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Everything posted by bunkhouse

  1. I've never seen a release bearing that wasn't smooth, not that it has to be if it fits properly into the diaphragm tangs. Seems like one might hear an occasional click when pressing on the clutch pedal as the bearing meshes with the diaphragm. I'd love to hear the theory behind this supposed improvement. Just had another thought. Is it possible it's supposed to stay meshed with the diaphragm and spin all the time? Which would mean reversing your adjustment.
  2. There's a flat stop screw on the bottom that can be removed. It prevents the mixture screws (jets) from being removed.
  3. Here's the simplest method for checking float levels I've found. The fuel level should be 3/8" below the carb bridge. Remove the carb domes and pistons. Turn the mixture screws and raise the jets to their top position. Now turn the mixture screws 9 1/2 - 10 turns down. (9 5/8 turns is 3/8") The fuel level should be close to the top of the jet. It doesn't have to be exact, close is good enough. Re-adjust the mixture screws to app. 2 1/2 - 3 turns down from their uppermost position.
  4. I can confirm they're not US Indy wheels. Mine have the brand name on the inside. They could possibly be Anson Sprints.
  5. I've used a smashed piece of copper pipe to back up small holes. I like the idea of a magnet to hold it in place.
  6. I'd do a compression test to on all cylinders first. There shouldn't be water in any of the cylinders.
  7. The noise sounds like a bad bearing to me.
  8. The drop tests don't show any serious anomalies, IMO. A few more questions. Did it run well prior to the carb rebuild? Have you balanced the carbs? A better method for reading the plugs is to drive it until it starts to cut out, kick in the clutch, shut it off and then pull a couple of plugs before it idles. My gut feeling is the poor performance under load is caused by lack of fuel but judging by the air filter info it would seem to be the opposite, lack of air or too much fuel. You may want to run this problem by the folks at classiczcars.com. I'm Mark Maras over there.
  9. It would seem that the air filters are at fault. If that's true they have to be affecting the carbs in some way. Engine off, lift both carb pistons to the top. There should be considerable resistance but it should feel even. No lumps or bumps. Now let them drop at the same time. They should both hit the bottom with an audible clunk at close to the same time. If the drop rate is substantially different, swap the pistons and test again. The other drop test, tests the rising rate. Remove the domes and pistons. Tape (masking) all the holes in the bottom of the pistons. Place the domes upside down resting in the tops of something like coffee cups. Place both pistons in the domes at the top (equal heights) and drop them at the same time. If the drop rates are substantially different, swap the pistons and test them again.
  10. Pull a spark plug or two and report back about the color. Pics are better.
  11. I believe is was called a differential counterweight. It's purpose was to lessen or eliminate the clunk when the front of the differential raises during acceleration.
  12. The next thing I'd check is the float levels. The fuel level should be 3/8" below the carb bridge. That's 9.52 mms. The nozzle adjustment screw raises or lowers the nozzle 1 mm per turn. Remove the domes and pistons, raise the nozzles up to the top and lower them 9 1/2 turns. The proper fuel level should be at the top of the nozzle give or take a half a turn.
  13. I don't have any recommendations but what are the fuel delivery issues?
  14. I use a 3'-4' piece of garden hose as a stethoscope. You'll be able to poke it into tight areas while holding it to one ear and pinpoint the sound. I noticed the transmission twitching in unison with the click clack noise. Be sure to check that for the source of the problem.
  15. Which carbs does it have on it now? Flat tops or round tops and what seems to be the problem?
  16. A few more questions. Was the throttle wide open during the test? All the spark plugs out? Screw-in connection on the gauge or rubber cone? Rubber hose used on the gauge and the length vs. metal tubing? Did you turn the engine over until the highest reading was obtained? I'd like to see it somewhere in the 165-170 range but 160ish is darned close and any, or a combination of the variables mentioned above could lower the readings slightly. Also I'm not an expert on all the compression ratios throughout the years. Were any of the cylinders considerably lower than the others is what you really want to know. If all the cylinders are within 10% of each other I'd look elsewhere for the oil consumption. The valve guide seals are notorious for going bad and fouling plugs.
  17. Before you assume it needs a complete rebuild, know that these blocks last a long time. I've seen these engines with over 100,000 miles and the bore hone marks are still visible. A common cause of excess oil usage, aside from leaks, is bad valve guide seals. These can be replaced without removing the head or cam. Have you re-checked the valve lash and done a wet and dry compression test to confirm it needs a rebuild?
  18. Did you hold the throttle wide open during the tests? If not, retest and turn the engine over throttle wide open, until the c. gauge needle doesn't go any higher. Then put a tablespoon or so of oil in each cylinder and retest. If the compression raises significantly during the wet test, it means the compression is escaping past the rings. If the compression stays about the same the problem is in the valves.
  19. A quick test for water in the oil is put one drop of the oil on hot (+ 212 f. ) metal. A hot exhaust manifold will work, If the drop of oil smokes, it's pure oil. If it smokes and sizzles, the sizzle is caused by water.
  20. I'd start with a compression test. and check the spark plugs for water fouling. I'm not familiar with the term "bag of spanners" but I'm going to assume it's not a good thing and there is a lot of valve lash noise as well as poor running. It would be a good idea to reset the valve lash prior to the compression test.
  21. Get rid of any and all rust ASAP and keep an eye on any new spots. The sheet metal on these cars is thin and it doesn't take long for rust to eat holes in it. Beautiful Z. 1970 0r 71? It's identical to my first Z, right down to the wheels. If you're going to leave it stock checkout classiczcars.com. They tend to focus on original equipment and problems.
  22. Check over at classiczcars.com. There are many people over there that help with stock 280 injection problems.
  23. Next time you fire it up watch the carb pistons to see if they raise to the same height.
  24. Raise both pistons with your fingers and let them drop. You should feel considerable resistance when raising them and they should both fall at the same rate and hit bottom at nearly same time.
  25. Two interesting problems. Plugs are black, idle is too high. Jonbill is correct about too much air causing the high idle and it must be getting too much fuel judging by the plug color. Describe your carb rebuild. What did you take apart and reassemble? Did you interchange any parts from one carb to the other?
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