electric drill start broke the crankshaft pin without any fuel, thus, without any oil in the cylinder. This was surprising because I had been using electric drill a lot and very abusively without any problem. In addition, the fuel line and intake was so much clogged so I was unable to blow through the fuel line. When I sucked, a huge chunk of dirt came out and I had to spit the dirt out. Now, I can freely blow through the unclogged intake. Must check the rest, i. e. whether the path from the intake to the crankcase is OK. One way to do so is by screwing the Fuel Needle Valve fully in and blowing through the crankcase.

The positive thing is the instruction manual of how to replace the crankshaft. Here is a Cox document on the topic : http://coxengines.ca/files/carb%20body.pdf

I think what the document means to say is to disassemble everything until I hold the crankcase with the crankshaft inside in hands. Then, I am supposed to screw the propeller screw in ( without anything on the propeller screw ) and tap on the screw until the crankshaft plate separates.

I think the crankshaft plate is monolithic with the shaft. I think the shaft has the propeller screw thread threaded into the shaft. I think the shaft is press fit into the red nut which red nut is monolithic with a tiny pipe which goes towards the crankcase and very near to the crankcase. This way, the nut and the crankcase are separated. The piston rotates the crank plate which is hard connected ( monolithic ) with the propeller shaft which rotates the propeller screw. In order to stop the fuel from leaking as well as for assembly of other parts ( spring nut, etcetera ), there is a red nut with a hard connected tiny pipe ( housing ). Thus, pipe ( housing ) of the red nut goes very near the crankcase pipe ( housing ) which houses the shaft ( less than or around 1mm near ).

Looks like the red nut is press fit to the crankshaft and hence tapping on the propeller screw is necessary.

Once the crankshaft comes out of the red nut and pipe ( collet ), then the question is just to remove the loose crankshaft and plate out of the crankcase and hence some plastic prying tools may come handy so the crankcase is not damaged by metal ones or, in case of metal nose pliers are used, they have to be used correctly.

Thus, the main trick is to tap the propeller screw gently to remove the red nut and pipe ( collet ) from the crankshaft and then the crankshaft is loose and slightly awkward to come out from the crankcase cylinder hole or from the backplate hole.

Again :

When I say crankshaft plate, I mean this triangular ( flywheel type ) piece which has the crank pin to which the piston rod attaches : http://coxengines.ca/cox-.049-killer-bee-diesel-crank.html

When you say drive plate, you mean the hexagonal red nut with a tiny housing which press fits to the teeth of the crankshaft which teeth are positioned over the propeller screw thread inside the crankshaft.

Look at the lower picture of http://coxengines.ca/cox-.049-killer-bee-diesel-crank.html :

From left to right : crankshaft piston rod attachment pin, crankshaft almost triangular flywheel type plate, crankshaft, crankshaft teeth for the hexagonal nut ( a. k. a. drive plate ).

So, tapping will move the teeth of the crankshaft away from the teeth of the red hexagonal nut ( plate ).

Once the crankshaft is pried out of the teeth of the hexagonal drive nut, the crankshaft will fall off of the backplate hole of the crankcase.

http://coxengines.ca/cox-.049-killer-bee-diesel-crank.html

I have just tried to get 2 new crankshafts from Cox but they are out of stock.

Does anyone have any? I can either purchase this from whoever has or get one now to continue the tests and return a brand new one directly mailed from Cox. Cash fro Crank or Old for New.

Does anyone know where I may be able to get some? I have not yet tried eBay.

roddie wrote:Hi Steven, It's unfortunate that your crankpin broke. It may have been weakened at some point previously.. and finally snapped.

When you install a new one, consider installing a thrust-washer between the case and the drive-plate. It's difficult when using your electric drill as a starter; to know how much pressure you're applying. The friction (heat) of the drive-plate on the case will wear-out the two surfaces prematurely. I always put a drop or two of oil behind the drive-plate prior to using an electric starter.. and I'm very careful to only apply enough inward-force to turn the crankshaft. I do this in short "bursts" of a fraction of a second. Any longer than that is going to do damage eventually.. if not immediately.

Thrust-washers are used by boat modelers.. because their "water-props" exert an inward force through the drive-shaft against the drive-plate on their engines.. unlike an airscrew; which pulls outward.

This is a very smart idea. However, will not the thrust washer wear the crankcase shaft housing and or the drive plate crankshaft housing? I would understand the point in case there is a way to put the thrust washer in such a way, so the thrust washer is mounted on the crankcase and does not move. This way, the drive plate would move against the thrust washer and the only thing which would wear is the inexpensive drive plate. I do not know whether this is what you mean but, in case so, do you know any specific thrust washers which would fit? Please, explain.

The information of the inward force of the water propellers is very useful, thank you.

I do not plan to use an electric drill as a standard way of starting the engine but this way is a good way for testing. Thus, I would be happy to put some protection washer on the crankcase. I am not sure whether I can get the exact size. I would imagine a good washer would be a washer with housing ( pipe ). The housing goes over the crankcase and keeps the washer stable and not movable. The drive plate moves against the washer and may touch the washer but will not touch the crankcase housing.

The inward pushing of the drill does create high temperature of the drive plate and crankcase point. I am not sure whether this temperature can proliferate through to the crank pin.

Metal fatigue, however, is a consideration and may have lead to the breaking.

There is another explanation but I doubt to be true : the new Castor Oil is a medical Castor Oil which has much higher viscosity than the normal Castor Oil and is very gluey. The lack of fuel and just old Castor Oil in the cylinder may have created a drag.

StevenStanleyBayes wrote:

roddie wrote:Hi Steven, It's unfortunate that your crankpin broke. It may have been weakened at some point previously.. and finally snapped.

When you install a new one, consider installing a thrust-washer between the case and the drive-plate. It's difficult when using your electric drill as a starter; to know how much pressure you're applying. The friction (heat) of the drive-plate on the case will wear-out the two surfaces prematurely. I always put a drop or two of oil behind the drive-plate prior to using an electric starter.. and I'm very careful to only apply enough inward-force to turn the crankshaft. I do this in short "bursts" of a fraction of a second. Any longer than that is going to do damage eventually.. if not immediately.

Thrust-washers are used by boat modelers.. because their "water-props" exert an inward force through the drive-shaft against the drive-plate on their engines.. unlike an airscrew; which pulls outward.

This is a very smart idea. However, will not the thrust washer wear the crankcase shaft housing and or the drive plate crankshaft housing? I would understand the point in case there is a way to put the thrust washer in such a way, so the thrust washer is mounted on the crankcase and does not move. This way, the drive plate would move against the thrust washer and the only thing which would wear is the inexpensive drive plate. I do not know whether this is what you mean but, in case so, do you know any specific thrust washers which would fit? Please, explain.

The information of the inward force of the water propellers is very useful, thank you.

I do not plan to use an electric drill as a standard way of starting the engine but this way is a good way for testing. Thus, I would be happy to put some protection washer on the crankcase. I am not sure whether I can get the exact size. I would imagine a good washer would be a washer with housing ( pipe ). The housing goes over the crankcase and keeps the washer stable and not movable. The drive plate moves against the washer and may touch the washer but will not touch the crankcase housing.

The inward pushing of the drill does create high temperature of the drive plate and crankcase point. I am not sure whether this temperature can proliferate through to the crank pin.

Metal fatigue, however, is a consideration and may have lead to the breaking.

There is another explanation but I doubt to be true : the new Castor Oil is a medical Castor Oil which has much higher viscosity than the normal Castor Oil and is very gluey. The lack of fuel and just old Castor Oil in the cylinder may have created a drag.

Also, a standard thrust washer may do in case made of much softer metals or plastics to prevent wear of the other components. I may try to find some.

StevenStanleyBayes wrote:

StevenStanleyBayes wrote:

roddie wrote:Hi Steven, It's unfortunate that your crankpin broke. It may have been weakened at some point previously.. and finally snapped.

When you install a new one, consider installing a thrust-washer between the case and the drive-plate. It's difficult when using your electric drill as a starter; to know how much pressure you're applying. The friction (heat) of the drive-plate on the case will wear-out the two surfaces prematurely. I always put a drop or two of oil behind the drive-plate prior to using an electric starter.. and I'm very careful to only apply enough inward-force to turn the crankshaft. I do this in short "bursts" of a fraction of a second. Any longer than that is going to do damage eventually.. if not immediately.

Thrust-washers are used by boat modelers.. because their "water-props" exert an inward force through the drive-shaft against the drive-plate on their engines.. unlike an airscrew; which pulls outward.

This is a very smart idea. However, will not the thrust washer wear the crankcase shaft housing and or the drive plate crankshaft housing? I would understand the point in case there is a way to put the thrust washer in such a way, so the thrust washer is mounted on the crankcase and does not move. This way, the drive plate would move against the thrust washer and the only thing which would wear is the inexpensive drive plate. I do not know whether this is what you mean but, in case so, do you know any specific thrust washers which would fit? Please, explain.

The information of the inward force of the water propellers is very useful, thank you.

I do not plan to use an electric drill as a standard way of starting the engine but this way is a good way for testing. Thus, I would be happy to put some protection washer on the crankcase. I am not sure whether I can get the exact size. I would imagine a good washer would be a washer with housing ( pipe ). The housing goes over the crankcase and keeps the washer stable and not movable. The drive plate moves against the washer and may touch the washer but will not touch the crankcase housing.

The inward pushing of the drill does create high temperature of the drive plate and crankcase point. I am not sure whether this temperature can proliferate through to the crank pin.

Metal fatigue, however, is a consideration and may have lead to the breaking.

There is another explanation but I doubt to be true : the new Castor Oil is a medical Castor Oil which has much higher viscosity than the normal Castor Oil and is very gluey. The lack of fuel and just old Castor Oil in the cylinder may have created a drag.

Also, a standard thrust washer may do in case made of much softer metals or plastics to prevent wear of the other components. I may try to find some.

The only useful thing I can think of is a very thin and very SOFT Aluminium thrust washer. The crankcase is made of Aluminium, hopefully, hard alloy. I do have 1mm Aluminium but this is too thick, I think. So, to find soft Aluminium washer with the exact size of hole may be a challenge. I can manufacture one but I am not sure whether 1mm would be good enough. I can, however, insert the hexagonal drive plate not all the way through on the crankshaft and this would give more room for the washer. I cannot see much of a point to put a washer of hard metal except the washer would not be as sharp as the drive plate and would not wear the crankcase as much.

A thrust washer sounds like a good idea.