No but I wish I did. I could shake the jar while I watch the world cup tonight
Jonsered Chainsaws
- Thread starter briantutt
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USC's are the *****....they usually get the stuff in that screen just behind the little Welsh plug. Even that carb soak stuff doesn't always get what's caught in that screen.
If the saw still isn't running right after you put the carb back in....you should take out that Welsh plug and examine the screen. Though if you have the rebuild kit, it should have that little Welsh plug in there....you could do it now.
Kevin
If the saw still isn't running right after you put the carb back in....you should take out that Welsh plug and examine the screen. Though if you have the rebuild kit, it should have that little Welsh plug in there....you could do it now.
Kevin
The girls bought me a little one for jewelry for less than $40. It works pretty well but not that great at getting main nozzle check valves cleaned out. I took a self contained one out of a Poulan 8500 carb and put it in the USC and it worked well but not so good when the valve was in the saw.
The Makita MCS 520 I picked up has the capillary screen type. I put the carb immersed in Sea Foam in a special plastic container (pudding cup) and stuck that in the USC with water in the USC bowl. Cleaned the screen right up in two cycles,
Carb kits generally come with the capillary screens but pulling the clip holding the ring is like pin striping with a whitewash brush.
Messed up main nozzle check valves can give you a painful bunch of tuning issues.
I bought my USC @Harbor F.......I know from reading the reviews that if you put straight chems in the tank, it won't last. However, if like Tim says, you put water in the tank and your chem solotion in a glass jar then lower it into the water (should have roughly the same level in both), your USC should last.....unless you drop it.
I think mine sets up for an hr max. The ones that go for 15 minutes are not gonna work without repeated cycles.
Kevin
I think mine sets up for an hr max. The ones that go for 15 minutes are not gonna work without repeated cycles.
Kevin
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I have a 6 ltr USC...with 185 degree heat and 1 hour timer. Works great when needed. One trick I use to determine if the carb needs to go in or not is pretty easy. Pull the H&L needles...then with the red straw on your WD 40 (or whatever spray can) slip the straw into the "L" opening, bottom it out and while holding the throttle plate open give her a squirt or two.....should be a good amount coming out of both idle orifuses...one in front of where the plate closes, the other behind. Do the same with the "H" and there should be a generous amount squirting out the main fuel jet. This is how I check the carb after it comes out of the USC too. You can generally tell if you have an obstruction by a reduced flow...
I have a vintage usc. It only has an on and off switch. I can let it run all day long if I want. It doesn't have heat but after about an hour the water gets pretty hot on its own. This thing is so old you can see the vacuum tubes lite up when you look in the side vent!
I rebuild lots of vintage tractor carbs. Always put the straw on the carb cleaner cans. Spray through the passages to check for flow and blockage.
I agree....works like a champ!
I've seen pics of your USC, Robin and it ain't no Harbor F unit...lol. Even on eBay the good commercial ones used, can run hundreds of dollars.....at least the ones that most likely work....lol!
Kevin
Old school
. I didn't know USC's went back to the tube era (or for you UKers-'valves'). I certainly didn't hear about them until solid state electronics. First one I ever saw was a jeweler model, but they've been used commercially in industry for a long time....obviously longer than I know about. Some tubes are worth a small fortune if you happen to have a specific kind.....people have gutted old equipment just to sell the tubes off.Can you take a couple of pics of 'er? I'm curious.
The litmus test for checking these units IIRC, is to put some aluminum foil in the main compartment with some water. It should perforate the foil with tiny holes if it's working properly.
Kevin
Will get some pics for ya!
Old school
Can you take a couple of pics of 'er? I'm curious.
The litmus test for checking these units IIRC, is to put some aluminum foil in the main compartment with some water. It should perforate the foil with tiny holes if it's working properly.
Kevin
Here ya go Kevin.
Wow...thanks! Now there's a trip back in time...lol!! The size of the basket suggests it was an old jewelry USC or maybe a industrial shop that had smaller parts to clean for machinery etc.
It's like the moniker of a ham site I belong to: "Real radios glow in the dark."
Kevin
I bought it from an older gentleman friend of mine for $10. He bought it on an auction sale for dirt cheap. Nobody knew what it was. Works great!
No provenance. Oh well, it works great and that’s the important part!
Kevin
Kevin
Well the magic Sea Foam did not solve the problem. I guess I'll have to dig deeper. Under the Welsh plug we shall go.
I've never gone that deep. Carbophobia.
Cory (Hoggwood) has done at least one of those. PM him, he may have some tricks on digging the clip out. There's a special tool for it I think from Walbro but he's likely circumvented that.
Looks like someone may have been there already
If someone has messed with the welsh plug make sure it isn't leaking.
It looks like the welsh plug was pried out with a sharp object and has been replaced. Don't know if it is leaking.
Symptom: saw starts, revs and dies as if it was turned off. Revs for 2-3 seconds only then cuts.
Oddly enough I also have a Husky with similar HDA carb and it is showing the same symptoms.
Getting a hate on for these carbs.
Symptom: saw starts, revs and dies as if it was turned off. Revs for 2-3 seconds only then cuts.
Oddly enough I also have a Husky with similar HDA carb and it is showing the same symptoms.
Getting a hate on for these carbs.
Kensie1988
Vintage Saw Maniac
That definitely sounds to me like lack of fuel, I've had similar symptoms from saws and it all turned out to be fuel delivery
