JeffOYB

I have a Suntour Powerflo 7-sp freewheel that is making weird sounds under load. I squirted WD40 in it then Boshield then some oil and worked it some and the sounds got curiouser and curiouser. Some 'gloppy' sounds. So I took it off the wheel. It feels pretty chunky spinning it on my finger. Is there a good way to spruce it up? Should I soak it in solvent, rinse and spin? Relube? Heavy oil? What does it like? (It's on my fave CX wheel.)

HillRider

How about the simplest approach, replace it with a new freewheel.

JeffOYB

dang where's the mechanic spirit? this isn't the "R&R remove and replace" forum! ... i never replace anything until it's known to be definitively broken and can't be fixed. i've got a bunch of old stuff that seems to keep going and going. ...but when it's dead i'll accept it!

HillRider

From the description in your OP, it's indeed dead. Play taps and give it a decent funeral. There are things worth fixing and things that aren't. A Sun Tour freewheel of that vintage is one of the "arent's".

JeffOYB

do freewheels like to be swished around in solvent to get rid of gunk? what kind of lube scene do they like?

FBinNY 

IMO probably not.

Freewheels are like electronic ignition in cars in that they only have 2 modes. They either work --- ie. transmit power under load, and ratchet when the wheel overruns the chain --- or they don't. The 2 failure modes are no power, or no coasting.

If a freewheel works, but is sticky or noisy it's almost always OK except full of dried lube, dirt or rust. These respond very well to a process of soak to loosen crud, spin ro work it out the gaps, repeated until the mechanism is clean and free running. Then drain and re-oil by running a thick oil that doesn't not set up (no grease or waxes). Let the excess drain, and it'll run like new.

People obsess over freewheel lubrication, but they really don't need any because of how they work. You can't get wear under load because there are no moving parts under load. parts only move when your coasting, and the only load is the weight and tension of the (unloaded) chain. At those tiny loads, wear will be minimal, and the real purpose of lubricant is to prevent totally dry metal contact, and to keep water out so the internals don't rust.

HillRider

It's also to keep the pawls moving freely so they engage when they are supposed drive to and stay clear of the ratchet when they are supposed to freewheel. Dried, stiff or dirty lube won't do this.

FBinNY 

No and yes.

The pawls will spring back and forth when dry as well or possibly better than when lubed. After all, what's to prevent that. But you're right that dried, thickened oil or grease or dirt can cause pawls not to engage properly, either by adhering them in the retracted position, or by filling the corners of the ramps so they can't open completely and might hang on the edge and slip off under load.

There's a certain irony here. For almost a century, folks oiled their single or multiple freewheel systems, and all was good. They somebody got the brilliant notion that oil wasn't good enough and promoted the idea of greasing. Like all bad ideas it caught on, and became THE right way. Soon enough we started seeing issues of freewheel slippage under load, and manufacturers were sending tech advisories warning shop mechanics against greasing freewheels.

Despite that some people still think that greasing a freewheel is somehow better than simply oiling it. Proof positive that bad ideas never die.

fietsbob

Tried the sheep dip method? immerse it in Solvent, then when that cleans out the old oil , immerse it in clean Oil.

remove the cogs first and you wont need so big a can to fit the body in.

HillRider

Yeah, I remember the "Morningstar Freehub Buddy", a tool that made injecting grease into a freewheel or freehub easy and made it seem as if it was a good idea. It wasn't. Perhaps you could get away with using something relatively light like Phil Grease but using a heavy body lube like wheel bearing grease is a recipe for serious problems, particularly in cold weather. Oil is more than enough.

All I've ever lubed my freewheels and freehub bodies with is Tri-Flow and I've never had one fail in any way, including an older Dura Ace freehub with over 57,000 miles that still works perfectly.

Homebrew01

My freewheel cogs wore out long before the bodies ever needed maintenance. And restoring a neglected one always seemed like too much trouble. So I would dribble in a little 10w-40 every once in a while until it was replacement time.

I know Pastorbob and a few others seem to enjoy overhauling freewheels, but "Ain't Nobody Got Time fo' dat !"

NukeouT

The right way is to take it off, remove any grime off the front plates drip on some BioShield so it seeps in the slit between the front plate and rotating edge and then spin it on your thumb for about 10 minutes until the old black oil/grime starts coming out the back side.

1: try spinning it for longer with the highgear facing up and a bit more BioShield

2: dont use W40 unless youre trying to get a rusty FW that does not spin to spin

alcjphil

I have taken lots of freewheels apart. It is finicky work but it can be done. 7 speed freewheels are harder because you have to take the smallest sprockets off before you can remove the lockring. You need 2 chainwhips to do this. The lockring is reverse threaded, usually removeable using a small ended punch. Once you get that lockring off, you are on your own, there are what seems like a thousand 1/8" ball bearings in there and the pawls for the ratchets have numerous designs. Some are easier than others to put back together. It can be very unrewarding. You can take one apart only to discover that the internal parts are beyond repair. The only consolation is that these things are far easier to take apart than they are to put back together by a ratio of about 25% to 75%. So, If you take one apart only to discover that it isn't worth it to put it back together, you only wasted 25% of the time you would have if you reassembled it only to find out it still didn't work

wschruba

Freewheels are pretty easy to put back together, in the grand scheme of things. The trick is that most people now don't know how to work on them; there is an excellent article written about it on Sheldon Brown's website, but the gist is this: the most difficult part is re-seating the pawls without dislodging any of the bottom (inner) row of bearings. You can trawl ebay hoping to find a pawl clip to hold them down while inserting the freewheel shell, or you can use a thin strip of inner tube with a piece of thread tied around it. Put everything together, pull out the tube with the thread, and load the top bearings. You'll take care to note that the rows of bearings are usually full compliment, minus one or two--this is normal.

What everyone is trying to tell you, though, is that it is almost never worth doing for anything but a rare vintage freewheel, considering that by the time they are making strange crunchy noises, they're usually beyond fixing by cleaning.

JeffOYB

I'm liking this. I was wondering about how to get old gunk out of these things, given that the openings are slim. But I like this idea of squirting in lube from the top, rotating, letting old stuff come out the bottom. Then flip over.

But about WD40 ... I was thinking that a first course of treatment with solvent might be good for dissolving gunk and getting it to flow out. So do that for awhile at first, until no more juice is coming out either side. Then switch to Boeshield and repeat -- so that the Boeshield replaces the WD40. ...Hopefully. Someone suggested thick oil instead of "wax" -- which is what Boeshield is, I think.

Well, I did do some treatment then when out and rode it a day later and the sounds are at least different. I'll get more serious about this quoted idea about "flushing."

trailangel

Thick oil , not Boe****.

Dave Mayer

Freewheels are discard items for me. When they get crunchy or the cogs wear out, then into recycling.

However, I have a Suntour Winner Pro unit that I need to keep running, due to its unique cog spacing and cog composition. I have been running this freewheel hard in wet conditions for the last year, so yesterday I committed to a servicing.

It took about 45 minutes from the time I pulled the wheel off of the bike to the time the wheel went back on. The servicing was a complete disassembly, cleaning and reassembly. Right down to the gazillion little balls. I use a small amount of lightweight grease on the 2 rows of bearings. Oil on the pawls.

Works great now. The Winner Pro is a very nice unit - better design and materials than almost any other freewheel I've pulled apart. The 7-speed Dura-Ace and Sante units are also worth saving.

Bill Kapaun

I have a hunch you've done this before??

fietsbob

NWP freewheels have a lubrication hole uncovered when you remove them from the Hub.
Through that hole You put the fresh oil In

the labarynth sheilding on the outsides prevents most contamination ,
but also resists trickling oil in the gap between those 2 moving Parts .

brian3069

I think the Powerflo is a cassette, not a freewheel.