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Discussion Starter · #1,281 · (Edited)
OK been working on some stuff on the DeScrambler. My most recent project has been installing Air Bags on the Rear Suspension.

The reason for needing them was two fold.
First; I needed to be able to adjust the ride height of the Jeep when loaded.
Second; I wanted to take some of the top heavy/roll out of it. It was kind of floppy when going around corners or off camber turns.

Well after my Test Drive this afternoon I have succeeded on both. With 20 psi in each Airbag, (plumbed independent of each other) it goes around corners very smoothly now, and the rear end is up just about an inch to bring the Jeep level.
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Kind of self explanatory how they are assembled. The top bracket is bolted to the frame rail and the lower is bolted to the rear of the top plate of the Spring Perch.

Important thing here is that they work, and the difference in the ride was noticeable within the first 1/4 mile!

Next Project is the Ring addition to the Vibration Damper.

Randy
 

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Discussion Starter · #1,282 ·
OK Everything was hunky dory except for one small problem. The airbags I chose ( I had one already from the Traction Bar Project a few years ago.) were nearly fully extended when installed so if the axle tried to Droop (Important part of Articulation) the Air Bag would act as a limiting strap and prevent the axle for dropping down on the high side.

This would severely limit the off-road capabilities of the Jeep.

The solution was to order the longer Airbags and Retro Fit them in place. Everything was nearly the same except I had to open up some holes in the brackets to accommodate some minor differences.

The old bags had a max extended length of 7.1" and they were already at 6 7/8" installed. They had a compressed height of 2.2 " but the Bump Stops on the axle would have never allowed that to happen. Basically 5" of usable travel but it was all used up.

These new bags have a extended length of 10.5 " and compressed height of 4", so there is 6.5" of usable travel. And they are at 6 7/8" installed and pressurized to 30 psi which lifts the Jeep level. So in the end there is 4" of droop available which should be enough to make it to the end of the shocks travel which will ultimately limit the downward travel of the axle anyway.

Here's a Pic of the new Airbag installed. Sure are plump little suckers.
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Note; These little airbags can max out at 1100 lbs of lift each when pumped up to 100 psi at the beginning of the stroke. . That's kind of alot but they will do 750 lbs each at 100 psi at full extension. Point being they will do anything needed for this application. .

Still looking to plumb these into the interior of the car, just haven't figured out the ideal place for them yet. I want a Manifold with a Gage for each side.

The other side is a Mirror Image, so use your imagination.

Randy
 

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These are all "Isspro Gauges" and the 3 primary ones OP, WT, and EGT all have 'Amplifiers' which may be the problem.

OP, no problem, WT just quits then starts back up when power is interrupted.(turn key off, and back on.) Reads accurately when on.

EGT is useless. all over the place sometimes at 600 then 300 then zero all over the place with no rhyme or reason.
I have to get with the Isspro Engineer to help fix it. I think it's a bad probe or maybe the amplifier? Just one more thing to weed out.

Working on finishing the doors right now and will get back to the Gauges a little later.

I tweaked on the doors and windows yesterday and got them to fit the holes pretty close. Now they open and close and latch right. That made a huge difference and Weatherstripping will finish that off nicely.

The weather stripping will be "Unique!"

I took the Steering Wheel apart today and tightened the Screw holding the turn signal lever up, also found I had not fully tightened the actual Steering Wheel Hub??? oops ,,,, That is fixed and everything is fine in there now.

Probably gonna do Dynamat on the Cargo Area Floor, it would be quick and easy to do and cut down on the noise some more. I also really need to find /make a different Pulley to run the A/C So I can use the Big Fluidampr, Vibro Damper I have, as there are some regimes of engine speed that still vibrate more than others. The entire body is fiberglass and it does buzz around at low idle and about 21-2200 RPM's . Not horrible but something that can benefit from some fine tuning.

Plenty more to do.

Randy
who did you end up using for weather stripping? I too am running a Fiberglass body and went with fairchild and had issues with the half-doors not sealing to the tub properly.
 

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Discussion Starter · #1,284 ·
I haven't done anything with the weather stripping yet. I haven't come up with a workable solution and Nobody want to touch it so I am stuck until I figure out a way to deal with it.

I am currently working finish plumbing my Airbag System which is working well. Next project is the Ring for the Vibro Damper to increase it's weight and take some more shake out of the engine.

I have been driving the car on the Street and Freeways alot more now. The car has 4500+ miles on it now.
Last tank of fuel I got 19.0 MPG out of it which is the best so far. It is running at 2100 rpms at 65 mph and 2200 at 70 mph which is fine.

Noise inside the cab is still a problem and I drove it about 90 miles today, and it does wear you down somewhat. But part of the noise is coming thru the doors and not enough Weather Striping and Body Vibration generated by the engine and transmitted thru the body mounts and engine mounts.
I'm sure the ring on the Vibro Damper will cut that down alot but the Weather Stripping is the main thing that needs to happen as it will seal up the doors and prevent them from rattling and stop the wind noise coming in...

Randy
 

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Can you post up brand/model/part numbers for those air-bags Randy? Gotta be helpful for everyone else.

How do they look fully compressed? Often with those the bags roll down over the lower mount so you need a round extension to mount them on if they don't have it as part of the lower mount.
 

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Discussion Starter · #1,286 ·
They are Goodyear Airbags I got from McMaster Carr. They are the ones that have a 10.9" fully extended length and will support 1100 lbs at 100 psi. The grid in the catalog shows the Mc Carr part number. 9538 K-26

The Goodyear part number is on the bottom of the bag so I can't really get at it without taking them apart.

When they are deflated they do collapse around the bottom standoff in the bag. However they can't go below the bottom mount because of the bump stops, if they could go shorter then the top folds over itself like in the pics above which show them deflated as they came from the factory.. I had to buy a small manual vacuum pump at HF to suck them down more so I could get them into the mounts when I changed them out.

Randy
 

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Discussion Starter · #1,288 ·
After driving the Jeep for a few hundred miles with the new Airbags installed I have to say the addition was a success. The Jeep doesn't roll around nearly as much as it used to and is much more stable on the winding mountain road going to and from my Shooting Range.

I just increased the Air Pressure in my tires yesterday. up to 25 psi now. Seems I have been driving around with the tires inflated to about 12 psi for the last few months.. The sidewalls on the tires are so thick that they weren't bulging very much at all and as a result I hadn't paid much attention to them.

Randy
 

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Discussion Starter · #1,289 ·
OK; 5,000 miles in I finally had my first Mechanical Failure. My Traction Bar Broke !
It broke right at the juncture of the Lower Bar and the Axle Clamp, and the Top bar and the Plate that attaches to the top of the Diff (See arrows)
And it broke clean in strait lines across the tubes.
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I was coming home from Skeet Shooting Thursday morning and I heard this small snap when I hit the sharp bump on the road which I try to avoid. I didn't think anything about it as I have hit that same bump 50 times in the last few months. Everything was Hunky Dory coming down the mountain and I went to McDonalds to get Lunch. As I walked out I noticed something hanging from the under carriage of the car. WTF is that? After closer inspection I found the Traction Bar hanging from its upper mount ! It had separated from the Axle Mounts in two places, and I never thought in a million years that thing would ever fail. But It DID! I'm just glad it happened close to home as if it would have happened on a trail it probably would have taken out the Rear Drive Shaft when the Axle Rotated Hard during hard acceleration. Exactly what the device is supposed to prevent.

And now I've got to fix it and obviously beef up the connections to the Axle Mounts. I also have to replace the Plastic Inserts in the Jonny Joint on the other end as they are beat up pretty good. That has needed to be done for some time as the snap ring that holds the joint together had popped out of its groove early on. Wasn't going anywhere so I just left it loose.

The biggest problem is to get everything to line up again as the Bars and the Jonny Joint were initially all tacked in place with the bar in place on the jeep. Then welded out on the table. I can't do that this time as the body is in place and I can't get at it to tack it. It will be a project to get everything to line up again, but I'll figure something out..

I have no idea why this happened and will probably have to hang a GoPro underneath to see what is happening in real time as I drive. But the breaks were clean and in the Heat Affected areas so it broke in the weakest places. I can make them "NOT the Weakest Places" during the rebuild.
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The Frame Mount for the front end of the bar was unscathed. So I am blaming the heat affected areas as the culprit.

Randy
 

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Discussion Starter · #1,290 ·
So My Jonny Joint Rebuild kit came in and I remembered why the snap ring popped out prematurely. It was never in the groove all the way because I couldn't compress the plastic inner parts enough to get to the snap ring groove.! Close but not right.
I went on line and they sell "Jonny Joint Assembly Tools" for $100 !. I need to do One, so that was out of the question..
I went to my favorite Hardware store and found everything I needed to make it happen and my girlfriend, who owns the place, just gave me the bolt, nut and a few washers. Had to cut the coupling nut in half and face the ends and make a relief cut so the snap ring could get compressed enough to make the groove. Done!
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It worked great, and I am sure I got the Snap Ring in right this time!

Note the line on the housing? It was there so I could time the two plastic female pieces together as they have lips on the faces that have to go together correctly or you can't compress the inner parts enough to get the snap ring in the groove. This is not just a matter of putting them in the housing and rotating them until they mesh. They have to be compressed to even get them in the housing so you can't rotate them once inside. They have to be lined up as they are started in the housing. Hence the lines on the housing and on the plastic parts as well. Also the Ball Shaped Center piece has to be in there as well because it is what gives you the rotation like a Spherical Rod End. This thing is just a big one of those that you can take apart and rebuild. They are used mainly on Suspension Links on Long Travel Suspensions for vehicles like Rock Buggies and the like where the axles are rotating nearly 45 Degrees in both directions, but are solidly located side to side so the only way they can move is to rotate around the drive shaft. They are pretty spectacular.in action and can climb things that defy comprehension.. Having 600 HP available doesn't hurt either!

Randy.
 

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Discussion Starter · #1,291 ·
Here's pics of the broken pieces that I removed from the axle today. This was not easy as I was upside down lying on a Creeper trying to break 1/2" bolts loose that were tightened 10+ years ago. I finally got all of them loose and got filthy in the process. Getting everything lined up so it will bolt back together will be challenging!
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I also have to beef all the joints up so they don't come apart again.

Randy
 

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Randy, that's a Cummins telling you "I'll show you where your weak points are". That low end torque just loves to break things. Over the years guys have had bent frames, twisted drive shafts, broken ring gears, and now we can add a traction bar to the list.
 

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Discussion Starter · #1,293 ·
Yeah I get the torque part. Every time I pull away from a light or stop It lifts the left side of the car as the axle Rotates. The Traction Bar is controlling axle wind up, and it took probably close to a thousand cycles to finally break it. but you can see where the weak points were. When I get done with it, those won't exist and we'll be looking for the next Weakest Point on the car.

I'm feeling the work from yesterday. Breaking loose 6, 1/2" bolts upside down under the car I was in positions I hadn't experienced in a while.

I'm feewing it today..

Randy
 

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It's hard to see exactly what's going on with your traction bar, but I think it's flexing diagonally in a flat plane and that's why it broke.

Is there room to make it more like a vertical truss and give it some flexy joints onto the axle mount so it can wobble sideways a bit without bending the steelwork?
 

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Discussion Starter · #1,295 ·
In this picture you can see the entire Bar. What is missing is the Forward Mount which attaches to the holes in the cross member shown. There is a fixture that hangs directly over the Jonny Joint and has a tube with Spring Bushings and a Shackle which receives the Jonny Joint (Large Heim Joint.) at the bottom This allows some fore and aft movement and allows the axle to flex around the drive shaft. as well as rotating up and down as the springs flex . The Eye of the Joint is in the same line as the Forward Spring Eyes.so as the axle moves up and down the Bar rotates with it.
There aren't any significant side loads, but what does happen is that under acceleration the axle tries to rotate and pushes the bar upwards which in turn lifts the left side of the Jeep up.

Pretty sure the repeated action of the bar pushing the frame and body up is what eventually fatigued the welds and broke the bar. This happens to some degree with every start to move forward in normal driving. Pretty sure the lower bar broke first as it was essentially a butt weld on to the front face of the Axle Clamp. Then the top bar followed shortly there after.

My biggest problem will be getting everything to line up when welding it back together.

Randy


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Yeah that's it. You'll need to either triangulate that down to the bottom of the diff-head to stop it flexing across it's flat plane or make it more vertical (more 2 dimensional) and give it some rubber bushings onto the axle to let it self align.
 

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Discussion Starter · #1,297 · (Edited)
So I glued it aback together yesterday but need to do the reinforcing after I test fit it. It looks like it went back together fairly close to original and if it goes back on the Jeep without having to beat it into submission I will just reinforce it with Fish Plates over all the broken areas. and be done with it. Pretty sure it gave up on the top plate first as that was the weakest place, then worked the bottom bar until it broke which was probably not to long after..

I'm still formulating a plan for how the Fish Plates will look but I understand Fish Plates pretty well from my Fabrication days so they should work just fine for this application.

There isn't really any way to make that bar be 2 dimensional. as the only place to get ahold of the diff is on the top of it where is has attachment points for Suspension Bars. This is a Special Dana 60 Center Section made by Currie Enterprises called a Rock Jock built specifically for Custom uses like Rock Buggies with 4 link suspensions and the like. Ordinarily there would be a Vee Bar anchored to the mounting holes on the top of the Diff that prevent side to side motion and then two lower bars that prevent rotation of the axle around the Drive Axles. IE preventing Axle Wind Up.

Randy
 

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Discussion Starter · #1,298 ·
OK,,, It is back together and working again.. I managed to get the Jeep on a Rack so the axle was dropped as far as it could go so I had plenty of room to chase the holes in the top of the diff. That only took a few minutes, then I got help reinstalling the bar onto the Axle. all the holes lined up just perfect and then I reefed everything down on the axle.

The hole in the Jonny Joint on the front end was about 2" below the shackle and we used some Screw Jacks to bring it up on the left side so that the hole aligned enough to get the bolt back in. This all took about 45 minutes to execute.

Now we'll see how long it lasts. If it breaks again soon I will have to redesign the whole mess with a Vee Barr running from the frame rail to the center of the diff.

But I'm back up and drivable now and can go on to other things I was working on before the catastrophe!

Randy
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Discussion Starter · #1,299 · (Edited)
OK now that the Traction Bar is fixed I am onto another small project. Shore Power.

There is a Small Parasitic Power Loss in the electrical system. I have been looking for months for it and have come up with nothing concrete. Yesterday while under the hood I heard a faint buzzing noise that sounded like a small motor running. I couldn't find it and there isn't anything that should be producing that type of noise, but after disconnecting the batteries it stopped so I know that is what is draining the batteries. It takes about 2-3 weeks of not running the engine to kill both the Optima Batteries below 11V.

My solution to this is to add a Shore Power Socket and a Dedicated Battery Charger to the Jeep. It needs this anyway to be able to run my Refrigerator or any other 110V accessory.

I have to bore a 2" hole thru the side of the body to mount the receptacle.. Just have to get in the back of the cargo area to see exactly where I want it to sit and where the Battery Charger will go.

Randy
 

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Discussion Starter · #1,300 ·
News Flash: I found it!

It is the Heater Mixing Valve making the noise? sounds like a small Electric Motor. Finally got my hand down to where I could get ahold of it and heard a difference in the noise.

Why this thing is buzzing is beyond me,,, but it is .

Randy
 
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