1/2 shaft u-joint

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paracord
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1/2 shaft u-joint

Unread post by paracord » August 23rd, 2017, 4:09 am

Tried to grease a u-joints on the axle shafts and wouldn't take. None of them would take grease. So I thought dried old grease in passages possible in one but not eight. Took one apart and grease looked fine ,then I pushed a drift through passage to clear it and it stopped so I hit lightly with a hammer and out comes 2 plastic inserts. Did the other passage and out comes 2 more plastic inserts. Took all my u-joints apart and every one had the inserts in them. Total of 4 plastic plugs in each joint. Can anyone explain to me why they put these inserts in a u-joint? Surly it's not To keep from over greasing? Now I can grease all my joints as you should be able to.

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muttguru
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Re: 1/2 shaft u-joint

Unread post by muttguru » August 23rd, 2017, 5:14 am

paracord wrote:......... I hit lightly with a hammer and out comes 2 plastic inserts. Did the other passage and out comes 2 more plastic inserts. Took all my u-joints apart and every one had the inserts in them. Total of 4 plastic plugs in each joint. Can anyone explain to me why they put these inserts in a u-joint? Surly it's not To keep from over greasing? Now I can grease all my joints as you should be able to.
Yes....they are "grease restrictors" and they were installed on some, not all, of the half-shaft u-joints. When you've cleaned out the grease channels that run through the cross, re-grease the joint and put the restrictors back in place.

Most important is to use the correct grease gun... one with a needle-nosed adapter. Like this one.....

Image

Ken
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Ken

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paracord
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Re: 1/2 shaft u-joint

Unread post by paracord » August 23rd, 2017, 6:30 am

So that adapter will make greasing the driveshaft u-joints easier? I have no problem with the axle shafts. I've never seen one before.

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rickf
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Re: 1/2 shaft u-joint

Unread post by rickf » August 23rd, 2017, 8:38 am

Ken, I am curious about the "restrictors. What is their purpose? I have never run into them in the many hundreds of u-joints I have dealt with. And on the needle greaser, you will need one to get the fittings on the outer axle joints especially. I prefer the one that screws onto the grease gun. I have one like in the picture but you have to hold it for the most part and then pump the gun plus push against the joint to seal it. Very messy at best.
1964 M151A1
1984 M1008
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paracord
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Re: 1/2 shaft u-joint

Unread post by paracord » August 23rd, 2017, 9:52 am

Rick I have no problem greasing any of my outer u-joints. The zerk's are facing inwards and the coupler fits right on with no problems.

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muttguru
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Re: 1/2 shaft u-joint

Unread post by muttguru » August 23rd, 2017, 9:59 am

rickf wrote:Ken, I am curious about the "restrictors. What is their purpose? I have never run into them in the many hundreds of u-joints I have dealt with. And on the needle greaser, you will need one to get the fittings on the outer axle joints especially. I prefer the one that screws onto the grease gun. I have one like in the picture but you have to hold it for the most part and then pump the gun plus push against the joint to seal it. Very messy at best.
Ahhhh.....

I was mystified when I first lubed the joints off the vehicle and wondered what those black plastic plugs were.

It's in the TM..... have a look at TM9-2320-218-20-2 dated May 1982. Section 6-5, Page 6-6, Step 10.

No charge for this advice...... :D

Ken
Kind regards....
Ken

Always wanted - Details and pictures of M416 Trailer data plates & M151 data plates & body-tags for my research. Thanks!

Contact address - - muttguru@aol.com

Note for 2023..... Ken..."Less Stress - More Exercise!"

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m3a1
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Re: 1/2 shaft u-joint

Unread post by m3a1 » August 23rd, 2017, 11:37 am

Grease is going to seek the path of least resistance. When lubing u-joints off the vehicle I've always left the caps on, lightly clamped them in place ensuring even back pressure across the cruciform passage and that was that. In doing so, you also get the benefit of having well-lubed caps.

And I'm going to go out on a limb and post the following, just in case some folks aren't aware.... The delivery end of most grease guns is adjustable, allowing it to fit many different sizes of grease fittings. If yours keeps popping off or grease is oozing out while you're pumping, give the end a twist - righty-tighty. If it pops on the fitting snugly, you're there. If not, adjust it. And do I need to add, giving that old grease fitting a quick wipe before attempting to lube it is important too. As your momma told you, "Cleanliness is next to Godliness."

If you followed the thread on my truck, you may recall that I encountered a (made-on-a-Friday-at-quitting-time) u joint that had not been drilled so that grease could pass through the fitting into the cruciform. There's a lot of weird stuff out there, kiddies.

Cheers,
TJ

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