My Renold 3/32" chain, that I bought N.O.S. about two years ago was riding just fine last year. It is on a cycle that I do not use in wintertime, so it sat for 6 months. I was experiencing some gear slipping a few days ago, on my first ride of the season with this bike, so I tried to determine the cause. The chain is not stretched (only 1/32") and the teeth on my freewheel (upon visual inspection) seem like they have some life left in them. My plastic derailleur pulleys have seen better days, but I did (do) not think they were the reason for the gear slipping. I looked at the chain more-closely, and saw that it had some dried oil with dirt on it, that would not wipe off. I soaked the chain in Coleman fuel overnight, and it had no effect. I am now slowly and carefully going about the job of scraping and digging (with the small blade of my Swiss army knife) the encrusted, dirty oil off both sides of the interior and exterior plates and from around the rivets. I'm about halfway done and have put in about two hours. I'm not complaining, and actually feel happy that my conflict may be near a resolution. Since you are already riveted to this discussion, could you answer, "Are these old chains more prone to having old chain lube attach to them more tenaciously than contemporary chains?" (I used whatever I spontaneously chose: Chain-L once in a blue moon, Green Oil occasionally, Zoom Spout Turbine every now and then and usually Finish Line wet). I have always wiped my chain down and although I have not endeavored to take the chain off the bike and scrub it every year, this kind of situation has never happened to me, before.

Coleman fuel is essentially denatured alcohol.
You are going to need a stronger solvent.

I am in California, it is becoming really difficult.
lacquer thinner might be how you need to go.
the old "white gasoline" would do it but fire and MSDS danger.

the original lube for those chains was almost cosmoline.

Since you are scraping link by link, you might want to brush pairings of links with an old toothbrush or a fine bristle brass brush.

silica suggested chain cleaning protocol: 1) soak/agitate in paint thinner 2) multiple soaks agitation as needed in citrus based chain cleaner 3) soak in acetone use compressed air to blow out links after first 2 steps

Right after I soaked it the first time in Coleman fuel, I tried a tooth-brush dunked in Coleman fuel. It had no effect.

Repechage: I don't mind going at this manually. I'll take the chain off and go over it after every season from now-on.

Squirtdad, Do you think a Goo-Gone soak would be more effective than Coleman fuel? If so, that would save a lot of work and present fewer health hazards.

I went on a 3 week summer road trip to Texas a few years ago and had my commuting bike locked to my car's bike rack the whole time. The Rock-N-Roll gold chain lube that I was using back then baked onto the chain and my chainrings and cassette cogs and when I went to do maintenance on the bike when I got back. The old chain lube turned a black color and stuck to everything. It did not come off even in a gasoline soak. I ended up tossing the chain and ended up doing multiple scrub brush treatments on the cassette cogs and the chainrings and eventually got most of the black stuff off. It was almost like a teflon coating!

Did you try to ride the bike?

Yeah, I mean I was doing club rides down there like every day with the Houston Bike Club. I met some really nice people. The chain ran OK, it was silent. I just always want all my parts to remain as clean as possible that's why I set out to scrub everything thoroughly when I got back home.

I had good results on chains with old, caked grease using WD-40.

My 'deep clean' chain routine is put the chain in a large jar (I've got one that protein powder or something came in- wide mouth, probably about a half-gal volume) cover it with mineral spirits, close the jar and shake it for a minute or so. Let it sit overnight. If I think of it, I give it a shake now and then. Pull out the chain and wipe it down well with a rag or paper towels. Pour off the mineral spirits into something for proper disposal later. Wipe out the jar, getting all the grit and residue. Repeat. If it's really bad, repeat again. Usually the mineral spirits from the second/third soak can be kept and used for the first soak next time. Then I do the whole thing again twice with denatured alcohol (and same thing- keep the second batch of alcohol to use for the first next time around). This usually results in a very clean chain. I use wax on my chains, so I do this routine with new chains, too- but it's worked well on some really gunked up chains on old/neglected bikes I've bought.

Where is "mineral spirits" available? Is it volatile/dangerous?

Were you able to just wipe off the grease after allowing the chain to soak?

Well, I don't think it's available in CA, so it's probably dangerous-ish... Definitely want to wear rubber gloves and eye protection when using it. I believe it's a more refined version of paint thinner. I get it at my local hardware store.

paint thinner and mineral spirits in California have been emasculated to the point that they are useless. "Low VOC" and Ca prop 65 have upturned the landscape. Diesel fuel or kerosene are better but not much.

I have near full gallon containers that will eventually go to the hazardous waste roundup.

a number of products have shifted to acetone based formulations, such as things labeled industrial solvent.

stay clear of simple green.

goo gone might work, might.

there was a good 3M adhesive remover, the California formulation is now acetone based by performance, the prior good stuff is not available in California.

toluene? Not in California.

I applaud states like California taking a dynamic stance for environmental and personal health. I just hope and wish corporations label their products accurately. For example, I recently bought some Ready-Strip (environmentally-friendly) paint stripper. I used it in the temperature range they indicated. It did not even work. I think we better get used to the idea of using more elbow-grease.

Yes, with an old toothbrush. I tried gasoline and paint thinner but WD-40 was much better.

I just bought a new fine wire wheel brush for the hand held drill for scrubbing the old gunk and rust off chains.

[MENTION=160128]1989Pre[/MENTION]

My 2c, lifelong auto mech/tech a lot of carbon cleaning, removal experience.

PB Blaster

Carburetor/intake cleaner, CRC, Gunk, Berrymans, Gumout, Motorcraft PM-2, nasty stuff, proceed with caution.

Brake cleaner, chlorinated is best.

Soak and scrub with wire brush, repeat with no rinse, emulsified gunk will help the next soak break down the remaining stubborn grime.

Again, be careful, gloves, safety glasses, mask/respirator, work in a big pan and soak in a sealed container to retain vapor/fumes to help do the work.

You're absolutely right about the elbow grease no matter what else.

I soak old chains in kerosene. Walmart sells it in small quantities in a blue bottle in the camping section. Kerosene cleans and lubes.

Ok, so it is not the design nor materials of the older chains? I'm wondering why I've never had this happen before, but most of my other chains are more-recent than this 1970's Renold. I'll have to keep an eye on my chains more-closely if this is something that is common. i should be able to test the chain out tomorrow. I hit it with a good amount of WD-40 yesterday, and am still scraping the chain's outer plates and digging around rivet ends.

You shouldn't have to pick and scrape, soak, scrub with brass or stainless wire brush and or scotchbrite.

You're not listening. I soaked the chain in Coleman fuel overnight. It had no effect. I do not own these types of brushes, but could have gone at it with a stainless steel sponge, but two problems; my finger-tips would have been rubbed raw within five links and I can do a much-more-thorough job with the knife.
I was not asking for tips on how to clean a caked-up chain. What I sought an answer for is the question: "Are older chains more susceptible to being caked-up?".
A Scotch-Brite pad? Are you kidding?

Paul, pictures of the chain in question and the embedded gunk would be helpful. As much as anything, all of us, [MENTION=425004]merziac[/MENTION] included, have not fully experienced what you describe.

Personally, I'm having a difficult time imagining what you are experiencing. I've had some freewheels come through my hands which had been used with wax treated chains. I had to use putty scrappers to do the initial cleaning. I wondered if the chains were as bad. I've never had this occur to any of my chains, especially in such a short amount of time.

No.

That's right this thread needs pictures of crappy chains. Here's the Brampton crud and rust a number of frozen links.

I'll take an after later today.