Discussion in 'Intermediate CJ-5/6/7/8' started by Jeff Bromberger, Jul 5, 2019.
And here's the cutaway of the valve at rest. Straight outta the DJ-5C manual:
Yeah, it's just a junction block. Serves as a distribution block for the brake tubing and a location for the stoplight switches. If there is a pressure imbalance between the front and rear brakes, it sets off the warning light.
I found a posting referenced in the older AMC forums about how to rebuild it, but the switches on the end seem like maybe they changed things along the way.
If this jeep had the brake light switch on the pedal, that would be one thing. Seeing it on this valve body, well, that's totally another...
Actually, this quite a bit more than "just a junction block". It's a pressure differential switch with parallel brake light switches. Its function is to alert the driver to a brake system failure. In the event of a front or rear brake system failure, the switch detects the failure and completes brake system warning lamp circuit.
What a fun weekend! Well, sorta.
New springs for the front came in. All was going well, but the bushings in the shackles were another story. Now, I am a newbie when it comes to this, and I didn't know that a proper bushing is a tube in a tube with a rubber stuffer thingie in between. I fought the good fight and managed to get the inner tube and the rubber out of the shackle sleeve. The inner tube had rotted/rusted to the bolts, so most of the effort was pulling the decayed rubber out. But I didn't know about the outer tube. No amount of work was getting that one to budge. It is frozen/rotted/welded/whatever to the frame of the Jeep. My solution, partially implemented, was to cut open the new bushings, and then push the new rubber/inner tube into the existing outer tube that's stuck in the Jeep using a lot of dishwashing soap and a huge C clamp. Otherwise, with a new set of Grade 5 bolts, the springs are in place. Axle is still waiting for love and affection from the Hot Rod guys.
Using Tim's advise, I started looking at the bundle of wires kicking around now that there is (technically) no front end on the jeep. I found the Alternator wiring, and how the old Motorola unit used a regulator that's attached to the firewall. That'll be trashed when we get the Delco installed. It is amazing just how simple the whole shebang is - the hardest part are the lights!
So, as I am tracing wires around, I have two items that come to mind. First is this orange wire that was cut (mentioned waaay back in this thread) with a splice going in through a grommet to the back of the dashboard. Second is that happy looking (!) fuse box. I'm debating if I should just go ahead and buy a new wiring harness/fuse box and put it in place instead of the wires I have. My only concern there involves the color schemes and the plug for the ignition switch. All of these generic harnesses seem to have the "GM" wiring colors, but that'll mess up my TSM schematics. Does a sensible harness exist out there that uses Jeep colors? And then, what about that odd shaped plug that is the interface to the ignition switch. Is that part of a wiring harness, or do I have to salvage that out of the existing wires?
And onto that spliced wire... I'm digging under the instrument cluster to get the Sparton turn signal switch out - it is so stiff that it won't move and the rubber wheel needs to be cleaned/reconditioned like a cassette deck pinch roller. So while I an finding the plug at the base of the steering wheel, I look up and see those wires from the splice! Miracle! Trace them back, and they end up in ?the ashtray? The damn thing is rusted shut, so I douse the sides with Liquid Wrench. Finally, manage to get the tray to open and disengage, and there, in amazing glory, is a Radio Shack SPDT toggle switch. It makes sense now...
The old key cylinder was activated by a screwdriver - no key. So the PO must have put in a secret ignition kill switch and hidden it in the ashtray. Pop the switch and there's suddenly no primary power to the ignition coil, and Jeep magically won't start.
If I choose to put that added function back, it won't be hidden in the ashtray this time.
FWIW: I just ordered the Brake Warning rebuild kit from Muscle Car Research, and the two Stop Light switches from Amazon. I still need to get replacement contacts for my wiring harness, but I can probably wing that if I have to.
I just had my FrankenGarand moment. Pardon me while I spin a tale...
In WW2 (and Korea), the primary battle rifle was the M1 Garand. While there was one design spec, it was manufactured by four major contractors (Springfield, Winchester, Int'l Harvester and Harrington+Richardson) due to demand. There were other sub-contractors, too, for things like barrels and sight groups, but that's secondary. There were also minor design changes, too, for durability or reliability enhancements. Didn't really matter - the main point is that it all fit together, no matter where it came from.
When the rifles were returned to arsenals for rebuilding, they stripped them down to the parts, threw them in dunk tanks for cleaning, and then into huge bins for storage. And when a rifle was called out, it was assembled from parts in these bins, ones that had been cleaned and measured to make sure that they still met spec. The rifle was re-issued to somebody new, and the circle went on unbroken.
Then, long after the wars were over, civilians started collecting these relics (the legally proper term for a firearm over 50 years old). Because the greatest proportion of rifles available had mix-n-match parts, we affectionately called them Franken-Garands. Made from parts dug up from who knew where. But, in competent hands, it was able to live again.
Some genius with too much time on his hands made a game of it. He said, "what happens if I put a rifle together where all of the parts are both manufacturer and drawing/rev level correct for a particular date?" Civilian collectors, longing for something reputedly "authentic" spent (and still spend) inordinate amounts of cash for something that probably never existed except on a drawing board. If you have one "Correct Grade" Garand from one manufacturer/date period, why not get ones from each of the four, and then covering each of the minor variants? Needless to say, money changes hands like water...
But to our fighting men, these "correct" rifles are the Frankenstein creations - the abnormal ones in the ecosystem. The battle rifle is a government tool, designed for a purpose, and it served with distinction and honor. It didn't matter who originally manufactured the pieces, because they all cross-fit and, as long as you got a unit which could handle a 10 shot group at 400+ yards, you were happy. The people in the trenches didn't care about variants - they cared about the German/Japanese/Italian guy across the field pointing something back at them.
Now, here I am in the present. Trying to get a stupid unicorn part for my postal jeep. My lowly DJ-5C. Which, when you look at it objectively, is a government tool, designed for a purpose. It served quite a few mail carriers for over a decade of active service, and I'd be afraid to ask how many millions of miles the US-wide fleet racked up. If I was the USPS depot master and I needed to get this busted jeep back on the road because a carrier needed it, what would I do? Keep on looking for a miracle that may never come? Or do something sensible?
It was time to be sensible. I just bought a 1975 Jeep DJ-5D front axle (pictures to follow). It does away with the kingpins and the crazy tie rod end. This means no more waiting for a Hot Rod shop to help design a piece or press out the frozen pins. It's much more robust. It weighs about 2 times as much as the original Clark square axle. It uses standard ball joints and tie rod ends. Plus, as an added bonus, it takes me from 10 inch front brakes to the more current 11 inch ones. Yeah, they're still drums, but that's OK with me.
Was I hesitant? I have invested $$ in the old axle - parts that I purchased in the summer that are too long mine to return. But how much longer can I sit on my butt, praying that my miracle tie rod end drops on me from out of the heavens? Or that Santa will come down the chimney and get my steering knuckles back into shape? At this point I have to say, unabashedly, major thanks go to John Rose, the Postal Jeep maven here in Texas. He made the axle swap come true for not much money. He's an amazing resource when it comes to dealing with the oddnesses of the USPS designs. Ask me about the two different carburetor bottoms (both with the same Carter part number!) that came about due to the change from the BW transmission to the TorqueFlite. He has defused several large landmines before I stepped on them, and (like now) has come to my rescue once I did trigger the device.
In the cosmic sense of things, I guess it goes along with my replacement 1975 engine/trans combination - also from a 1975 DJ-5D. Time to do what it takes to get this thing on the road - I ain't getting any younger. Tomorrow is a new day, and I have a new axle to get mounted. As for the time I invested in the old tie rod ends and bearings, I now chalk that up to learning curve, and this one should come together much faster and with less grief.
I love my CMP FrankenGarand. I’m sure you’ll enjoy your Jeep just as much or more. Better to be on the road than sitting around waiting on parts. I’ve been enjoying your build thread. Please keep it up!
Ladies and Gentlemen! Children of all ages! I now present to you (and please hold all applause until the end):
Yup, the New-To-Me front axle is in place. It's mounted on new springs. It has new U Bolts to hold it all together. It even has that cockamamie spacer under the left side of the axle to try and offset the lean that all Jeeps tend to have.
Here's a close-up of the LEFT (passenger) side of the system:
You can see clearly that the way the engineers went on to remove that funky tie rod end was to change the whole steering knuckle. Not only did they extend it with two ball joint attachment points instead of one, they scrapped the whole kingpin assembly and now I have some beefy-as-a-burrito standard upper and lower ball joints. Oh, you can see the reddish block under the axle (between the gold U Bolts) which is the axle spacer. When I get to the next phase and do the brakes, the old/severed hose will be removed and the new hose will connect to the hard brake line that is visible just "above" the U bolts.
The right side is close but slightly different:
Here, they also have the same second attachment point for the drag link, but it isn't used. This engineering change makes it easier for them to make a Left Hand Drive DJ-5, such as was used in the military. No change of anything - just mount the steering box on the left and put the drag link from there to the right knuckle instead. This is a real improvement in the functional design of the steering system. Amazing what an additional year of development will do for you.
So, as a happy side effect of this, I am moving up to 11 inch front brakes. You have to remove the three bolts and pop open the hub access cap to get the brake drum to pop out:
I have to measure that humongous nut on the end of the axle to get the bearings out. They click as if they are ball bearings and not cone/roller bearings. The grease is all water contaminated, so it has to come out no matter what. Anybody have a good pointer on what they call the gasket between the hub and the end plate/cap? It is sorta round, but has six bolt holes through it. I'm sure they are common, but every time I search for front wheel gasket I either get seals for locking hubs or for a differential. As you could plainly see, this ain't one of those.
Back in business, as they say. Tomorrow is Torque Day, as the U Bolts (and the spring bolts, too) get what's coming to them, as per the TSM. Then I have to get the bearings done before I attack the brakes. I'll probably also wield the mighty Pickle Fork of Tie Rod Justice so that I can get those old ends separated and replaced.
Who knows - maybe I'm feeling confident enough to purchase a set of REAR springs and replace those, too!
Minor project for this week is to write up a To Do List/Poster and hang it so that I can track my progress.
That axle looks way safer. The nut and gaskets are the same as the cj front axle and actually looks the same as the early bantam trailers.
OK - change of plans for today. The axle can sit a few more hours while I get to do a quick evaluation of the replacement motor:
So, the engine is dated April 29th, 1975. It's close enough to my Jeep's date of creation, so I have little to complain about. Or so I think.
Nobody tells you how annoying it is to pull the engine off of the transmission. There's the starter, the transmission dipstick tube support, the two small bolts holding on the lower access plate, two more bolts holding on the upper access plate, and then the FOUR MAIN BOLTS. And you're doing all of this unbolting with the unit hanging from a hoist. Fun you could never imagine. But, when you finally separate the engine from the 727, there's a hidden surprise in there! Hello, Mr. Torque Converter!
You can't mount an engine to a stand if the flywheel is attached, and you can't remove that until you get the converter out of the way. How do you get the damn thing off of the flywheel? The four bolts barely are accessible from any position except the bottom, and with the engine swinging freely from a hoist, there is pretty close to zero chance that I want to crank the main shaft around. Putting it back together will be a puzzle and a half. Next, the flexplate/flywheel has to come off. There's six chintzy Class-8 bolts holding it on. Well, maybe only 5 are Class 8, they have deeply scored bolt heads. It is as if you could be crazy and try a screwdriver to get them out. The 6th? Nothing on the bolt head whatsoever.
I broke out the air wrench, and with about 3 minutes of attention each, they surrendered. The flywheel is mine! Or maybe I should say "Urgh, the flywheel is mine..."
The flywheel is probably better called a flexplate here, as there is zero mass to the dang thing. And, oy, there's a chunk of the gear with missing teeth, as you can see. Should it surprise me that this section was positioned right at the starter?
I suspect that this type of damage is a non-repairable, so I'll have to get a new (or New To Me) one somewhere. It also makes me think the starter gear is hosed as well. I'll have to examine it closely.
Any ideas why this would be so chewed up? I have a sinking feeling (rhymes with the word sneezed) when I see destruction like this. Now that I am firmly bolted onto the engine stand, I'll try to see if I can bar over the main shaft:
I might pull off that auxiliary pulley first, though.
On any engine there are specific places that the engine tends to stop, between compression strokes. I'd think there would be 3 such places on this flexplate, separated by 120 degrees.
Likely a bad starter or the wrong starter. I don't think you need to worry about the engine yet. Flexplate is not expensive.
More Information for ATP Z102
A727 is the 727 with an AMC case. This is what RockAuto gives for the Cherokee with a 258 and the A727. It's surprising to me that they spec the same flexplate for the V8 and the 6, since the balance is not the same. You'd need to compare the new and old part. Worst that could happen is you'd have to have your local automotive machine shop balance the new flex plate like the old one.
Maybe the engine seller will send you a good flex plate. It seems cheesy, but since this should be a neutral balance flexplate, you could redrill it and rotate it 60 degrees.
You may want this one More Information for ATP Z101 even though it's spec'd for the smaller transmission. Cheaper too.
I'm reading lots of reviews across different sites about how these plates are set up for V8 engines and not the 232/258. Learning time here: if the device is circular, and it is balanced around the center (through the axis of rotation), then why does it matter what engine it is bolted up to? Yeah, the holes have to line up, but radially balanced is radially balanced, right?
Not from what I read, but I can't fathom why...
Due to their packaging, inline 6's tend to be internally balanced inside the engine. However, a lot of compact V8's don't have enough room inside the block for large enough counterweights to fully balance the engine internally (without resorting to expensive exotic metals). For those engines, the final balancing of the engine rotating assembly needs additional weights on the flywheel/flexplate and front damper pulley.
Here's some Ford V8 parts where you can really see how the damper and flexplate are NOT radially balanced in and of themselves. The damper has a large cast-in weight and the flexplate has a weight welded to it.
Of course, they need to be indexed to the crankshaft properly to balance out the engine. The damper uses the keyway. The flexplate holes look equally spaced, but one hole is offset, so it will only bolt on one way.
If you put one of these items on your internally balanced inline 6, you've got a nice paint shaker.
There are two balancing schemes. First is internal or "neutral" balance. In this case, the motor does not rely on the flywheel/flexplate and harmonic balancer (on the front of the engine) to balance the rotating assembly - crank, pistons, rods. There is also external or "Detroit" balance, where the flywheel/flexplate and harmonic balancer are balanced with the rest of the rotating assembly.
The 232/258 is neutral balanced. I understand this is usual for inline six engines. The AMC V8s are externally balanced, and the flywheels in particular are specific to the displacement of the engine. 304, 360, 401 flywheels all different, and sport an eccentric balance weight - it's a big knob on the flywheels, and a welded-on weight on the flex plates. It is possible that the torque convertor has weights on it. The 1980 parts manual only shows one flexplate for the 727, and I thought the Cherokee and Wagoneer with the 258 and towing package got the 727. Maybe not by 1980? If no 258, the only other 1980 Jeep with the A727 has a 360.
The 232/A727 never appeared in civilian vehicles as far as I know. The balance of the 232 and 258 is the same, and they share flywheels. Looks like the A909/A999 flexplate is the same diameter and tooth count as the A727 flexplate, and the listings might assume that the only app for a A727 is a V8.
Quick change of topics: I promise that I'll get back to engine balancing and flexplates!
Say, didn't we all learn the primary lesson from the movie "Ghostbusters"? I'll give you a hint - it isn't "don't involved with possessed people." Repeat it with me now:
DON'T CROSS THE STREAMS!
Well, I have firsthand experience of what happens when you do:
This is the inside of that brake proportioning valve. Not the glove, mind you
I learned from the manuals that the USPS always used DOT5 brake fluid in their vehicles. It is supposed to be painted on the inside of the hood and on the firewall near the master cylinder. High performance fluid due to the hundreds of stops a day. The brakes cook more often then they wear out. And there's warnings everywhere on the net about mixing brake fluids. Here's your proof. Whatever wasn't brown and gelatinized was dry and scaly:
Those are the two plungers from inside the switch. I had to use a piece of drill rod to pound them out - no way that this valve was doing anything useful the state it was in. If it matters, it was pegged to one side, so the brake warning light would have been on for the last driver. There's a tiny O-ring at the base of the rightmost side of the plunger. Hard to tell where anything is on the lower image.
Even now, with over an hour of soaking, brushing and cleaning, they still aren't picture perfect. At least they slide through the bore of the brass valve body without problems. I have new O-rings, springs and copper crush washers to replace everything that could wear out.
This brown sludge was all over the inside of the master cylinder, too. I'm now 95% certain that I need to go and buy new brake line material, because I suspect that this luscious state of affairs is now everywhere in the system, and a simple "blow the lines clean" won't remove this slime. Tack on another day of work to make up for a cheapskate previous owner.
Now, back to the previous discussion, already in progress!
PS: Front axle and springs are all torqued in place now. Tie rod castle nuts are off and waiting to have the ends separated and replaced. And new rear springs are due on Friday. Maybe I can get the brake lines in this weekend as well, so I can go on vacation with a warm positive feeling.
Jeff, your account of working on this Jeep should be in a book. You are a VERY talented writer. I love your sense of humor in the face of impending doom.
Keep up the work, and if you ever visit N California I'd like to buy you a beer.
Back to flexplates and balance...
I think I understand what they're trying to get at, and now possibly understand why there's that "dampener" at the front of the crankshaft, too.
So, why then are flexplates so darn thin? Wouldn't you want a large mass to be spinning in order to conserve momentum? Especially if the engine is internally balanced, so you're not slinging an asymmetrical gizmo around? You want as much balanced in the engine as possible, using external compensation only as a last resort... And since most of the vibrations and such are handled in the block of an inline 6, wouldn't there be an advantage in maintaining RPMs with a heavier load (of course, there's a cost in startup involved)?
I just sent an email off to B&M to ask if the 727 and the 904 can use the same flex plate. I don't have the diameter of the screw holes for each torque converter. According to "Iffy-Pedia", both of these used the same 10.75 inch diameter torque converter, but there is no promise that the mounting holes are in the same place.
Oh, and I must say that I learned something else. Way back in this thread (#91), I mentioned that of the six bolts that held on the flex plate, five were deeply marked as Grade 8, and one was not. What I should have said was that I found the index bolt... Those six holes in the flexplate are not all equidistant. One is deliberately drilled off kilter, just so that there's a permanent index hole. And it's this one odd bolt that is placed in the one odd bolt hole. It was an encoded message that flew over my head at the time. I am older and (barely) wiser about such things now.
One thing to remember is the auto will have the mass of the torque converter for enough inertia for a smooth idle the flexplate just holds it and the ring gear in position. An automatic won't benefit much from any extra mass on the crank because you're not lugging around in 2nd without a synchronized 1st to shift to. Unlike an I6 An oddfire 90deg v6 (ie buick225) needs lots of mass because it is uneven in its cylinder firing pattern and the mass helps it level out harshness (think Harley motorcycle at idle). Race engines that don't need to run smooth but must accelerate and produce as much power as possible will have the cranks drilled to be lighter and have very light flywheels when coupled to a manual transmission.
As Jw60 writes, you include the mass of the convertor when considering an automatic. You need the flex plate to support the starter ring gear, and it's a convenient place to attach balance weights for external balance.
Realize that momentum cuts both ways. Too much mass and it takes more power to spin up and spin down the mass. This has a negative effect on fuel economy. More mass also slows down how quickly the engine can change speed - sometimes that's what you want, but not always. Sporty cars tend to run a light flywheel both for power and "responsiveness." So the size of the rotating mass is a compromise between competing effects.
In modern times, fuel economy has become a much more important factor, so the trend is to go lighter. In 1981, Jeep lightened everything they could in the 258; crank, block, manifolds, valve cover. Your 232 already has a heavy crankshaft with 12 counterweights, while the newer 258 has only 4. The 232 did not survive long enough in production to be lightened. The 4.0L is also built in this new, lighter configuration.
Pretty sure that A904/A999 flexplate will work for you. Aftermarket listings don't consider the oddball applications like your DJ. Are you friendly with a local parts store? Usually they will help you if you ask - costs them nothing but their time to order-in either of those parts. Take your flexplate to the counter and chat with them about what you are doing. When they aren't busy, they'd rather be talking with customers than dusting the stock or sweeping the floors or whatever.
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