Air Ratchet Question

[mucksavage]

I have 2 3/8" drive air ratchets. 1 Craftsman Model 875-188020, about 20 years old, 1 Devilbiss (cheapie purchased in an air tool kit from Sam's Club) about 10 years old. I'm only a hobbyist, so they're not used too often.

Anyway, they don't spin. I can grab the 3/8 square & they'll turn in both directions, but when I hook up the hose & squeeze the trigger, the seem to blow air out from between the "handle" and where the " shaft & head" screws on. (Where the large nut is) I've run oil thru them regularly throughout their life. Any ideas on what would be wrong? (Sorry if I don't have all of the terminology right)

 

[Raven GT]

Could be that the blades are stuck in the rotor ( don't know if that's the right terminology, I'm dutch so... )

This happens sometimes at work on the air impacts, either some temp thinks oiling one is dropping half a bottle of oil in there
(say nothing , just wait till they hook it up and pull the trigger )
, or its just gotten dirty inside...

I usually spray some brakecleaner in the air inlet while pulling the trigger, let that sit for a minute, hook it up to an airline , run it in both directions for a few seconds so it can get rid of the "crud", unhook it, put a few drops of oil in, and run it in both directions for a bit longer, unhook, pul trigger 2/3 drops of oil and store or use.

 

[theoldwizard1]

There is ball in the throttle somewhere. It is severely rusted/pitted.

Part #8

 

[ScottsGT]

When I was in the bodyshop business, once a week I would run lacquer thinner through my tools and then re-oil with Marvel Air Tool oil. I never had the "motor" in any air tool fail on me. I did get a few worn out heads on air ratchets though.

 

[wild cowboy]

I second the Marvel Mystery oil - in the shop we call it "air tool crack" - lol

 

[mucksavage]

I tried the brake cleaner, nothing. I then took out (refer to above illustration) #5,6,7,&8. #8, in my tool is a rubbery, kinda plastic mushroom shaped thing. The stem on the mushroom seems to be on the spring and the ball, or cap of the mushroom is seperated. Could that be my problem? (It seems like it should be 1piece)

P.s. I've always used some kinda generic air tool oil, but I'll be sure to get some Marvel for future use.

Thanks!

 

[cheechi]

I have actually been meaning to ask this for a while now and haven't remembered. I saw the Lucas for the first time a few weeks ago, and it got me thinking. Aside from the usual amflo, IR, and of course everybody who makes nailers has their own label. is there a best? is marvel's the best?

I had an HF air ratchet that was sticking just like you described. flushed it with oil and wd-40 a bunch of black junk came out and it's been ok since. I got a CP since then, don't use the hf much so i can't say it was good long term, but it seemed to do the trick at the time.

 

[wild cowboy]

it is not an air tool oil from Marvel - it is Marvel Mystery oil - the stuff your Dad put in the crankcase back in the day - techs just accidentally discovered that it does great things for air tools #repurposed

 

[firebox40dash5]

it is not an air tool oil from Marvel - it is Marvel Mystery oil - the stuff your Dad put in the crankcase back in the day - techs just accidentally discovered that it does great things for air tools #repurposed

They make an air tool oil too. Or put regular MMO in a small bottle with a dripper top. Whatever, I buy it either way.

 

[Raven GT]

Anyone feel free to correct me here if I'm wrong, but if you leave out the pin, spring and mushroom, and just place back part 5 and 6, which by the looks of it are the Cap/adjustment screw and 6 being the o-ring seal,
Once you then hook it up to air (or use a blowgun is what I would do)
it should just run continuously.....
If so, the mushroom thingy is probably your problem, if not the blades (16) are stuck in the rotor (15), or you've got a blown seal somewhere.
Is the air coming out where it is supposed to be ?
If its not coming out of the normal exhaust area, it could be a blown/ leaking seal or O-ring.
I would wager a guess that to the right of the motor towards the head is probably ok, as in not seized, because you said you can turn the whatthjemacallit that goes in the socket by hand..

 

[Farmall450]

it is not an air tool oil from Marvel - it is Marvel Mystery oil - the stuff your Dad put in the crankcase back in the day - techs just accidentally discovered that it does great things for air tools #repurposed

So it quiets lifters and takes care of pneumatic tools, go to know.

 

[Josey Wales]

I tried the brake cleaner, nothing. I then took out (refer to above illustration) #5,6,7,&8. #8, in my tool is a rubbery, kinda plastic mushroom shaped thing. The stem on the mushroom seems to be on the spring and the ball, or cap of the mushroom is seperated. Could that be my problem? (It seems like it should be 1piece)

P.s. I've always used some kinda generic air tool oil, but I'll be sure to get some Marvel for future use.

Thanks!

I think it should be one piece as well. My CP 828 had the same issue (melted #8) except it wouldn't stop running.

 

[Reese]

I'm a new guy here, been lurking since earlier this year. I worked a few years years in the 80's at a tool shop. We would literally get buckets of trade in ratchets from the tool trucks to repair. The goal was to build as many good ratchets as possible from the pile of cast-offs. At one time I could blast through 10-20 per hour. There are only a few things that wear out on a ratchet.

A lot of air through the exhaust with a slow motor is either worn vanes or a loss of compression. The gear case (#24) in your illustration provides the compression and must be tight in the housing. We used superglue as a threadlocker and had a spanner wrench that fit the splines of the gear case we used to tighten the gear case. You can loosen the superglue by heating the housing with a propane torch.

A bad air valve normally leaks air through the exhaust all the time or gets soft and does not come off it's seat when the trigger is depressed.

If the motor is good and the ratchet is weak, you can restore the rachet by putting a wave washer between #37 and the top inside surface of the yoke #33.

Back in the day all the ratchets used the same or similar parts with the exception of a few odd ball Snap On ratchets.