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sonoronos

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Everything posted by sonoronos

  1. A good galvanizer should be able to string your frame up with paint on it. They will drop it in the Zinc kettle prior to beginning the galvanizing process, literally burning off anything that isn't steel. This is even more true if the galvanizer is running their pot for a high-temp galvanizing line. Some places run actual burn-off ovens.
  2. The only way you'll know is if you fit the trim to your sides and see if they line up. If they don't, then don't worry about it - just run it without the trim.
  3. Sorry, I just understood what John was getting at. When I wrote "the sole purpose of the DC joint is to reduce U-Joint angles", I was incorrect, the DC joint's primary purpose is as a Constant Velocity joint - the reduction in u-joint angles is important, but incidental.
  4. Thanks John The only other thing I want to add is that despite the combination of two U-joints and centering ball performing similarly to a constant velocity joint, the two U-joints in the Double-Cardan joint still experience sinusoidal acceleration individually. Therefore, there is still a U-Joint angle dependent rotational torque generated by and through the double-cardan joint. This rotational torque is one of the main components of wear in the centering ball (which John mentioned earlier.) In practice, of course, the idealized CV-Joint created by the double-cardan will become less ideal with wear of its components and also the U-Joint angle. That is, the sinusoidal cancellation of the double-cardan joint is a mathematical idealization. In practice, the Rzeppa-style joint (as in a steering CV joint) is closer to ideal, although it has its own problems (namely reduced strength relative to the operating angle, and of course usually less maximum operating angle than the double/dual cardan.) But I do want to caution that I am not describing one as better than the others. These are all tools to fix problems, some may be appropriate in some cases more so than others. That video you posted is nice but I think can be misunderstood to imply that the sinusoidal cancellation somehow completely nullifies the U-Joint angle problem. The computer graphics is calm, but the reality of the "fluctuating output" can be quite energetic depending on the U-Joint angle.
  5. I'll try to answer your question: "How can double cardan shaft help reduce vibration in a defender ?" First, your question is a logical conflation of two totally different things: Why do driveshafts vibrate and What are double cardan shafts. These are two totally different questions and conflation of these two concepts will lead to confusion. Let's answer your two totall different questions independently: What are DC Shafts: 1. In total fact, Double Cardan Shafts have one and only one purpose: They exist only to reduce the U-Joint operating angles in a driveshaft. 2. By reducing the U-Joint operating angles, you reduce the issues related to non-zero U-Joint operating angles. Why do driveshafts vibrate: 1. Imbalance 2. Out of phase operation 3. U-Joint angle. Imagine, for a moment, a perfectly balanced, in-phase driveshaft operating at a 0 degree U-Joint angle. That is, the driveshaft is perfectly inline, straight, with no bends. Imagine that the driveshaft is accelerated to 6000rpm. How do you feel about the vibrations of that system? Now Imagine, for a moment, that this driveshaft spinning at 6000rpm is aligned so that the U-Joints are now operating at a hypothetical 45 degrees. How do you feel, by gut instinct, about the smoothness of the operation of the 45 degree driveshaft at that speed? The truth is, that driveshaft operating at 45 degrees is experiencing incredible rotational acceleration forces upon each rotation. One every rotation, each joint is constantly accelerating and decelerating, applying a torque to the U-joint and the driveshaft (think of cracking a whip.) The driveshaft and U-Joints have to take these torques and then transfer them to the next U-Joint. These forces are massive, the very material of the driveshaft will experience twisting and bending. Given these huge forces, which are enough to destroy the U-Joints and driveshaft itself given enough strain, how do you feel about the total vibration of the system, despite the fact that the driveshaft was balanced and perfectly in phase? Do you feel there would be some vibration? Now, imagine reducing that U-Joint angle to 27 degrees. What do you think happens to the rotational acceleration forces of that U-Joint? Are they reduced? If they are reduced, do you feel it may contribute to a reduction in vibration? I hope in this example you have found an answer.
  6. Does anyone know if these bronze washers on my 200tdi are removable? This is from an early 200tdi, all original. These injectors haven't seen the light of day since they left the factory. They seem to be much thicker than the replacement washers and lack the crush area that are on the replacement washers. Are these supposed to be removable? Mine are all truly well and stuck and I don't want to force or deform them if they are meant to remain there.
  7. I went back under the truck and used a micrometer this time to measure hole depths. The actual hole depths vary with the shallowest being 22.50mm and the deepest being 23.74mm. Not sure why they vary so much, but since the oil pan itself is approximately ~1.96mm thick, I guess they toleranced it. Funny that 22.50 + 1.96mm is 24.46mm. Per your recommendation, I've updated the photo annotations to use the workshop value of 25mm, but I guess if anyone in the future tries to tighten a screw and it doesn't go flush, then feel free to go down to a 20mm And just to show that i'm not imagining things, here are the screws that came off my factory engine.
  8. thanks everyone, john you're spot on. I've attached my own measurements to this post as well, hope these all serve some purpose in the future Note that two of the 20mm screw holes are actually quite a bit deeper than 20mm (one is approximately 50mm deep, and the other goes completely through the ladder frame into the engine. The rest are thread-bottomed at 20mm and will not accept a longer bolt.
  9. Update: I got replacement slipper pads from Ashcroft's and replacement parts from Carddocks. Rebuilt my gearbox in 2014. The gearbox has been running strong ever since. The reason why this happened to me was that I had a habit of resting my hand on my gear lever while in 4th gear. Doing this rapidly wears out the clutch fork and baulk ring. Once the baulk ring wears out, the synchro sleeve will over-travel and the slipper pads will jam the synchro sleeve. I don't do that anymore
  10. thanks folks - I'll do the drill-bit measure thing tonight and post up the results. Looks like my question was a bit esoteric.
  11. Hello good folks, The 200tdi sump pan bolts number as follows: 2x25mm 6x20mm 12x60mm for a total of 20. does anyone have a reference or know which length bolts go where? I have attached a photo of my sump pan for reference.
  12. Love this thread, thank you so much for the information. I am doing a head job on my 200tdi now...not nearly the full rebuild you have done! I have a question about the headgasket: 1. What was the original headgasket that was installed on your truck (when you removed the head)? Was it an MLS headgasket? 2. Is there any particular reason you went with the composite headgasket on your rebuild as opposed to the MLS? 3. Do you have any idea about how many miles the composite type headgasket will last (in miles)? Do you think it will be as durable as the original headgasket that was in your truck? As you may surmise, I'm trying to decide between using the MLS headgasket (Reinz) or the Composite type (Elring)
  13. Hello...I'm suffering the same issue as the pictures attached show... Quagmire, did you find out the long term solution to this? How did you end up fixing this? New baulk rings, slippers, and springs? Was this a problem with input shaft freeplay?
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