Broken grease zerk on slip yoke

[tucsonjwt]

My 83 C20 has a sheared off grease zerk on the slip yoke behind the center carrier. This appears to be a welded on zerk, not a threaded in one, so there is no option to just unscrew it and install a new one.

Does anybody have a fix for this? If there is no fix, should I just wait for it to seize up and then buy a new one, or should I buy a new one now? Where would I find a new one?

[68Timber]

Can you tap the hole and install a threaded zerk fitting?

[tucsonjwt]

I thought about that, but it seems like you would introduce metal shavings into the yoke. I never had one apart to look inside, so I don't know if it is completely hollow and really "cleanable."

Here is a pic. I think the mechanic who replaced the clutch let the driveshaft hit the concrete and broke it - but that is just a theory, since that is the only work I had done on the truck since last year when I greased the yoke last.

[Jeff's bowtie's]

Unscrew the tin collar off and pull the slip yoke off drill it and tap it out replace with new grease zirk and flush the inside out with parts cleaner

[bilfman]

Load up your drill bit with grease , it will capture most of the shavings.

[bonehead]

Use a left-handed drill bit greased up to catch the shavings, drill it dead center. A lot of times the broken zirk will back right out as you drill. if not retap it and install a new zirk

[68Timber]

Nothing wrong with blowing it apart to drill and tap if you don't mind the labor but I'd be comfortable greasing up a drill bit as others suggested.

[tucsonjwt]

Thanks for the tips. Upon further cleaning, it looks like the driveshaft let loose on the road - probably while the clutch mechanic was test driving it after repair. My guess is that the center carrier was not secured and broke loose. So, I probably have spline damage which is unseen. The new pic shows that the yoke was clearly dragging on the ground.

[tucsonjwt]

So, any thoughts on how long this yoke will survive without new grease? I suspect that if I pull it apart the spline will show so much damage that it will need to be replaced. I wonder of the damaged spline will ruin the mating female part on the end of the front section of driveshaft - if it has not already ruined it.

[68Timber]

If you're concerned that it's junked, I'd pull it and take it to a driveline shop and let them give it the once over. It'd probably be fine with a new zerk fitting and getting balanced.

[tucsonjwt]

After further consideration, I don't think the zerk can be replaced. If I drilled out the existing zerk enough to install an new zerk, I would be left with a hole on a round surface which really can't accept a zerk thread. I would need some sort of square and flat boss to get a flat surface to drill through.

[TrailerTrash]

Just an idea that I would try.
grind it flush with the shaft. use a center punch to make a dimple. use a small drill bit to make a hole. then use an easy out.

it might not work I know how things like this go.

but as said above if you are worried about damage then the best thing to do would be to take it to a shop and get it checked out

let us know how how it turns out man

[tucsonjwt]

That is what I was thinking. The "grind it flush with the shaft" part that concerns me. If I get a flat surface flush with the round shaft and get a hole sufficient to accommodate a new grease zerk, I think that would get me down to a round surface again.

I emailed a local driveline shop to get their advice and find out if these yokes are still available and whether I should drive it until the thing seizes up. I have greased the thing every year so it does have grease in it, and I only drive less than 1000 miles per year.

[hatzie]

The broken Zerk should already have a hole dead center. The metal you see is from the threads unwinding like a slinky then bending over the grease hole... or just good old fashioned crud

.
Use a LH drill bit. It'll likely back right out of the shaft. Then thread a new one in.

If the shaft got dragged on the ground the tin cap would be beat to death and the abraded portion would not be nice and neat like you have there. The carrier bearing retainer would be beat to heck too. It looks like someone had the same issue as you did and got a little ham handed with an angle grinder or the last balancing job included removing a small amount of material from the shaft in that location.

I've had gators and other low lying road trash on the interstate biff that zerk off the shaft, more than once, when I couldn't change lanes to avoid em.

You're spending a bunch of time worrying about what could be wrong. That's counterproductive. Take the prop shaft off and pull it apart. If it's fouled up it ain't gonna get any better while you worry about it. If it's fine, and I suspect it is, you can drill the damaged Zerk with a LH spiral drill bit and replace it. It'll likely back right out with the drill because it's soaked in grease.

[Nessmuk]

You can't get grease in it with one of the ends in a harbor freight grease gun adapter kit? I get a fair bit of use from mine.

[tucsonjwt]

The picture does not show the zerk very well. The zerk was in perfect condition last year (prior to clutch replacement) and I grease the chassis myself (including this zerk) every year. There is no hole left in the zerk - the zerk is completely ground shut - so no opportunity to use this zerk anymore to grease the yoke. (I suppose I could grind it off, drill a center hole, and use a needle pin style grease fitting for my grease gun, but I hate using those things - they always just seem to spit grease back out at me.)

I got a nice email response from a driveline shop in town I have used in the past. The tech who responded said (as I suspected) that the yoke should be removed to inspect for spline damage. If the spline is OK, then he says he can replace the zerk (but I asked him how he would get a conventional square bottom threaded zerk in there.) He said many of these old yokes are discontinued parts, and C20s used about 5 different styles of yokes. He may have a used yoke that would work, or may still be able to get a new one. I am waiting to get an estimate for the inspection/repair at his shop.

Abrasion on the cap and in front of the zerk indicates to me that it was dragged on the ground - it is all perfectly lined up - although I suspect that it was a "light hit" as they say in the salvage yard business.

We do not have gators in this part of the desert, but it might have been a chupacabra. I never drive this truck out of the city so a significant road debris impact is not likely.

Thanks for all of the input. I am not worried - just trying to get as much data as possible prior to taking it in for a wallet flush at another mechanic.

[hatzie]

Gator is a slang term for the dually casings left behind big trucks...