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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: gus on June 02, 2012, 02:34:05 PM

Title: 4107 Radius Rods and Bushings
Post by: gus on June 02, 2012, 02:34:05 PM
Strangely enough I get no results when searching this subject, weird??

Question, do the newer plastic radius rod bushings install with the same home made tool as the old rubber ones?

If the new bolts I get don't have drilled heads how do you keep the two bolts holding the bushing washer from backing out?

I lost one on this last 3500 mi trip because the bolts backed out.
Title: Re: 4107 Radius Rods and Bushings
Post by: Ed Hackenbruch on June 02, 2012, 03:18:11 PM
On the one i had to replace this year, on my 5A, there is a little flat metal plate that the 2 bolts go thru, then you just bend up each end until it is against one side of the bolt head....that  is what keeps them from turning.
Title: Re: 4107 Radius Rods and Bushings
Post by: gus on June 02, 2012, 07:44:28 PM
Ed, that is a good system. Unfortunately GM didn't use it, they used drilled head bolts and wire. Problem is most replacement bolts don't have drilled heads and are grade 8. I've tried drilling grade 8 bolts and it is not a pleasant experience!

That bending plate has to be hard enough to hold bolt torque of 300 lb-ft and not break when bent so it is not easy to jerry-rig. I've seen them use on large end rod bolts but they usually have to be replaced because they break when pulled down for rod removal.

Lok-Tite may work but the threads have to be super clean, not easy in this case.
Title: Re: 4107 Radius Rods and Bushings
Post by: luvrbus on June 02, 2012, 08:21:13 PM
Flanged bolts with serrated heads work good they don't come loose fwiw I bought the safety wire bolts through Napa for a 4905 they were 5/8 or 3/4 I think they were about 6 bucks each for grade 8

good luck
Title: Re: 4107 Radius Rods and Bushings
Post by: chev49 on June 03, 2012, 01:30:43 AM
the fastener stores will have those bolts, but they wont be cheap of course.  two of them in town here. sometimes you gotta buy a whole box, but if you only need one, they often dont want to do the paperwork...
Title: Re: 4107 Radius Rods and Bushings
Post by: Runcutter on June 03, 2012, 07:35:20 AM
Gus, with Clifford's comment, I thought of a place here in Dallas where I've purchased some odd stuff.  Allied Bolt & Screw (now NAPPCO).  Looks like most of their locations are Texas.  If you go this route and they won't ship, I have a trip to Fayetteville in Mid-July (but that's 6 weeks from now) -- I could get them that far for you.

If the manual gives you size and thread count, this could be a way to go.

http://www.nappco.com/product.shtml#BOLTS (http://www.nappco.com/product.shtml#BOLTS)

Arthur
Title: Re: 4107 Radius Rods and Bushings
Post by: jjrbus on June 03, 2012, 08:04:51 AM
When I did my 5c a few of the metal plates (wish I had a picture) were rotted. I made a few of my own out of sheet metal. They are simply a piece of sheet metal, a couple holes to go over the bolts, with the ends bent up so the nuts cannot turn.

I do not remember the gauge or type of metal I used, maybe someone else will chip in.

Part #26!

http://www.mci102.com/PDF_Files/MCI%20102-Air%20bag%20parts%20pg%2012-201.pdf (http://www.mci102.com/PDF_Files/MCI%20102-Air%20bag%20parts%20pg%2012-201.pdf)                     HTH   JIm
Title: Re: 4107 Radius Rods and Bushings
Post by: gus on June 03, 2012, 12:43:29 PM
I can get all the parts, I just don't think I will get drilled head bolts when I order by part number.

Thanks for all the responses, Now on my other question, do the newer plastic radius rod bushings install with the same home made tool as the old rubber ones or do they require a different method?
Title: Re: Re: 4107 Radius Rods and Bushings
Post by: wildbob24 on June 03, 2012, 02:25:51 PM
Gus,

The nylon bushings consist of 2
pieces at each end. No special tool needed.

Bob

Sent from my SCH-S720C using Tapatalk 2
Title: Re: 4107 Radius Rods and Bushings
Post by: Runcutter on June 03, 2012, 05:31:15 PM
Gus, if the place in Dallas has the appropriate, drilled-head bolts, I could pick them up and ship them to you.  It's not far off my usual travel patterns.  If timing is important, I'm only in Dallas Monday and Tuesday this week (and, when I get back from this trip, I may have to do laundry and head out again to the other coast).  Just a thought, to make sure you get what you need.

Arthur
Title: Re: 4107 Radius Rods and Bushings
Post by: pabusnut on June 03, 2012, 05:44:34 PM
Guys, is this something I can do at home, like in the driveway?  I have a '73 4905.

Mine will need it eventually, as they are all cracked, but otherwise appear OK.   I have 4 air bags to replace on the front yet, but I eventually want to replace all the worn suspension items.   Is it something I can do one at a time, since it looks like each axle has 4 radius rods, which means 8 bushings, right?

Thanks!

Steve Toomey
PAbusnut
Title: Re: 4107 Radius Rods and Bushings
Post by: Charles in SC on June 03, 2012, 06:54:06 PM
Quote from: gus on June 03, 2012, 12:43:29 PM
I can get all the parts, I just don't think I will get drilled head bolts when I order by part number.

Thanks for all the responses, Now on my other question, do the newer plastic radius rod bushings install with the same home made tool as the old rubber ones or do they require a different method?

Gus, I replaced the ones on my 5303 a few years ago. I had a local shop remove them and then I used a hydrolic press I have (40 ton) to press out the old ones and press in the new ones. Then the shop put them back on. It was very straight forward without any thing that was high tech. If I did not have my own press I think any good machine shop could have done it. We reused the bolts which had self locking nuts.
Good luck.
Title: Re: 4107 Radius Rods and Bushings
Post by: gus on June 04, 2012, 09:00:51 PM
Arthur,

Thanks for the offer but I was able to order all the parts from OKC.

Turns out my parts guy has the older type rubber bushings so I'm in the process of making the special tool needed to fold them into the rod ends. I was surprised he had rubber but supposedly it gives a better ride than plastic. Anyway the tool is not too hard to make and simplifies installation. It folds up the bushing and it slips right in, really neat. I have a hyd press also but I don't think these rubber bushings can be pressed in, they are too soft.

He is also sending me studs instead of bolts, and metal plates to lock the nuts onto the studs instead of drilled bolt heads and wire. It remains to be seen how this works out since the original bolts are just barely long enough to begin to draw down the rubber bushing. I may have to use a longer bolt to draw it down then insert the studs. At least the locking plate will keep the nuts from ever backing off.

Now that I know the plastic is in two pieces I see why it either fell out or was ground off by the loose rod end. Supposedly the axle end won't come off unless the body end is removed.

I plan to do it in my back yard behind the shop where I have some gravel piled up to raise the bus off the ground. It must be high enough to crawl pretty far underneath and the suspension needs to be blocked in case the air bags deflate - needless to say.

Luckily mine is a lower rod, the upper rear body ends are a bear to reach, the bottom body end is bad enough but the axle ends are not bad. I think they may be a lot easier to access with the wheels and/or air bags off but not sure of that.

One question for you experts, why does the manual say to pry the axle rod end outward while tightening the bolts on the bushing washer? I cannot see the reasoning for this, it is too much for my limited brain. It amuses me that they call this thing a washer, it is 1/2" thick!!

Steve,

I'm not sure cracks are a problem. You will know for sure you have a problem when the bus pulls one way when accelerating and the other way when braking - it is very obvious and I knew right away what was wrong since I had the same problem on my 4104 but not as bad. I was very glad when I discovered it was a bottom axle end which can't come off unless the body end is off or very loose!
Title: Re: 4107 Radius Rods and Bushings
Post by: pabusnut on June 04, 2012, 09:40:27 PM
I don't have problems yet, but just don't like the look of the cracked rubber.  I do have some higher priority stuff, like the 4 front bags and the leveling valve.  Since I replaced the 4 bags on the back and the levelling valves, it never goes down! (except in the front!!!)

Steve Toomey
PAbusnut
Title: Re: 4107 Radius Rods and Bushings
Post by: Runcutter on June 05, 2012, 08:49:47 AM
Gus, glad you were able to find the right parts.  I was thinking that, with all the aviation maintenance that goes on in the Dallas area, there was a good chance of finding the drilled bolts here.  It sounds like you have things well in hand -- but I am also wondering how you draw up the bushing with short bolts.  It sounds like your thought makes sense.

Arthur
Title: Re: 4107 Radius Rods and Bushings
Post by: gus on June 05, 2012, 03:53:39 PM
Arthur,

Those short bolts may be the reason my supplier is sending studs, they can be longer than bolts and still allow drawing up the washer on the bushing without a longer bolt to get the bolts started.

The only reason I can see for bolts is to prevent mechanics from tightening the bushings too much. Bolts will bottom out in the threaded bushing pin before they compress the bushing too much.

One other thought, the bus has to be level and all suspension height distances correct before the bushing bolts/studs are completely tightened to prevent preloading the bushings in the wrong position. This would surely shorten the life of the bushings.
Title: Re: 4107 Radius Rods and Bushings
Post by: Len Silva on June 05, 2012, 04:16:11 PM
While you are going through all that work, don't forget the ones in the back.  They can make a tremendous difference in handling.
Title: Re: 4107 Radius Rods and Bushings
Post by: gus on June 06, 2012, 06:06:48 PM
Len,

The rear right lower rod is the one I'm repairing.