Nashville TJ's Build - Continued
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You may recall that back in Moab I did this:
That truss was one of the very few pieces on the rig that I have not fabbed myself. The failure was caused by this horrible, non-penetrating weld from Dynatrac:
So I did this in the driveway.
The repair was successful, but at the time the welder was giving me fits because the Jeep would not hold 2000 rpm to run the welder - it just kept running away and creeping up to wide open. So, my friend Thomas had to sit in the Jeep trying to keep the idle in range with the pedal. Up and down, up and down. It did not work well.
I figured out later that this had happened and was causing the bad idle. 250+ degree IAT's wreak havoc.
It did get a good bit better later in the day after the Jeep sat in the garage and cooled for a while, but was acting up the entire time we were working on the truss. It was running a bit better later that evening when I welded Ben's shock mount - but it was still just passable.
Despite the challenge, Thomas and I did get the truss fixed, but the welds - although well penetrated - looked like this:
Definitely not my best work, but we did then wheel Pritchette and Moab Rim without issue, so it was definitely solid.
But, since I had to pull it anyway to paint the thing, I decided to redo it to make sure it is right.
That truss was one of the very few pieces on the rig that I have not fabbed myself. The failure was caused by this horrible, non-penetrating weld from Dynatrac:
So I did this in the driveway.
The repair was successful, but at the time the welder was giving me fits because the Jeep would not hold 2000 rpm to run the welder - it just kept running away and creeping up to wide open. So, my friend Thomas had to sit in the Jeep trying to keep the idle in range with the pedal. Up and down, up and down. It did not work well.
I figured out later that this had happened and was causing the bad idle. 250+ degree IAT's wreak havoc.
It did get a good bit better later in the day after the Jeep sat in the garage and cooled for a while, but was acting up the entire time we were working on the truss. It was running a bit better later that evening when I welded Ben's shock mount - but it was still just passable.
Despite the challenge, Thomas and I did get the truss fixed, but the welds - although well penetrated - looked like this:
Definitely not my best work, but we did then wheel Pritchette and Moab Rim without issue, so it was definitely solid.
But, since I had to pull it anyway to paint the thing, I decided to redo it to make sure it is right.
Over the weekend I took the time to redo the truss. First order of business was to get in there with the angle grinder and the die-grinder and clean up the old, nasty welds.
Once the weld failed at the mount, the next area that failed was on the back side of the bracket on either side of Thomas' left thumb in the pic:
There is plenty of clearance with the diff in that area, so I cut a rib on the band saw to reenforce that part of the truss:
And tacked it in place:
After verifying the fitment, I rewelded everything, and then some:
Once the weld failed at the mount, the next area that failed was on the back side of the bracket on either side of Thomas' left thumb in the pic:
There is plenty of clearance with the diff in that area, so I cut a rib on the band saw to reenforce that part of the truss:
And tacked it in place:
After verifying the fitment, I rewelded everything, and then some:
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I never asked how you got the truss un bent/twisted at you rental? Did you have a vice/BFH?
Next question: How can you recognize a weld with poor penetration like that before it fails? Or can you? @AirborneTexasRanger?
Next question: How can you recognize a weld with poor penetration like that before it fails? Or can you? @AirborneTexasRanger?
A difficulty with throwing the heat at this thing is that it fits very tightly into two milled grooves in the top of the diff. In Moab I was very, very careful about welding the truss as I did not have any good way to straighten it if it moved too much to fit. Thomas and I were both pleasantly surprised when it went right back in after the driveway welding job.
But I knew that throwing the heat of all these fat welds under the truss was definitely going to draw the two mounts toward each other, and then would not fit in the grooves. But unlike in Moab, here in the shop I have a way to deal with this problem.
I measured the width of the mounts before and after welding. It moved about 50 thou. But, it was an easy and expected/planned fix:
Once comfortable that it would in fact fit, finally primer and paint:
And back in the rig it goes!
If this one fails, at least I know whom to blame....
But I knew that throwing the heat of all these fat welds under the truss was definitely going to draw the two mounts toward each other, and then would not fit in the grooves. But unlike in Moab, here in the shop I have a way to deal with this problem.
I measured the width of the mounts before and after welding. It moved about 50 thou. But, it was an easy and expected/planned fix:
Once comfortable that it would in fact fit, finally primer and paint:
And back in the rig it goes!
If this one fails, at least I know whom to blame....
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Big hammers, some wood blocks, a little grinding/cutting, and a bunch of cussing.
No way to tell that weld was bad beforehand. On the surface, it looked fine. That's why you have to know how to do a good weld to start with.
The
You can tell if you're the one welding it & you know what to look for in the puddle.
Also:
Wow. That made my night.
And finally painted...
...and installed.
...and installed.
So, I often find that I am not nearly as smart as I think I am...
Since I run beadlocks, I mount my own tires. The toughest thing about changing a tire on a beadlock is breaking the inner bead - which is tough on a big tire.
A few years ago, I build this contraption to break the beads. It bolts top the floor and works fairly well:
View attachment 541464
But it's still a lot of work - and even with the leverage of that 6' tube it takes a good bit of effort to break the inner bead.
You may recall that I cut a sidewall out in Moab a few weeks ago. I ordered a replacement tire (gotta love Discount's road hazard warranty) which came in this week. Now both Nina and I have been pretty sick after getting back from Mexico (Covid, which has really been kicking my ass), and I've not felt anywhere near up to fooling with the tire. But for the last couple of days, I've been on the upswing.
Now I still did not feel up to getting out the bead breaker and going at it, but I wanted to get back out into the shop and do something.
So on a whim, I did this:
View attachment 541465
And man, was that crazy easy! Much, much easier than the old setup, and no need to haul that heavy thing out, bolt it to the floor, and then wrestle the big tire up and onto it. Say what you want about the high lift....
Anyway, got the new tire installed:
View attachment 541466
This week I'll take it in to get balanced, and call it good.
The tough part is now I have to find a place to carry the Hi-Lift on the rig again....
Pretty timely to see how you broke the bead on your beadlocks. I tried three different methods the first week of July because I’ve got radial runout on two tires and I couldn’t get the bead to break to rotate them on the rim 180*. I may borrow my neighbors hi lift jack.
A few more odds and ends repairs leftover from Moab.
First up, you may remember my GMRS antenna flyswatter repair from day 1 in Moab:
Strangely enough, it worked for the entire trip.
But I did pick up a replacement antenna a few weeks ago, installed it, and today I tuned the SWR (Standing Wave Ratio). You do that by testing it with an SWR meter and trimming the length of the antenna to get the SWR down as close to 1 as possible. 1.2 is pretty good.
It's important because a high SWR from an untuned antenna, say 2, 3, or higher, can kill a transmitter as I understand it.
The SWR varies a bit across the range of channels, so I tuned it on 15 - about in the middle. It started at about 1.5, but after trimming a few times (I trimmed off a total of about 3/8") it got down to between 1.1 and 1.2. Happy with that.
Channel 22 was right at 1.2:
And channel 01 was 1.1.
I'm only marginally familiar with what all that means, but it's tuned.
First up, you may remember my GMRS antenna flyswatter repair from day 1 in Moab:
Strangely enough, it worked for the entire trip.
But I did pick up a replacement antenna a few weeks ago, installed it, and today I tuned the SWR (Standing Wave Ratio). You do that by testing it with an SWR meter and trimming the length of the antenna to get the SWR down as close to 1 as possible. 1.2 is pretty good.
It's important because a high SWR from an untuned antenna, say 2, 3, or higher, can kill a transmitter as I understand it.
The SWR varies a bit across the range of channels, so I tuned it on 15 - about in the middle. It started at about 1.5, but after trimming a few times (I trimmed off a total of about 3/8") it got down to between 1.1 and 1.2. Happy with that.
Channel 22 was right at 1.2:
And channel 01 was 1.1.
I'm only marginally familiar with what all that means, but it's tuned.
Next up, you may also remember that my intake came apart. I'm pretty sure it happened sometime prior to repairing the truss as that's the only way I can explain my difficulty controlling the idle while welding. But, I didn't discover it until the next evening - after wheelin' Pritchette. 
All day during Pritchette, I was having trouble with knocking/detonation. Not horrible, but it was enough that I noticed. I mistakenly chalked it up to a combination of the heat (100+ by late afternoon), and 91 Octane Moab fuel. Fortunately, I led that day so not as much dust - or that could have been very, very, bad. I did check the throttle body, and it was clean, so I dodged a bullet on that one.
Next time that happens, the first thing I will do is OPEN the DAMN HOOD!
Anyway, that's not happening again...
All day during Pritchette, I was having trouble with knocking/detonation. Not horrible, but it was enough that I noticed. I mistakenly chalked it up to a combination of the heat (100+ by late afternoon), and 91 Octane Moab fuel. Fortunately, I led that day so not as much dust - or that could have been very, very, bad. I did check the throttle body, and it was clean, so I dodged a bullet on that one.
Next time that happens, the first thing I will do is OPEN the DAMN HOOD!
Anyway, that's not happening again...
Do any of the hemi's come with knock sensors?
I feel you on low grade 91 in small towns. My jeep isn't happy with the supposed "91" where i live. Its a pain to always need to make a 40 mile round trip for gas just to avoid detonation
I feel you on low grade 91 in small towns. My jeep isn't happy with the supposed "91" where i live. Its a pain to always need to make a 40 mile round trip for gas just to avoid detonation
Dual knock sensors, one on each bank.
It only pings for a sec, and then the ECU pulls timing and it stops. Of course, so does the power….
But it was definitely not the fuel, nor the heat - it was IAT’s through the roof. After I reconnected the intake, it ran fine once again.
Another example of why i should find a windstar intake.even if it isn't apples to apples
Gave the tow pig a little love this morning. It had a good bit of rake - I run Airlift bags in the back, and even on the lowest pressure (5 psi) it lifts the rear just a bit.
So I added Readylift 1 1/2" leveling blocks in the front.
Easy peasy. Only took about an hour. Also had to center the steering wheel just a schooch.
So I added Readylift 1 1/2" leveling blocks in the front.
Easy peasy. Only took about an hour. Also had to center the steering wheel just a schooch.
For those of you who met my neighbor Thomas out in Moab, he is making some progress on building his rig. Not the 4-door JL he had in Moab - this is his 2-door JK. Dynatrac Pro-Rock 44 up front, and a 60 in the rear.
And this is next...
And this is next...
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