Welch plug help

[mattmc2003]

I know i passed out one time.....could have been the vodka...im not sure though. And i woke up and my toe nails were painted. Nothing would take it off short of nail polish remover. Carb cleaner, nor brake cleaner, or gas. I found out that nail polish remover was the stuff.... i just had to explain to my sister why i needed it.

 

[stihl86]

"Seal=All" by Eclectric Products has been working for me.

 

[Lakeside53]

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:

I wonder if they wrote that 20 years ago Walbro no longer uses any sealer in Stihl carbs.

In a shop enviroment, it's a problem anyhow - no time to let it cure properly (over night?), and if you don't it will wash away... I still think the newer gas loosens it over time.

I'l stay with dry fits.

 

[Lakeside53]

I know i passed out one time.....could have been the vodka...im not sure though. And i woke up and my toe nails were painted. Nothing would take it off short of nail polish remover. Carb cleaner, nor brake cleaner, or gas. I found out that nail polish remover was the stuff.... i just had to explain to my sister why i needed it.

Traditional Nail polish remover is pretty much just acetone. Many carb cleaners are acetone based.

NON acetone remover has ethyl alcohol and ethyl acetate...
example: http://www.vijon.com/data/resources/PN688.pdf


There are many variations...

 

[BIGBORE577]

I remove and replace the Welch plug if I do a carb rebuild. I've found some real surprises under them, especially with older vintage saws. Some definitely would have not run if they had not had the plug removed and cleaned under/to/from them. I don't know what the issue is, it takes about 3 minutes to do, far less time than removing and reinstalling the carb again if it needed to be done in the first place. I tap them down a bit to loosen them up and they either fall out or you can snag it with a dental pick. Clean underneath, reinstall plug and tap it gently with an appropriate sized punch until it has a tight fit. I don't use sealer and the carbs all work fine. That being said, I can't say I never used a sealer. I've had a couple older saws that gave me some fits with not running properly after a carb rebuild. I thought the problems may have stemmed from a leaky/loose Welch plug after reading here about using salers and I had not. I disassembled the carb and used nail polish as a sealer. When the problem persisted and I disassembled the carb once again, I found the polish to be soft and far to easy to remove. I felt that it would dislodge from the vibration of a running saw. In another instance, I removed a Welch plug and attempted to reuse it since I had no other to use as a replacement. I used a thin bead of JB Weld to hold it in place and act as a sealer. I tore that carb down about 3 months later because, knowing about The JB in the carb did not sit well with me over time, I wanted to remove it and replace the plug with a new one. I was surprised to find the JB soft and far to easily removed like the aforementioned nail polish. None of these saw's problems were the result of a loose or leaking plug. I'm sure there might be better/proper sealers available. I won't be using them, since I haven't found the real need to do so. Perhaps the necessity will arise in the future but, not as of yet.

 

[Cliff R]

JB Weld will NOT hold back fuel in constant contact with it. Use Devcon or Marine Tex. Marine Tex is readily available, and if it is used on the out parimeter of the plug it will seal minor imperfections permanently. None of the commercial grade epoxies will stay in place if you just "dab" them over the plugs. If you very carefully coat the edges and drive the plugs into place, then wiped off the excess, they will seal fine. Make sure to let them sit for at least 24 hours before using the carb, and it really helps to warm the carb with a hair dryer or set it over a hot air vent, etc for a couple of hours.

We build carburetors every day here, and very seldom have any troubles, we typically do NOT use any sort of sealers, unless the plugs fail the leak test (soap/water solution and compressed air).......Cliff

 

[BIGBORE577]

JB Weld will NOT hold back fuel in constant contact with it. Use Devcon or Marine Tex. Marine Tex is readily available, and if it is used on the out parimeter of the plug it will seal minor imperfections permanently. None of the commercial grade epoxies will stay in place if you just "dab" them over the plugs. If you very carefully coat the edges and drive the plugs into place, then wiped off the excess, they will seal fine. Make sure to let them sit for at least 24 hours before using the carb, and it really helps to warm the carb with a hair dryer or set it over a hot air vent, etc for a couple of hours.

We build carburetors every day here, and very seldom have any troubles, we typically do NOT use any sort of sealers, unless the plugs fail the leak test (soap/water solution and compressed air).......Cliff

This is good information, thanks. While I have not had issues with any of the Welch plugs I have replaced up to date perhaps, I should re-examine my stance on sealer. Maybe it is a good idea to use the Marine Tex as you described as insurance.

 

[alpinecrick]

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.

Fingernail polish, at least the old fashioned stuff, is lacquer based--petroleum products won't dissolve lacquer.

Now if you happen to be running nitromethane in your saw......or lacquer thinner mix..........

I wonder if the saw/carb manufacturers were using a sealant that was petroleum or water-based, and the alcohol blend fuel was dissolving the sealant?


Casey

 

[alpinecrick]

After reading through the thread it looks like a lot of guys are having problems with fingernail polish. The stuff I use (Passionate Red ) has got to be 10 years old. I've had to thin it down a couple times with lacquer thinner to get it to come out of the bottle.

I'm thinking the new polish is probably not lacquer based anymore (EPA has reared it's ugly head again). Seeing as how I'm about outta' Passionate Red and getting ready to install a couple carb kits, I think I'll check out the fingernail polish aisle at Wal-Mart and see if the polish has gone Green or sumthin'......


Casey

 

[litefoot]

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).

That's what I was thinking, too. And in addition, most of us have time to soak the carb overnight in a carb cleaner or solvent if we have to...and then jet out the orifices as you suggest.

 

[Lakeside53]

I suspect it also depends on what is in the "gas" (other then alcohol). For example, Cheveron adds "Techron" - an injector/carb cleaner.

Check out the junk in that product!

https://www.cbest.chevron.com/msdsS...522&docFormat=HTML&isLoginPage=true&region=NA

 

[alpinecrick]

I suspect it also depends on what is in the "gas" (other then alcohol). For example, Cheveron adds "Techron" - an injector/carb cleaner.

Check out the junk in that product!

https://www.cbest.chevron.com/msdsS...522&docFormat=HTML&isLoginPage=true&region=NA

Naptha will dissolve lacquer based products in a heartbeat. I was going to mention gasoline additives--I have some shirttail relations who own a bulk plant, and they say the additives are what differentiates different brands of gas. I suspect the additives and cleaning agents are as much to blame as alcohol blended fuels in some cases--even AV gas has additives.


Casey

 

[Urbicide]

A friend of mine told me 30 yrs ago that all of the local gas in the area (Augusta GA) came from one terminal. The difference between brands was in a bag of additives that the driver would dump into his tanker while it was being filled up before a run. Each brand of gasoline had its own specific additives. Sure cuts down on the number of pipelines that would be required.

 

[Lakeside53]

That is still true out here - all our gas comes from the Anacortes refinery - the additives are all that change the brands.

 

[alpinecrick]

A friend of mine told me 30 yrs ago that all of the local gas in the area (Augusta GA) came from one terminal. The difference between brands was in a bag of additives that the driver would dump into his tanker while it was being filled up before a run. Each brand of gasoline had its own specific additives. Sure cuts down on the number of pipelines that would be required.

That's how it works out here--most of the gas in the southern and central Rockies comes out of the refineries in Denver, Cheyenne, or New Mexico, and the difference between brands are the "secret" blend of additives that each brand specifies.

Those additives are designed to clean fuel systems, and to control the volatility (how the fuel burns) --the additives can be the most erosive/corrosive/drying out of fuel system parts.


Casey