M38 - Nothing at all to do with M151s

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fergrn37
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Re: M38 - Nothing at all to do with M151s

Unread post by fergrn37 » October 3rd, 2017, 10:42 am

First world problems.....
Some people are too busy knowing it all to ever learn anything

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m3a1
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Re: M38 - Nothing at all to do with M151s

Unread post by m3a1 » October 3rd, 2017, 4:27 pm

Yeah, I suppose. Aside from a car battery taking a dump in my M151, I got it made in the shade. 8)

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Re: M38 - Nothing at all to do with M151s

Unread post by rickf » October 3rd, 2017, 6:24 pm

If you send a PM to Raymond on here he may be able to give you some insight and or pictures on those things, His family has been in the gas and oil business for many years/generations.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: M38 - Nothing at all to do with M151s

Unread post by rickf » October 3rd, 2017, 6:25 pm

What, no massive Halloween undertaking this year?
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: M38 - Nothing at all to do with M151s

Unread post by m3a1 » October 23rd, 2017, 7:22 pm

Well, as you can see....this Halloween is getting out of control. It's kinda weird coming around to the front of the house and finding strangers in my yard snapping pictures. :lol: :lol: :lol:

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Re: M38 - Nothing at all to do with M151s

Unread post by rickf » October 23rd, 2017, 7:53 pm

I had faith in you. :twisted: :twisted: :mrgreen: :mrgreen: :mrgreen:
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: M38 - Nothing at all to do with M151s

Unread post by m3a1 » October 29th, 2017, 11:23 am

So, with Halloween and other end-of-year distractions winding down I'm finally getting back to the Jeep and other things. Even the MUTT has had to wait. We have the many miscellaneous parts for the steering knuckles cleaned, inspected, de-burred, blasted, primed and painted and many more new parts on the way from what is hopefully my final order for a while.

I elected to replace the right steering knuckle housing altogether, rather than helicoil the lone wallowed out bolt-hole because the helicoil kit was about $30 and the new casting was only $59. Remember, I always think about the survivability of my work in the long run...like, how will the work I've done be viewed another 60 years down the road. If I've done the job right, they may not even realize I've been involved. Anyway, the old steering knuckle casting may end up on eBay (vastly discounted and with full disclosure, of course) or it may simply end up hanging here around as a trophy.

As a salutary comment to bringing the front/rear axle and brakes back up to spec, all tallied it has been VERY expensive primarily because these Jeeps can be kept going for a very long time, despite lots of abuse and neglect, before they just won't go anymore, which leaves the guy who picks it up from there left holding the bag, so to speak......and that is something anyone should consider when attempting to resurrect any tired and worn out truck. These parts aren't necessarily all that expensive in dribs and drabs but when you have a truck that needs one (or four) of everything, the numbers and and do add up very quickly.

I think I have most of the bases covered, so soon we will do our parts layout and see what's missing before diving back in.

Cheers,
TJ

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Re: M38 - Nothing at all to do with M151s

Unread post by rickf » October 29th, 2017, 11:55 am

So how much does the boy owe you so far? Reality check!!!
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: M38 - Nothing at all to do with M151s

Unread post by m3a1 » November 11th, 2017, 8:25 pm

Well, at long last I've managed to get back to this project. I did get quite a few things sand blasted and and painted. I ended up ordering a completely new hub for the left side as one of the drive flange bolts had broken off and the bolt hole was also wallowed out. Because of this I found I had only half of the bearings and races I needed today, so I got over to O-Reilly's Auto Parts just in time to get another couple of sets added to their afternoon parts run and had them in my hands in a hour. Having to step away from these jobs for a time really throws me off my game!

What you see here is my solution to getting the races pressed down deep into these hubs. I lubed the throat of the hub and stacked the old races (which is why I don't throw anything away until the job is done) and I used them as spacers to press the new race down until it was seated. Afterwards, I simply tapped the old bearing race out with a brass punch. If you do this, make sure the bearing races are stacked back to front so that there is a surface to strike against when it's time to tap them out. Granted, it's a little awkward-looking but I didn't have the proper tool for seating the new races and elected to use what I had on hand which is perfectly acceptable.

This is a also a good side-by-side photo of how bad the old races were, as compared to the new ones.

The front side of the hub has a relieved area all the way down to the edge of the seat for the bearing race so those old bearing races simply come right out without any effort. However, the back side is an interference fit all the way down.

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Last edited by m3a1 on April 13th, 2018, 1:06 pm, edited 2 times in total.

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Re: M38 - Nothing at all to do with M151s

Unread post by m3a1 » November 27th, 2017, 9:31 am

So, along the way I'm getting more odds and ends into the blast cabinet. I think I've already mentioned that there's a ton of Bondo in this truck. There was even bondo on the headlight bezels! I spent some time hammering this one out before cleaning it up. It's not perfect but it's close enough. Some of these irregularities are part of the character of the truck. I might just as easily have procured some new ones since they are inexpensive and they are the same bezels as used on most any M-series vehicle but, I just couldn't refuse the challenge.

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I got this backing plate all pretty and it fell off the hook and down into the gravel. (Don't ask me how, because I don't know.) Naturally, it did it while the paint was wet. :roll: I just hung it back up and let it dry and then brushed the junk off, did a light sanding on the messed up areas and then touched it up.

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Last edited by m3a1 on April 15th, 2018, 7:17 pm, edited 3 times in total.

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Re: M38 - Nothing at all to do with M151s

Unread post by rickf » November 27th, 2017, 12:38 pm

Well. I guess it is time to rent an excavator and clean out all the crap out of there and put in a concrete floor! Then you can cover it back up with all the crap again but at least it will be clean crap then. :lol: :lol: :lol:
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: M38 - Nothing at all to do with M151s

Unread post by m3a1 » March 29th, 2018, 9:06 pm

Well, at long last, I'm officially back at the M38. My last real efforts were back in November which is, ummm....oh SNAP!....five or six months ago!

Spent the day cleaning rust off of exposed metal surfaces of parts that had formerly been perfect. Hopefully, tomorrow I'll have the old girl back on all fours.

Cheers,
TJ
Last edited by m3a1 on April 14th, 2018, 11:38 am, edited 2 times in total.

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Re: M38 - Nothing at all to do with M151s

Unread post by fergrn37 » March 30th, 2018, 10:00 am

That fire extinguisher you have hanging on the post is under a recall. Go to Kidde and get it replaced for free.

http://www.kidde.com/home-safety/en/us/ ... inguisher/
Some people are too busy knowing it all to ever learn anything

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Re: M38 - Nothing at all to do with M151s

Unread post by m3a1 » March 30th, 2018, 1:32 pm

Nope.. It's not. I already checked. I wish it was. I like getting new stuff for free! :lol:

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Re: M38 - Nothing at all to do with M151s

Unread post by m3a1 » March 30th, 2018, 3:07 pm

Ok, here we go! Started today with a review of my TM over coffee. Part of this image is cut off. Click on it if you want to read it. The reason I have posted this is to indicate the shim pack we'll be starting with. 30 + 10 + 5 + 3 = 48 (thousandths). Let's just call it 48 because if you're like me, when you start hearing "thousandths" your eyes start to glaze over. 48 is good enough for this discussion. In my case, I started with shims amounting to two 10s and nine 3s for a total of 47. I ordered a set of shims and they gave me a whole bunch of 3s which is perfectly OK because we will be taking away or replacing shims until we reach the desired results.

The purpose of these shims is to act as spacing. Their presence under the TOP steering knuckle flange cap (and only the top cap on the M38) creates a specific distance between the inner faces of the steering knuckle flange caps and these caps not only serve to create a fixed point upon which each kingpin bearing cone will live relative to the steering knuckle, but also exert a certain amount of pressure through those bearings and onto the bearing race which is situated on the cup at the end of the axle tube. That pressure is a farmboy's way of describing "pre-load". The fewer shims, the shorter the distance between the top and bottom steering knuckle flange caps and the result is more bearing pre-load exerted upon the bearing cones and onto the bearing race.

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Here is the foundation we are going to be building upon today. Clean, free of debris, and about to have new bearing races installed and seated fully. Free of debris means entirely free of debris, grease, anything that takes up an appreciable amount of space. If there's junk in the bottom of the recesses for the bearing races you cannot get them fully seated and that will affect everything because we are talking about adjusting pre-load by taking out shims measured in very minute amounts (thousandths) so, take whatever time it takes to get this bit clean. This is the first big trap when renewing this part of an old Jeep. Have it clean and have those bearing races seated fully and you'll be A-OK.

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Shims, and lots of them! I started out with a micrometer then went to a feeler gauge, laying it and each shim side by side and ran a fingernail across the joint. I quickly found out most all of these were 3s. The 10s are obviously thicker and easy to spot.

When you are working with these, don't get too hung up on what is what thickness. This is not rocket science. It is the result that counts and the acceptable range for the pre-load upon the king pin bearings is very broad and ultimately, a matter of what your preference is. Our simple goal will be to end up in the acceptable range AND with equal pre-load on both sides. However, equal pre-load is not necessarily established by using the exact same number and size of shims on both sides, particularly when we are working on an older vehicle which has had who-knows-what done to it. You may recall, I've replaced a steering knuckle casting on one side so there's one possibility for variance right there.

Green twist ties tell me I have established two matching shim packs to begin working with; one for each side.

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Here is the brake hose guard shown in profile. This goes on top of the top steering knuckle flange with the sloping bit toward the center of the vehicle. Only two bolts pass through this guard. I want to revisit this right now because it is VERY important. The TM is in ERROR on the matter of which bolts are used to secure this guard. You MUST use the LONGER bolts to secure it. You must NOT use the longer bolts in any other position other than the brake hose guard. If you are just coming into this here and now, read my earlier, more detailed posts on the matter. In this photo you can see that one part of the guard is almost twice as thick as the other owing to the manner of its construction. Make up the difference by putting a flat washer on the bolt holding the single-thickness side.

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Take note - here you will see I have installed the hose guard 180 degrees out of phase with the way it should be! DUH! :roll: This is what happens when I'm not being paid for my time! :lol: :lol:

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Hardware, bagged and sorted and one or two new bolts to replace those that were stretched. All of these have brand new lock-washers. New hardware is cheap. Get some!

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Here's the morning layout of parts in a logical fashion. Trouble is lurking in one of those 11590 bearing boxes because some nitwit returned parts and probably thought it would be cute to put a bearing race in a bearing box. Yes, I bought these from a reputable supplier whose reputation also got damaged because they didn't check it either. Finally, I got screwed when they shipped this to me (and charged me for it). So, here I am, all ready to get to work and I'm missing one @#$%&* bearing! The lesson here is a simple one. When you receive the parts you ordered, open EVERYTHING and check. Not catching this earlier is MY fault and this screw-up cost me $20 and several hours to source a replacement locally.

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Ok, my bad. In this photo, I've got the top bearing flipped over and facing the wrong way but you should still be able to get the point. Everything you see here (and more) is suspended upon that nice shiny cup at the end of the axle tube by means of these two tiny little bearing cones and nothing more. Getting through all the banging and bashing that these vehicles endure depends upon two little conical bearings. So, the next time you're watching a video of guys enjoying their flat fender jeeps on the rocks at Moab, or an old clip of the U.S. Army guys boinking over a test track in a Jeep, think of the tremendous stresses that can be exerted upon a well-engineered (and yet very small) collection of metal parts.

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Here's a shot of the top assembled without shims but without each bolt tightened down. IF everything were tightened down and IF all the bolts were in the right places and IF there were NO shims in place, you would see 1-1/2 turns of thread protruding past the inside face of the steering knuckle and guess what...a shim pack valued at 48 just happens to be about equal to 1-1/2 turns of thread. Starting to make sense?

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Ok, so I chased out all the bolt holes with a tap yesterday. This bolt was offering some resistance and you can see why. Trouble in the first four turns of thread and arguably as many as 13 turns. This is one of those jobs where getting the correct preload is a matter of assembling and disassembling many, many times. Having bolts and bolt holes that are true and correct is a HUGE bonus and makes a tedious job ever so much easier.

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Here's a photo of shims in place with the shims oriented in such a way that I can pluck the skinny shims off with ease while we sneak up on a proper pre-load.

The matter of finding the correct number of shims to establish proper pre-load goes like this -

1. WITHOUT making any installation of the oil seals and WITHOUT packing the bearings, install your steering knuckle and it's bearings in its entirety.
2. Install the bottom steering knuckle flange caps and torque them to spec (I am using 30 lb-ft of torque and will wrap everything up with 35). The bottom steering knuckle flange will remain in place and undisturbed throughout this process.
3. Install your complete top assembly with hose guard (and that extra flat washer) and your shims. The top will be where all the adjusting takes place.
4. While you are going through the process of working out just how many shims you need to remove, tighten the top bolts down to snug, rather than to specifications. It is quicker, easier and will help speed you through the process of getting close to that optimal pre-load.
5. Make your checks for adequate pre-load, disassembling and taking away shims, then reassembling and rechecking until you are getting in the ball park. But, while you are doing this, remember that proper torque will add substantially to the final pre-load.
6. When you begin to feel your are getting close, you can start checking with properly torqued bolts.

What is adequate preload and how do we check for it? The TM calls for 6-9 pounds of pull checked at the hole for the tie-rod end. This pounds of pull is for where the steering knuckle just begins to move, not during movement. There are lots of fancy pull-scales for this purpose. I used an antique scale from the turn of the century. Whatever you use, use the same device on both sides.

Generally speaking, if you are moving a properly pre-loaded steering knuckle by hand (one that does not have its grease seals or anything else installed, you will find that it is mildly stiff and pivots with some resistance. What you do NOT want is a steering knuckle that pivots in the breeze. The mechanical advantage provided by the rest of your steering (such as the steering box and the leverage of the bell crank) balances against the resistance achieved by proper pre-load. That is why we are going to all the trouble of getting this right. It will pay huge dividends when it comes to enjoying the truck. Any prospective buyer will be seeing a lot of value when he test drives your truck and finds the steering to be smooth and responsive because as we know, these old flat fenders are notorious for having sketchy steering. Getting this job right is a bedrock principle to having good steering.

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When you've determined the proper number of shims to get that steering knuckle moving with the resistance you find acceptable, remove everything and double check your bearings, ensuring there is no damage from all this fiddling around. I know what you're going to ask. What was my final total shim thickness? Well, I'm not going to tell you but is was far, far less than 48 thousandths. I watched a very reliable source on YouTube do one that required NO shims! So there can be some very substantial differences between trucks. How many attempts before I got to where I was happy with the results? Nine times on the right side where I started and eight on the left. Seems like a lot, but good prep makes it far easier.

My best advice? If you get into one of these, follow the steps until you get things the way you want them to be and so long as both sides are mildly stiff and match reasonably well. If you do that, you will have good results.

In this photo, you can see one of the reasons we don't do this job with packed bearings. See all the junk that migrated down onto it while I was futzing around with shims? Flecks of paint and whatnot, all of which need to be removed before final assembly.

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Checking the new grease seal for fit. So much easier to confirm fit on the work bench rather than to having to struggle with it while it's mounted on the truck. That shiny surface needs to be painted! Since I'm waiting for another bearing to be brought up, I'll use that time to get them coated.

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Checking the felt sweeper to ensure those bolt holes line up.

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Checking the retaining plates to ensure their bolt holes line up.

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Cleaned up the original hardware for the seal kits and the identifier for the steering axle joint.

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Prep for final installation. The felt sweeper goes on, over the cup and then the rubber grease seal (which is a split ring). Gentle pressure will allow you to work the split open end over the axle tube. DON'T bend it - just flex it. When the steering knuckle is in place, work the grease seal into place much as you would put a tire on a rim. Work it around until it all fits. If you took the time to fit it on the work bench this is a relatively easy task. However, if it still doesn't fit you may have to trim the ends where they meet at the split. Keep the split in the grease seal at the top, 12 o'clock position. Then, lay the felt sweeper over the rubber grease seal and the retainer over that and run your retaining bolts in, finger tight.

The felt wiper doesn't need to be oiled, though I suppose you could put some silicone on it. The bottom line is, don't put anything on your felt that will attract or hold dirt. I elected to install mine dry.

Do not over-tighten the retaining bolts for the seal retainer. Don't tighten to the point where you deform the retainer. Run them in equally. You will be able to see the threads as they protrude through the casting and in this way, judge how equal your bolts have been drawn down.

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Finally, all back together (brake hose guard facing the correct direction :wink: ). You will recall that the TM instructs us to set our pre-load without the grease seal installed. Here's a problem I may be facing and a question I do not yet have an answer to. These are a new-style civilian grease seal being put to work on a very old military truck. With these new style seals installed, the energy necessary to swivel the steering knuckle is roughly 33% more than without them installed and I don't know what is "normal" for these so I intend to just roll with it as the steering knuckles are still moving in what I would characterize as the high side of the mildly stiff, rather than really stiff. But my original pre-load is right so I really have very little to worry about. Perhaps with some metal preservative (silicone) on the cup, the grease seals will start moving more easily across the surface of the cup.

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Look at that glaringly white felt! I would have preferred they would have made these felt sweepers from a darker material!

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Hope someone finds this useful.
Cheers,
TJ
Last edited by m3a1 on April 15th, 2018, 7:18 pm, edited 7 times in total.

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