Frustrating 809-series sprag!

[Floridianson]

Guess there are two sprag problems. One it won't engage. Two locked in forward or reverse sprag.
I had my bob at the mud pit Sat and was doing some stupid stuff (normal for me ) and I hopped the truck four different times for about a min. trying to pull someone out. When I say hopped I mean all four wheels off the ground and spinning on the Gov. and digging four deep holes.
Well something gave and if I went from forward to reverse I could now feel a small lag in the transfer case when I went forward. I was not real worried about it and when I get the truck home I guess I will find out what I broke and fix. (no problem when you got the parst and stuff right)
I went to leave the mud pit and hit the road and can you say bunny hopp.
I mean she was a hopping. Well I knew what I did and tryed to roll froward on a hill in reverse and no luck. I tryed rolling backwards in first gear and still locked. Me being stuborn I pushed her homeward and had to leave it in low range fourth as the bind on the sprag was like a brake being put on in the transfer. The house was only five miles and If it brakes then I I will fix but I'm gettin home. Two miles down the road and going slow so as not to hopp just in a bind I got pissed off and saw the grass shoulder was flat and comming up. I hit the grass at 25 mph and slamed on the brakes and heard a clunk in the transfer case. Well it poped out of what ever sprag it was in and drove home fine. I have not check to see if there is ingagement yet as I am still washing it but I had to wear the sprag down some. Guess I will swap out transfer cases and take that one apart sometime to see dammage.

 

[atvcat33]

why cant you take a air valve like on a duece and put it on the air lines supplying the poppet assy so then you can shift on the fly, or will that screw something up, on my 818 the truck would jerk crazy in 1st through 3rd the sprag was like tring to engage and make a crazy clank and would jerk the wheel left or right and would stop, so i just pulled the driveshaft all together, you can buy the new poppet assy for 250.00 but seems $$$ just my two cents

 

[73m819]

yes, the deuce air switch, is the thing to use for this mwo field mod

 

[sandcobra164]

Renewing an old thread as it was most useful to me. I have a M818 that was experiencing sprag problems. Most notably, every now and then it'd feel like a axle had dropped out from under it accompanied by a loud bang. Each time the axle was still under there and nothing appeared broken. One thing I'd always noted about this truck is how I never heard the usual venting sound when going into reverse or back into neutral. Well the truck is rarely driven anyways and it has a few other items that need looking into. I started working on that list today and the first thing I went after was the sprag actuator. I've done this many times on National Guard M809 series trucks, pull the lines on the driver's side of the tranny and spray a healthy dose of PB Blaster into them, reconnect, start the truck, build air and rock from neutral to reverse till that healthy clunk and psst sound come back to life. NO GO on this truck. I took the tranny tunnel cover off and on the passenger side I notice a dang bolt threaded into the T that goes between the two air valves on the side of the transmission. It couldn't vent the air from either side of the air piston in the Sprag actuator. I pulled the bolt out and Presto, a quick clunk and psst each time I shifted from Reverse to Neutral and back to Reverse. Why would a bolt be in there in the first place? I've never really paid attention, I'm sure a breather should screw into that T to keep dirt out but for now, it's open and shifting like a champ.

 

[quickfarms]

Interesting some private put a bolt in the hole. I thought most breathers were pipe thread.

 

[doghead]

The exhaust vent is usually left open.

I've seen worse. Most of the time is simply does not make sense what was done.

 

[ke5eua]

yes, the deuce air switch, is the thing to use for this mwo field mod

Sorry to dig up an old thread, but I have been trying to find this switch and have come up empty handed. Any suggestions on where to find one?

 

[doghead]

Google search, "air toggle valve". http://www.buyersproducts.com/Pneumatics/Universal-3-Way-Toggle/Toggle-Air-Valve-w-Faceplate/4793/

Any truck shop should have them.