Broken rear upper shock mount:updated

[vdubyah73]

Bummer. It was broken before. The bolt was snapped off in the blind nut and turned around and just welded to the outer piece the weld let go as soon as I drove it for the first time. Lousy weld. Rewelded it, it lasted 5 monthes and tore the outer piece of steel off the mount! this is a good thing cause now I see whats going on and how to fix it stronger.

Ok the question, Took the shock out and I still have a bang thump on just right bumps. What else could be thumping back there, on the same side. Couldn't look yesterday it was blowing and raining, couldn't look today, I was laying tile in the back of the Bus. Gotta keep my priorities straight ya know.

Going under it tomorrow after work any ideas on what to look for banging around back there.

Bill

[Amskeptic]

any ideas on what to look for banging around back there.

Bill

Banging around with shock entirely removed?
Check diagonal arm bushings, bolts holding diagonal arm to spring plate/wheel carrier, and look for any evidence that parts have shifted against each other. Then get the crossbar jack out of the spare tire well and the metal wheel chock out from under the rear seat.
Colin

[vdubyah73]

Still haven't figured out what else is banging around around . Tomorrow I'm going under da Bus to fabricate a new shock mount useing whats left of the old and that piece of steel used for capping lally columns. Not sure yet how I'm gonna deal with the broken piece of the bolt left in the original nut. Prolly try to get it out first and use the original nut. If not I'll drill it out completely and weld a new one in.

Bill

[Amskeptic]

Still haven't figured out what else is banging around around .

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use the original nut. If not I'll drill it out completely and weld a new one in.

First option would be a lot easier, no? How accessible is the area for welding in a new one?
Colin

[vdubyah73]

Looked around underneath didn't find anything except maybe shift coupler or homemade heater "y" pipe may be banging around. Not enough room to get a mig in there even with a couple inches of the outer skin removed. The nut sits inside a piece of channel steel about 2" or so wide and deep. So I drilled it out, completely obliterated the old threads so now it's tapped to 1/2"- 20 threads, had to ream out the shock to accept the 1/2" bolt. If I ever sell it the next person to change shocks will be on here talking about the po hack repairs My mig shat the bed today need a new liner for the gun the wire binds and won't feed. Oh well 6 years old and the first problem. Can't even call it a problem the liner is a consumable.

On a safety note. my friends and I were a little concerned about welding right next to the gas tank. I believed from research that there was an access hole from the tank bay or that the blind nut was actually in the tank bay. It's not, it's about 1/2" from the wall of the tank bay so there's two separate air spaces and a steel wall between welding and the tank. I know I have no leaks as all rubber lines have been replaced by me. If any doubts about gas leaks no welding.

Bill

[Amskeptic]

it's about 1/2" from the wall of the tank bay so there's two separate air spaces and a steel wall between welding and the tank.

Can you just start a nut on the end of the bolt up there?
Colin

[vdubyah73]

Tied it not enough room to get the tip of my welder in there, the nut is in a u channel. Picture this only vertical with the nut on the bottom l_l there is not really enough room to get the tip in and not really enough room to cut away and rebuild the sides of the l_l either. I think it's another part that the Bus was built around similar to the Y pipe for heat. I'm not taking the engine and tank out just for this repair when i can simply go up to a 1/2" - 20 grade 8 bolt by drilling, tapping and reaming out the shock to make it work. I'll just add this info to my notes for the next owner if I ever sell her. Doubt I'll ever sell her as she is going thru a complete but slow mechanical overhaul. Only to become a parts Bus when I get a rust free but worn out desert bus in my forthcoming early retirement years!

Bill

[vdubyah73]

Ok, the shock mount is all welded up and the shock is back in. Used 3/16 steel to refab the outer layer of the mount. the upper bolt is now a 1/2" 20 instead of the 12mm 1.25 pitch. I just couldn't save it or refab it, just not enough room in there , no matter 1/2'' grade 8 bolt is stronger than a 12mm original. Not really that hard to do with the right tools. My welder wore out the liner for the gun so I had to wait for a new one to come in. would have been fixed last week otherwise.

All the rattling has stopped as well, Believe it was the shift coupler as the stick would be dancing around whenever the rattle occured. I think that things were just to unrestrained with out the shock damping the spring actions.

Bill

[Amskeptic]

All the rattling has stopped as well, Believe it was the shift coupler as the stick would be dancing around whenever the rattle occured. I think that things were just to unrestrained with out the shock damping the spring actions.

Was the frequency of the rattle a road-speed frequency or an engine/driveline frequency? This will help us troubleshoot.
In my experience, road frequency vibrations like poorly damped out-of-balance wheels would rarely involve shift rod rattles. My shift rod rattles when the carbs are out of synch, I get rattles in each gear between 2,500-3,000 rpm.
Colin

[vdubyah73]

The rattle was like when driving over a washboard, except I was driving over washbaord type bumps. . The shifter would be dancing around in synch with the rattle. I don't know if it was the shift coupler, just an educated guess. Absolutley no rattles now. Find me another 30 year old car without rattles, and I'll see if I can buy it!

Bill