Fixes for the Lee 4/20

[Blanco]

I have had my 4/20 Lee since the first of the year and had really good luck with it.
I got a new MP mould from a group buy and was going to cast up a batch of .40 hp's
all was going good for the first 10 casts, then my luck ran out.
Must have cought a piece of trash in the seat of the valve, and nothing I could do would make it stop. just un-plugged it and let gravity take over. I do have a shallow pan under it and it was low enough on melt that I was ok. So I cleaned it up and started over the next day. Same operation as before only this time I only got about 3~4 casts before the flood came, and the pot was pretty full. Full enough that it spilled out of my catch pan.
So .... Now i am on a mission to fix the whimpy lee pour spout and valve.
I did some searching but didn't see any fixes that looked like what I had in mind. I envision a 1/4 dia valve rod and robust seat with a spring loaded cam over release or heavy weighted handle?

Anyone?

[Beagle333]

Once you get it cleaned out.... a little extra weight on the handle usually solves the problem until something else gets under the valve.

[Blanco]

I decided that it did need a cleaning. Heated it up with a torch and cleaned it with copper chore boy. Cleaned the valve seat and pin as well as possible and used some lapping compound on it as well. Ran close to 300 boolits with nary a drip. Started giving the pin a twist every 10 casts.
Seems to have kicked my drip....

[el34]

Does yours have the flow adjustment screw with the big flat head that fits in a groove at the top of the needle rod? Mine does, and I learned that if I subconsciously pull the handle down at the end of a pour to 'stop it fast' the screw will slip out of the groove. The next time I raise the handle it goes way high and the needle doesn't return all the way down.

I used to routinely tap the rod with something, sometimes the sprue whacker, whatever was handy to re-align.

Then I learned- start the flow by lifting with a just finger under the handle, not grasping it, and simply drop that finger to let it stop. Let the rod/handle drop by gravity, it prevents the screwhead from pulling out of that groove.

[williamwaco]

Sounds like an adjustment problem. I doubt if trash would hold it open that much.

Two things:

1) I use a battery powered screwdriver to spin the rod about two to three seconds every ten minutes or so.

2) I use a large paper clip about half way straightened out to make an L shaped tool. I use this as necessary to force it up into the spout and aggressively clean it out until I can push the rod up from the bottom and let the alloy pour around the paper clip.

REMEMBER THIS: MELTED LEAD FLOWS DOWNHILL. DO NOT ALLOW YOUR HAND TO COME UNDER THE BOTTOM OF THE POT.

Now you know why they call that pot the "Drip-o-matic".

[Blanco]

My rod must be a bit differenter than what you guys have. Mine actually threads into the bracket the handle is on. The more it is screwed in or down the less travel the rod has off of the seat. I just give mine a lil twist.

[imashooter2]

Seems like the easiest solution is to stop putting dirt in your casting pot...

[Blanco]

Seems like the easiest solution is to stop putting lead in my dirt pot...

There... fixed it for you!:bigsmyl2:

[williamwaco]

My rod must be a bit differenter than what you guys have. Mine actually threads into the bracket the handle is on. The more it is screwed in or down the less travel the rod has off of the seat. I just give mine a lil twist.


Mine spins freely in the bracket and has a screwdriver slot on the top. Spinning it helps clean the spout and reduces dripping.

[el34]

Blanco has the latest design where the valve needle rod screws into the lifter bracket. I think I'd like to order those parts and upgrade (?) my pot to eliminate that screwhead-in-the-slot arrangement that occasionally gets separated.

[Magana559]

Lee pots are not all that bad. Make sure the top and bottom pins where the handle slides are clean and slide freely.

As for the leaks....well it was a $60 pot. It happens! just give the plug rod a quick twist.

[Stephen Cohen]

Mine worked for a few casts, then gave trouble. I drained it, cleaned inside and stripped out the valve needle, to my surprise one side had a noticeable flat on it so I lapped it with fine valve past, while held in cordless drill. I no longer have any problems at all with it.

[500MAG]

Seems like the easiest solution is to stop putting dirt in your casting pot...
Funny but true. When I was using a Lee pot I made sure that I only put clean fluxed alloy into it. I hear so many people talking about smelting in their casting pot. Also, I would never run the alloy down too low. Kinda like that old thing about running your gas tank too low and sucking trash. I do the same with my ProMelt.

[Blanco]

I melt my lead in bulk and alloy in my gas fired turkey cooker.
I flux several times and skim until the melt is nice and clean. Then ladle into muffin tins. I still manage to get trash in the lead muffins. In the future I will just clean my 4/20 every so often.

[RayinNH]

Blanco has the latest design where the valve needle rod screws into the lifter bracket. I think I'd like to order those parts and upgrade (?) my pot to eliminate that screwhead-in-the-slot arrangement that occasionally gets separated.
If you take thin wire and make a few wraps around the screw threads and valve pin it helps a lot to keep the two together.

[Gunor]

I only noticed one weight suggestion - I put 3 large flat washers behind the knob...

Geoff

[el34]

If you take thin wire and make a few wraps around the screw threads and valve pin it helps a lot to keep the two together.
Thanks Ray. I think the tension would matter but would probably be easy to get it right. Gonna try that next casting session.

[el34]

I only noticed one weight suggestion - I put 3 large flat washers behind the knob...

Geoff

I'm waiting for someone to make a lead handle. Maybe powdercoat it.

[jmort]

Someone posted a picture of a lead ingot/handle recently on a 4-20

[el34]

Someone posted a picture of a lead ingot/handle recently on a 4-20

Dangit. Every time I get a good idea somebody steals it before I had it.

[dikman]

If you look at the design, I reckon you'd be better off putting any additional weight on the end of the metering rod (where the adjustment is). This will keep the weight pushing straight down on the valve, which is where you want it.

[Ausglock]

I put a compression spring under the adjusting screw to stop it from self adjusting while in use. Works great.

[dikman]

I went one better - I rebuilt mine using the same style handle as the RCBS ProMelt.:razz:. Now it works like it should!

[el34]

I went one better - I rebuilt mine using the same style handle as the RCBS ProMelt.:razz:. Now it works like it should!

Sounds intriguing- got pics? With a little narration?

[multigunner76]

I have the older style Lee 4/20 Same thing happened last night. Mabe cast ten rounds with a 6 cavity and then the flood came. Mine has no adjustment andwhere on it. I gave up and broke out the camp stove. Well it went up in flames. Literally. Guess it had a gas leak and flamed up. I guess its time to look for a new pot.

[el34]

I have the older style Lee 4/20 Same thing happened last night. Mabe cast ten rounds with a 6 cavity and then the flood came. Mine has no adjustment andwhere on it. I gave up and broke out the camp stove. Well it went up in flames. Literally. Guess it had a gas leak and flamed up. I guess its time to look for a new pot.


Can you post a pic of your pot?

[dikman]

http://castboolits.gunloads.com/showthread.php?241314-My-%28new%29-Lee-pot-mods

This good enough, el?

[el34]

http://castboolits.gunloads.com/showthread.php?241314-My-%28new%29-Lee-pot-mods

This good enough, el?

Well holy poop, that's great! I was out for a few months and completely missed it. Thanks, lots of good ideas there.