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Discussion Starter #1,141 (Edited)
Yes the spacer is in the back and the Alt can't be moved farther forward in it's mount. It's misalignment puzzles me as well. This was probably a Rebuilt Alt from a Parts House and not the exact one for the engine. Thus the wrong Pulley. However after closer examination It appears that it does in fact have the right pulley See Pics.

Also from the pics can you verify that the Alternator is in fact a "Delco 12 si?" My Cummins P30 Manual says it can be anyone of the ones you mentioned but it looks like a Delco to me?.

Still looking like a Spacer behind the pulley will ultimately be the correct fix.

I am going to break the Jeep today to send the Tach back to Isspro and also dealing with the Steering Gear and Alternator. So there will be a lull in my testing/debugging for now. All this stuff has to be fixed and if I can drive it, it won't get fixed as it is more fun to drive it than work on it. DUH?

Randy
 

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Alternatorparts.com has a large selection of pulleys. The owner is an older fellow named Randy. I've purchased from him in the past. He is very knowledgeable. Using his website and tech support, I converted my son's 1995 4.0L Jeep Cherokee from the stock 90 amp alternator (6 rib pulley) to a 136 amp alternator (7 rib pulley) from a 5.2L 1998 Dodge Ram. I purchased a 6 rib pulley using the online drawings and an external regulator kit. Prior to the conversion, voltage varied from 11-13.5 volts. After the conversion it holds a steady 14 volts.

https://store.alternatorparts.com/pulleys-and-clutch-pulleys.aspx
 

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Randy, that is very strange. I see the rear spacer in place so that keeps the alternator tight to the front of the bracket. That means the alternator should be in the correct position. That only leaves the front pulley. I checked my industrial catalog and it show no spacers behind the drive pulley. It doesn't make sense that it could have operated in the delivery van without tearing up belts. Do a simple test. Get a combination square, probably a 16" would be good. Lay the blade in a groove on the top pulley and see which grove it hits on the alternator. Then reverse the square and check from the alternator pulley. If it hits the same groove going one way but not the other it means one of the pulleys is bent or cocked. If it hits the same groove going both ways then the pulleys are parallel. Might also check between the top and crank pulley. You could have a warped fan pulley.
 

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Discussion Starter #1,145 (Edited)
Char: "Strange," doesn't fully cover it. I have unknown forces acting on me that defy description. Hence things happen frequently that seemingly have no discernible logic attached to them and result in the need to rely on Sheer Luck and other Black Magic to achieve a desirable result. I do fairly well with this, but would prefer simple A-B reasoning to solve problems, but I've got to work with what I've got.

Life goes on and the Steering Gear is being rebuilt and will be back on Monday.

Will take the alternator pulley apart tomorrow and figure out a fix for that.

Randy.
 

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Discussion Starter #1,146 (Edited)
So Steering gear was dropped off Saturday morning and picked up Monday afternoon. $195 complete and has no backlash at all. All seals were completely gone and adjustments were loose. Waiting for new paint to dry and will reinstall tomorrow. That should fix the shimmy problem.

Then on to the alternator problem. Hoping to be able to remove the pulley with it on the engine, will try a 1/4" spacer behind it.

The Tach is in Portland being looked at. And I have to do some tests on the WT and EGT gauges to see if they have gone bad. Inst panel is on the bench so I can't drive the car until the Tach comes back.

Randy
 

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Discussion Starter #1,147 (Edited)
So I reinstalled the Steering Gear today we'll get to testing it tonight maybe.

On another note: The Tach was bad and they found another one that is good and are sending it to me

We'll see how that works when it gets here.

Randy.
 

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Discussion Starter #1,148 (Edited)
I did not know that you have to Bleed your Power Steering System in the first place, and that adding a Hydro Boost to the system complicates that process somewhat more.

I always thought it was self bleeding when you pumped fluid thru the system?,,, guess not. I have been around these things for decades and never heard of this before yesterday.

Have any of you ever heard of this procedure? https://www.youtube.com/watch?v=J51y_9PYXFQ

A lot of wheel turning in this process but I guess it is the correct way to do this procedure. I had never heard of this and have never done anything but hook up the lines fill the pump, start the engine and turn the steering wheel back and forth a bunch of times. My Yellow Jeep had 35 x 15.50 Super Swampers on it (125 lbs each) and I could turn the wheels lock to lock in the rocks with one hand. But apparently I was missing out on alot of power assistance.

However with a Hydro Boost you have to pump the brake pedal to bleed it out as the Accumulator traps air as well..

The whole idea here is to make sure you don't get a bunch of air bubbles trapped in the fluid which come out and cause problems with a spongy pedal and in imprecise steering inputs not to mention less power in the system. This happens as soon as you power up the pump with air in the system.

By pumping fluid thru the system using the Power Steering Gear as the pump (simply turning the steering wheel lock to lock many times) you don't agitate the fluid and trap air in the system. After seeing the internals of the Steering Gear and how it works it becomes obvious why you need to do this as any air in the system decreases the systems efficiency dramatically. It is a Positive Displacement Hydraulic System just like a Brake System.

The process goes like this,
1. Fill the tank with PS fluid and I'm not going to use anything but ATF despite the call for dedicated PS fluid, the reasons given were BS IMHO.
2. Turn the steering wheel lock to lock 5 times.
3. Pump the brake pedal 3 times. You do this to bleed air out of the Accumulator on the Hydro Boost.
4. Refill the reservoir
5. Repeat 40-50 times.
6. Start engine and watch fluid reservoir for air getting stirred up. If none shows you're done.

If you get air then you let the whole thing sit for 1/2 hour and repeat steps 1-4 another 20 or so times and recheck.

You're supposed to do this with the front end off the ground so there is no resistance to the steering . I am doing it with the Pittman Arm disconnected simply because it is off right now and accomplishes the same result..

With my big tires I need everything I can get, so I will be doing this process and will report back the results.

Randy
 

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Randy, ATF and PS fluid are not the same thing and are formulated to do different things. If you're dealing with parts from the late '70's or earlier then they can be substituted for one another. After that things started to change in both fluids and systems. Hydroboost complicates it even more. ATF tends to be detergent in nature. Do you have a filter on the system. It can be built into the pump or in the return line from the steering gear. Hydroboost does not like any kind of dirt. Here's a good article that explains some of the difference. No hype or BS and they aren't selling one over the other. https://carfromjapan.com/article/car-maintenance/can-you-use-transmission-fluid-for-power-steering-pump/ Of course ATF has a lot of different formulas too. For example, Ford's Mercon V is listed for both ATF and PS. Other companies have specific products for each application.
 

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Discussion Starter #1,150 (Edited)
Char: the steering gear was from a early 70's Chevy Truck and the pump came with the Engine and the Van had a Hydroboost. There is also a cooler/filter on the system (the black thing hanging on the grill.) I spent some time last night bleeding the system and it made a huge difference. I've got real "one hand" Power Steering now and the brakes only require a toe to operate. I just got back from a drive and am going to rotate my tires front to rear as I still have some wobble.

I also have to adjust my Drag Link one turn to get the wheel back to the neutral position.

After that I will deal with the Alternator Pulley's position, and see if that fixes the Belt Tracking problem.

I really need to get all these piddly problems resolved so I can move on to bumpers and top install before it gets cold here.

We have two seasons out here, Hot and Cold with tolerable temps about 1 month long on either end. Driving a wide open Jeep in the winter here is not on the menu.

It is pretty cool to drive with the steering working properly it turns much tighter to the right than to the left so a knuckle stop adjustment is going to happen as well.

Back to work.

Randy
 

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Discussion Starter #1,151
So after the tire rotation and drag link adjustment there is almost no wobble at all Jeep is nice to drive. In fact I am going to return the new Godzilla Movie we watched last night to the Red Box after dinner and then go for a drive thru Ojai. It starts to cool off a little after 6:00 PM and its a nice pleasant time to be in an Open Jeep.

Making solid progress.

Randy
 

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... a knuckle stop adjustment is going to happen as well....
Lesson learned the hard way: Make sure that the steering is stopping on the adjustable stop. I had an IH (uses the same steering box, just reverse rotation). One of the steering stops was turned all the way in, so that the box was stopping on the top plate - eventually cracked the box casting at the circle clip grove (that held the top plate in).
 

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Discussion Starter #1,153
thanks Russ,,, will definitely look for that.

Randy
 

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Discussion Starter #1,154
Another Success!

A .200 spacer behind the Alternator Pulley solved the belt tracking issue. The belt tracks perfectly now and the engine runs smoother for some unknown reason.

I have another thing coming that should tame it down even more.

Power Steering is working nicely now and rotating the tires got rid of the wobble. I still need one more half turn on the drag link to center the steering wheel perfectly but that is no big deal. Need to drive it a while to see exactly where the center needs to be.

It is super Humid here right now and I made the mistake of driving around with the A/C on and it pissed all over my carpet on the passenger side. I have to drill a hole thru the firewall for the drain hose before I turn it on again. Kept meaning to do that and like most things like that I forgot about it until it did it's business on the carpet.

Had a good drive around the area tonight, It gets better every time I drive it.

Randy
 

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Discussion Starter #1,155 (Edited)
Long trip today.

Did a 75 mile trip today form Ojai to Ventura to Port Hueneme to Camarillo to Ventura and then home. Took the Freeway to Ventura and buzzed along at what appeared to be 65 MPH. Speedo is not calibrated exactly right yet and the needle wanders around at speed so its indications are more of a "suggestion" than actual fact. Engine is buzzing along at what appears to be above 2000 Rpms, no way to know exactly as the Tach Doesn't work yet. Got nothin' there. The engine is not working very hard to move this vehicle around, and it should last a good long time just spinning with virtually no load on it.

Confirmed the Fan Belt is tracking correctly, and Power Steering has pretty much excluded all the air in the system. The steering is one hand from lock to lock at a dead stop so it is functioning correctly now. No Tire wobble wobble even at 65 MPH. Pulling about 6-8 psi of boost at that speed and more if going into the wind or up a hill.

The TH400 shifts at acceptable points after the machine is fully up to operating temp. It won't upshift into 3rd gear when cold unless I manually shift it from 2nd to 3rd with the stick. After it is warm I can run it in "Drive" and it will shift normally. It's actually quite nice. It cruises nicely in town in 1st and 2nd which is good up to about 40 mph.

I still have to figure out why the OD is not activated, but before I do that I want to rewire it so it only can operate when the key is on. I wired it direct to the battery like the instructions said, but you can shift it when the engine is off and car not moving which is not a good thing.

More work to do on Debugging but steady progress is being made and over all I'm liking the vehicle. It definitely gets attention and the number of Thumbs Up it gets is a nice addition to driving it. When people come up next to me at a light with their windows open they do tend to notice it is a diesel. It's not that loud inside the car even with no top due to the sound proofing I used. I have insulation for the hood as well and that will quiet it down some more. With the top on it should be decent to drive in. Also with bumpers and a top on it will weigh the car down some more and decrease the bounciness and smooth the ride out alot more.

Lots more coming.

Randy
 

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Discussion Starter #1,156 (Edited)
Another Big Success!!!

So last Friday before Labor Day I was looking around Ebay and I searched "4BT Vibration Damper." A bunch came up from a variety of Places and Prices, but one stood out.

It was Cummins Part Number 3958258/3914454 for use on 4B 4BT 6B and 6BT engines. Made in China just like OEM $81.50/ $93.55 shipped, as opposed to from Cummins at $212.50 for the exact same part also made in China. I shipped from Shanghai on Monday and arrived today! not bad for a half a world away. It was even painted black.

It is the same as the one on my 6 BTA in the truck. It weighs 11 lbs 2 oz and is 8" in dia so it clears my A/C drive pulley, took 15 minutes to install.

This fit my application perfectly and the difference was NIGHT and DAY !!!

The part has a Serpentine pulley on the back and used the same bolts as the pulley that was on the engine. Only problem I had was I can't get 100 pounds of torque on the bolts so I will have one of my younger friends reef on it tomorrow. I got probably 80 on them now.

So previously when the engine was at idle out of gear it would shake everything in the Jeep including my butt. In gear is shook the Drivers Side Mirror so bad you could not make out anything in it.

Now it vibrates so much less the mirror is still when at idle and only shakes a little when in gear, like waiting for a light. You can easily read a License Plate in it now, before you couldn't even see the license plate at all.

The car is so much smoother on the road now it is scary. Like I said Night and Day difference.

I am extremely pumped right now having just returned from a Cruise of Downtown Ojai CA where it is in the low 90's right now with 2500% Humidity, and perfect weather for an Open Jeep Ride.

One more thing off the punch list and working my way towards having a very drivable vehicle. The engine was really loving not constantly being shaken silly, and my butt is not vibrating like it was after yesterdays 75 mile trip.

Big win tonight!

Randy
 

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Randy, the harmonic balancer you have works fine on a 6bt but will have little impact on a 4bt. A 4bt does not have harmonics like a 6bt. The only unit that has shown any significant improvement on a 4bt is the one designed for them. That one weighs in the 24-26 lb range. It is a fluid type. Came on marine and some industrial engines. And no, it ain't cheap. The OEM unit from Cummins is probably in the $600 range with the bolts and adapter. The company Fluidampr has them for a good bit less. The stock Cummins unit uses the stock crank pulley. Fluidampr also sell one like that or one with the pulley built in. I'm sort of surprised this one made much change on your engine. Maybe the added mass to the crank helped.
 

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.........It was Cummins Part Number 3958258/3914454 for use on 4B 4BT 6B and 6BT engines. Made in China just like OEM $81.50/ $93.55 shipped, as opposed to from Cummins at $212.50 for the exact same part also made in China...…….It is the same as the one on my 6 BTA in the truck. It weighs 11 lbs 2 oz and is 8" in dia.

This fit my application perfectly and the difference was NIGHT and DAY !!!

The part has a Serpentine pulley on the back and used the same bolts as the pulley that was on the engine.

So previously when the engine was at idle out of gear it would shake everything in the Jeep including my butt. In gear is shook the Drivers Side Mirror so bad you could not make out anything in it.

Now it vibrates so much less the mirror is still when at idle and only shakes a little when in gear, like waiting for a light. You can easily read a License Plate in it now, before you couldn't even see the license plate at all.

The car is so much smoother on the road now it is scary. Like I said Night and Day difference.

Randy

Thanks for sharing that information. I'm glad we now have documentation that the 6BT dampener is effective on the 4BT. I have a dampener from a 1995 Dodge 6BT that I plan to install.
 

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Discussion Starter #1,159 (Edited)
Yes guys the difference was night and day.. This engine seriously vibrated and that vibration was transmitted thruout the entire car.

The balancer didn't eliminate ALL the vibration but it cut it down to a tolerable level mainly at idle and up thru the lower speed range.

The whole reason I did this was because the Fluidampr that they gave me is 9.75 " in dia ( 18-19 lbs) and won't clear my A/C pump pulley. This one is 8" and doesn't interfere at all.

It appears that the pulley that was on the engine is what is used when a large flywheel and clutch assembly is hung on the back. The auto trans applications had this one. This engine was a Cummins Recon and was probably originally from a Manual Trans application, and didn't get swapped during the changeover, just as the TCI Rebuilt Trans wasn't a TH475 like the original probably was. It was a poor rebuild where they didn't put the thrust washers on the main shaft which wiped the case out. It was parted out in exchange for the internal inspection of the TH400 I have now. It got the M Case oil pan but TCI didn't swap the Diesel Governor, which is now lost to time.

Keep in mind that this engine has a fairly substantial mass (Diesel Torque Converter) hung on the back and whereas it is not as heavy as the Flywheel and Clutch Assembly, it is still there and upping the mass on the other end did help tame the vibration down to a very tolerable level. I don't have to put the trans in neutral at a light now. before it shook pretty bad at stop lights.

Please understand,,,, this was immediately noticeable as soon as I fired the engine after installation! It was not some "slight decrease in the vibration." It was dramatic. I was standing beside the Jeep on the drivers side and started the engine from outside in order to check the fan belt tracking. Ordinarily the Drivers Side Mirror would have been shaking back and forth wildly and the entire car would be vibrating so no matter where you touched it you could definitely feel the vibration.. Not so this time.

I wish I would have videoed the before and after, but I was too hopped up on installing the new part, and forgot entirely about doing it, so I apologize for that short coming..

I will try to post a video of the car now,,, later today.

The pics show the perfect belt alignment now after the .200 spacer was installed.

Randy
 

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Discussion Starter #1,160
Another Big Success!!!

Well I got another win on the board today. Isspro came up with the fix for my Tachometer. It was simple and it only took a few minutes to change the wiring slightly and BINGO!

So I went out tonight and drove around watching the tach and speedo.

When cold I have 900 rpms at idle. When warmed it is 1000 rpms. I need to lower that a little and now since I know how fast it is going I can do that .

1800 rpms appears to be 50-55 mph. 2200 appears to be around 65-70 mph. The Speedo does wander a bit so it is more of a suggestion of the speed and not sure it's calibrated exactly right yet.

This is all in Direct Not O/D as I haven't fixed the O/D wiring yet. At least I hope it's not in O/D? not totally sure on that until I get the switch working and can shift it.

Another thing off the punch list! Feeling good tonight as i have been fighting this issue for over a month.

Randy
 
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