Welch plug help
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Fingernail polish is what I've heard. Personally, I've never removed a welch plug.
PB
Addicted to ArboristSite
I have never heard of the fingernail polish before. I though that the pressure would hold it in there when you press/punch it in there. They are hard enough to get them out, can't imagine they would come out on there own. In any case, I don't replace them either. In all the carbs i rebuilt, i think I have done 2 out of 30 or 40.
Ive never used sealer.If the plug is well seated before you "punch" it,there should be no leak.Once installed,put a bit of oil over the plug and blow air tru the corresponding needle hole.If bubbles,then,punch a bit more and recheck.If you got leak,the saw will run rich.And before removing it,direct your tool at angle away from the needle to not damage the needle hole area.
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Lakeside53
Stihl Wrenching
NEVER use sealer - even the factory sealer from Zama has become a service problem with the "new gas".
Just place the welch plug in the hole/recess, and tap it lightly on top with a suitably shaped punch to distort it. (you may need to grind one if you don't have a zama/walbro tool kit) Tap it too much and you'll make it loose...
Blowing compressed air not recommend in newer carbs -they have internal NON-replaceable check vaves that get damaged.
Just place the welch plug in the hole/recess, and tap it lightly on top with a suitably shaped punch to distort it. (you may need to grind one if you don't have a zama/walbro tool kit) Tap it too much and you'll make it loose...
Blowing compressed air not recommend in newer carbs -they have internal NON-replaceable check vaves that get damaged.
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PB
Addicted to ArboristSite
Hey Andy, how many carbs do you think you have rebuilt? 1000? 10,000? LOL.
I think I have experience with 30 or 40, pretty pathetic.
Lakeside53
Stihl Wrenching
lolol no idea... has to be over a thousand by now... but some of those are just diaphrams.
30-40 is pretty good start!
30-40 is pretty good start!
AZLOGGER
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The use of fingernail polish is just cheap insurance against any leaks, easy to apply, then smack the welch plug with small hammer and flat punch, just enough to make it flat. I have removed many, when rebuilding carbs, sometimes there is a little bit of crap under the welch plug. This procedure is not necessary if the fine inlet screen is in the carb and is pretty much clean of foreign material.
JFYI
The reason for fingernail polish, is gasoline fuel mix will not remove it nor deteriorate it.
Lakeside53
Stihl Wrenching
Are sure about that with ethanol gas? I've seen many where the polish has lifted off or got soft. No idea if they were using Revlon Blush, or...
Zama's pale green sealer has cost Stihl (and I'm sure others) a ton of $$ with warranty claims. They have abandoned it on later carbs. It almost drove me crazy on a few saws - floating around in the metering chamber as an almost invisible part. I've seen plenty with tiny portions jambed in the main jets.
Zama's pale green sealer has cost Stihl (and I'm sure others) a ton of $$ with warranty claims. They have abandoned it on later carbs. It almost drove me crazy on a few saws - floating around in the metering chamber as an almost invisible part. I've seen plenty with tiny portions jambed in the main jets.
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super3
Addicted to ArboristSite
It's an older ws26 carb, I put a complete kit in minus doing anything to the welch plug. On an 076 super.problem is in the cut,quite doggy
Welch plug removal can quickly turn into a "bundle of snakes". It is best to try to establish flow to the cross drill passages and on to their end destination WITHOUT removing the plugs. In most cases we can use some spray can brake cleaner and determine if we have any obstructions at the intersections of the drilled passages under the plugs. Most of the time if you can establish flow on to the end destination, things will be fine. Once in a while you are simply going to end up with running problems, requiring the removal of the plug(s).
If/when they need to be removed, they will usually re-seal fine, but there is always one in 20 or so that's going to give troubles. It's not a 100 percent guarentee that you will not be buying a replacment carburetor when you go as far as to remove the plugs. My success rate here is close to 100 percent, but we do this for a living, and have the experience needed to end up with a good result in most cases. This is simply because I've messed up enough of them to get really good at these sort of repairs!......Cliff
cliffshighperformance.com
If/when they need to be removed, they will usually re-seal fine, but there is always one in 20 or so that's going to give troubles. It's not a 100 percent guarentee that you will not be buying a replacment carburetor when you go as far as to remove the plugs. My success rate here is close to 100 percent, but we do this for a living, and have the experience needed to end up with a good result in most cases. This is simply because I've messed up enough of them to get really good at these sort of repairs!......Cliff
cliffshighperformance.com
Lakeside53
Stihl Wrenching
Hmmm.... I doubt that's your issue them - the WS26 doesn't have a welch plug... Did you remove the screws to the cover in the bottom of the metering chamber and replace that gasket etc?
Did your kit have the "hook-on" type of metering diaphragm? if so, did you hook it?
Does the saw sound like it's running nice? - not 4-stroking" when in the cut?
What does your compression feel like without use of the deco valve.
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crane
Addicted to ArboristSite
great thread, I have 3 HL carbs sitting on the bench waiting for time to get new kits in. Was going to pop the welch plugs, but will reconsider.
super3
Addicted to ArboristSite
Yes,yes,yes,if h is 3/4 or less,no decomp,it'll break yer arm
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Lakeside53
Stihl Wrenching
Then it's unlikely your carb...
AZLOGGER
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Are sure about that with ethanol gas? I've seen many where the polish has lifted off or got soft. No idea if they were using Revlon Blush, or...
Zama's pale green sealer has cost Stihl (and I'm sure others) a ton of $$ with warranty claims. They have abandoned it on later carbs. It almost drove me crazy on a few saws - floating around in the metering chamber as an almost invisible part. I've seen plenty with tiny portions jambed in the main jets.
Andy:
The stuff I use, I snagged from the wife, its from AVON and you have to use their remover to get it off, rubbing alcohol won't even touch the stuff.
I agree on the green crap, its on the Zama's used on Husqvarna's, it's also caused me alot of frustration. Spending 1 to 2 hrs rebuilding a carb then trying to dial the engine in, not very profitable.
Ax-man
Addicted to ArboristSite
Welsh plugs are a royal PITA. Best to leave them alone.
This is where pressure testing the carb comes in handy to isolate the problem. If you have air bubbles coming out the venturi it is either a leaking Welsh plug or the inlet needle isn't seating.
I am going to pass this along. Try it at your own risk to change one if you can't seal the welsh plug using a sealer like fingernail polish.
Instead of the conventional method to change a welsh plug. Use a drill press with a small bit to drill a hole through the plug then pry it out. Takes a very light touch and a good feel to know when your through the plug. Drill toooo far and you ruin the carb passages. Keeping the carb clean is very important if you do this.
To reinstall the plug take your punch and mount it into the drill press. With the machine turned off use the drill press like a press to flatten the dome of the welsh plug to seat it. Again a light touch is all that is required. Toooo much force and it will leak.
I have done quite a few welsh plugs like this with good results only because I am not that good with a hammer.
I have tried the fingernail polish. I haven't any luck with it to speak of. Works for awhile then degrades and the problem your trying to solve comes back to haunt you.
Larry
This is where pressure testing the carb comes in handy to isolate the problem. If you have air bubbles coming out the venturi it is either a leaking Welsh plug or the inlet needle isn't seating.
I am going to pass this along. Try it at your own risk to change one if you can't seal the welsh plug using a sealer like fingernail polish.
Instead of the conventional method to change a welsh plug. Use a drill press with a small bit to drill a hole through the plug then pry it out. Takes a very light touch and a good feel to know when your through the plug. Drill toooo far and you ruin the carb passages. Keeping the carb clean is very important if you do this.
To reinstall the plug take your punch and mount it into the drill press. With the machine turned off use the drill press like a press to flatten the dome of the welsh plug to seat it. Again a light touch is all that is required. Toooo much force and it will leak.
I have done quite a few welsh plugs like this with good results only because I am not that good with a hammer.
I have tried the fingernail polish. I haven't any luck with it to speak of. Works for awhile then degrades and the problem your trying to solve comes back to haunt you.
Larry
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I'm no expert but did the plugs for the first time last summer,, piece of cake, no sealer, no problems. Saw runs great. I think the carb web sites even have the 'PROCEDURE'
I would do them again.
Now back to my MGD
I would do them again.
Now back to my MGD
The instruction sheet from Walbro Tool Kit No. 500-500, Diaphram Carburetors, states:
"Welch Plugs: Remove "L" and "H: needles, and gently drive tool #500-16 punch into welch plug at a low angle and gently pry loose. Welch plugs are replaced by using tool #500-15 and striking gently until crown is flat only. (Do not cave in Welch plug). It's a good idea to seal Welch plugs with a thin coating of nail polish."
Doesn't say what color of nail polish to use.:greenchainsaw:
"Welch Plugs: Remove "L" and "H: needles, and gently drive tool #500-16 punch into welch plug at a low angle and gently pry loose. Welch plugs are replaced by using tool #500-15 and striking gently until crown is flat only. (Do not cave in Welch plug). It's a good idea to seal Welch plugs with a thin coating of nail polish."
Doesn't say what color of nail polish to use.:greenchainsaw:
