NPT or Zerk?

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NAM VET
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NPT or Zerk?

Post by NAM VET »

recently saw a pic and post where a forum member (I can't find it now) had a pic of the lower four bolt plate on his steering knuckles, where he had installed a Zerik, after finding inside and above the plate rust and water. So I am wondering if it would be best to drill a hole for an NPT plug in the plate, allowing oil and whatever is in there to be pushed out with greasing from the top Zerk, then reinstalling the NPT plug. Or... should I drill and install a Zerk, allowing greasing from below as well as above. Not sure it makes much difference, and I don't drive under water, but I would appreciate your collective opinion on this. Thanks, NV
Cal_Gary
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Re: NPT or Zerk?

Post by Cal_Gary »

Some may have other thoughts but I don't know if that is necessary Hal.
The lower part of the half-cone (for lack of a better word) has a slotted-head plug that's removed when greasing the upper zerks. You know it's full when grease starts coming out the hole (and remember to reinstall the plug afterward).
Just my 2 cents,
Gary
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Re: NPT or Zerk?

Post by John Mc »

Thanks, Gary. I was not aware of that plug.
1951 M37 "Brutus" w/Winch and 251 engine
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Re: NPT or Zerk?

Post by NAM VET »

I thought there was some "plug" somewhere, but have never been able to find it. I will find it today, and try to take a picture if I can. Thanks NV
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Re: NPT or Zerk?

Post by John Mc »

I just swung by Tim Holloway's shop to take a look at this - turns out he is just finishing up working on my front end. He has them most of the way back together. Unfortunately, I did not think to take a picture.
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Re: NPT or Zerk?

Post by NAM VET »

here it is, took almost a whole tube of grease to fill both sides. Thanks for the suggestions on where to look. NV
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Re: NPT or Zerk?

Post by 06boblee »

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This is what I found when I opened up my knuckles--they were full of grease, but not at the bottom. The bearings were completly rusted up.
So, I put in a grease fitting so that I could flush the bottom bearing. A NPT plug might work, but I prefer to fill the bearings with new clean grease, not pumping the old dirty grease thru them.
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Re: NPT or Zerk?

Post by John Mc »

Tim told me he removes the top grease zerk and puts in in the plug hole, then pumps until the grease comes out the top hole. (Then switches things back when done - you don;t want to leave the zerk in the plug hole.)
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Re: NPT or Zerk?

Post by NAM VET »

I think I will remove the bottom plates later this summer and check the innards out. Grease is cheap. The "old" grease that come out of the screw NPT was not grimy or watery.

Glad we are all here helping each other stay on the road. NV
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Re: NPT or Zerk?

Post by Cal_Gary »

Great insights Everyone-well done!
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Re: NPT or Zerk?

Post by NAM VET »

As we talk and work and ponder how to keep our trucks running, often making them in our opinion and efforts better than Dodge and the Army did when they designed and contracted for them, I sometimes reflect that the men who made them and the military who bought them didn't concern themselves with making them so 60 or 70 years later they would still be out somewhere driving and working hither and yon. We do that, however we can. My own M37 (42) was built in 1952. Going back from that date 70 years is 1882, long before cars even existed. Just a reflection with my morning coffee and a big helping of my wife's Lemon Cake.

Keep it up, guys. Hal Copple, aka NAM VET, in UpState SC
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Re: NPT or Zerk?

Post by sturmtyger380 »

Going back from that date 70 years is 1882
That makes me think of the wooden cargo delivery wagon some of my family has in storage. It's from an old country store in the next county over. Still has the original paint and name on the sides. I would say it's from the early 1900's.

If we were to try and play with it we would have to find horses and all the rigging. I think I will stick with my M37. :D
47 CJ2A
53 M38A1
52 M37
51 M38
67 M416
?? M101A1
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