Meheen filler problems

[grs]

I posted a question on the 'Meheen users unite' thread but figured I'd create a new one for my bottling problems (nightmares is more like it). I'm looking for some help with what seems to be a foaming problem. I've got an old 1992 safecracker model that has been retrofitted with a new controller and modified for the Canadian 341 mL bottle.

Earlier this summer I started having problems with the fill sensitivity on the machine. About 1/3 to 1/2 of the way through the brite tank the filler would become 'super sensitive', sensing beer right after the fill head dropped and indexing an empty row. The solution was to drop the fill sensitivity to roughly 60% of what it was and, no problem, filling carried on just fine - until today. After 6 hours and almost twice as many crowns (each empty row gets capped) I was done. The things I noticed:

-Same thing with getting 1/2 way through the brite tank then having to adjust the fill sensitivity, however after this:
-It seemed that beer was getting up the off gas tube but not out the hoses, so that when the next row was indexed and the bottle pressured up to the beer pressure the beer in the off gas tube would be sprayed all over the stainless off gas tube, causing a 'beer present' situation the moment the fill valve opened, indexing to the next row.
-If the sensitivity was dropped to where the empty rows wouldn't index, the beer would fill just fine but I'd lose a lot out the off gas hose and the moment the fill heads lifted out the bottles would foam over like crazy, regardless of the low pressure setting. This resulted in 5 cases of low fills which I'm sure my free bottling help loved but I didn't.

That was my afternoon, trying to find a balance between foam overs that resulted in low fills and the hassle of uncapping every third row and putting the empty bottles back on the infeed ramp. I thought I had the solution when I found the snift pinch valve tubing had a crack in it but nada. The beer just seemed like foaming like crazy. Just to note, I haven't changed the carbonation levels at all from previous batches and there wasn't a lot of foam on the surface of the beer to throw off the fill sensor.

After this long winded explanation I'm looking for some help if anyone's encountered a similar situation. At this point I don't know if it's the filler, the carbonation of the beer, the summer heat, or what. I plan on taking the Meheen apart, replacing every bit of tubing on it but I don't know if that will solve anything (it needs to be done anyway). On the other Meheen thread Linus mentioned that there might be springs broken that are used for the fill sensor and I'll investigate that too. The only other thing I noticed was that the CO2 pinch valve didn't close all the way which resulted in a bit of CO2 bleeding through the line. I tried adjusting this part way through but it didn't do anything different and I don't know if it impacts anything as the first half of the tank went just fine with the CO2 valve leaking slightly.


Help....

[lhall]

Wow, good times.

On the fill sensitivity, check for those broken springs inside the fill head. That made a big difference for us. Also, make sure that the area around the fill sensitivity wire connections is clean. We had a problem where, after we had greased up the fill head, there was excess grease making a connection between the fill head and capacitance wiring. Drove me crazy until I wiped all the excess grease away.

[grs]

Thanks for the reply Linus. The wires for the fill sensor were clean and dry. A month ago or so I even went so far as re-routing them so they wouldn't be as exposed and as susceptible to getting beer on them. I am going to check the wire insulation for cracks, though. Maybe even change out the wires. My electrical theory is a little old and dusty so does anyone know if the length of the fill sensor wires or the gauge of wire will affect the fill sensor?

I guess one band-aid solution would be to program a delay timer in the controller so that it ignores the fill sensor for approximately 2 seconds after the fill valve opens but I'd rather find out the root of the problem and fix it there. Plus that may just result in 1/2 filled bottles indexing through.

[lhall]

Have you tried calling Dave Meheen? In my experience he has been pretty open and helpful, if you have a clue what the problem is.

[Meheen]

If your machine is using the old safe cracker knobs and Warrick relay inside for fill detection, there are a couple of possible causes. So here are a few things to look at. Acid sanitizers splashed around can form a conductive film on the outside of the wires, which it sounds like you have already checked. Next you should clean the springs and docking stations with a scotch pad and clean water to make sure they make good contact. Some times you can get a little moisture in the twist plug in the bottom of the panel which will cause this sort of problem. So take the plug apart and make sure it is clean and dry. Another possibility is the pot on the back of the safe cracker knob is going bad or you may have poor connections between the docking boss on the fill head and the SS off-gas tube. This can be checked with an ohm meter.

Here is a simple test to see if your fill detector is working properly. If you put the fill head down without bottles and no compressed air and open the control panel door with the power on. Turn the knob to about 150 or so and touch the two outside off-gas tubes with your hands. The light on the Warrick should light indicating a fill detected. keep doing this and turning the knob down. Somewhere around 50 the light should stop coming on. This will vary as to number that fill detection stops.

Dave

[grs]

Well, I found the springs Linus was talking about and although they aren't broken, they were squished so they weren't really that 'springy' anymore. I've replaced them and reassembled the machine. We'll see on monday what happens.

I also found that one of the studs that screws into the fill head, pressing the spring into place against the fill tube, was rather loose so I'm thinking that that coupled with the squished spring resulted in a less than stellar connection.

grs