Autolite 4100 with frozen secondaries?

[Kerry j]

I hope this is the right forum But I have a 112 Autolite 4100 that's all there, but the secondaries are frozen solid. I took it apart as far as I could and soaked it for a day in Berrymans, but that secondary shaft is still frozen solid. Any suggestions or ideas about how to get that thing loosened up?

[jayb]

Kerry, I would soak it longer, up to a week if necessary.  Take it out of the solution every day, blow it off with compressed air, and try to work the throttle shaft.  Put it back in and repeat.  The operative word is patience.

I don't know if Berryman's is the right stuff for this, by the way; I'm not familiar with that stuff.  Is it just a solvent, or is it also a lubricant like WD-40?  You need a penetrating oil of some sort for that job.  If the Berryman's doesn't work after a while try WD-40 instead.

Last option would be heat, and I don't mean a torch.  Try just putting it in the oven at 300 for 15 minutes or so, and then see if you can work it loose when you pull it out.  Heat will expand the components, and help the frozen parts break loose.

Hope that helps - Jay

[Kerry j]

Thanks Jay, all those suggestions sound like good advise and I'm not in a hurry for this, it's not needed for anything right now.

The Berryman is what I've always used and what I've seen used most; here's a link to what it is:

http://www.berrymanproducts.com/Default.aspx?tabid=146

It usually does a great job cleaning up cruddy carbs and even on this 4100 it's work great except for the frozen secondaries. It's got kind of an oil feel to it, but I don't know that it's a great penetrating oil. I did squirt some Gibbs oil on it for a few hours before I soaked it and that did help me break the primaries loose.

I'll give the Berryman some time and we'll see what happens.

[babybolt]

Unfortunately there's no standard or easy way to loosen Autolite 2100 2150 or 4100 throttle shafts.  That the primary was initially stuck also is usually bad news for these carbs. 

Many times the 4100 secondaries will freeze because the vacuum diaphragm on the back of carb stopped working long ago and it doesn't take long on these aluminum carbs for the blades/throttle shafts to freeze up.

I've tried all sorts of methods and liquids.  Even blasting around the throttle blades usually does not seem to help but its a start on the worst cases.  Soak, heat, and work at it is the tried and true method.  I have about a 80 to 90% success rate, but then I learned which ones to toss early before getting a lot of time into them.

Don't give into the temptation to pound on the throttle blades, it rarely works.

Some of the carb cleaners do have chemicals that etch or can be a long term detriment to the metal.  Many years ago I ruined several carbs by letting them sit in carb cleaner for longer periods.  Since then the chemicals have been toned down quite a bit due to environmental rules.  The cleaners are also getting very pricey.  I try not to leave them in the nasty smelling stuff more that a couple of days.  Be sure to clean off the carb solution by dunking the whole thing in mineral spirits, or etc.