larryp Posted November 20, 2006 Share Posted November 20, 2006 Replaced timing belt, idler pulleys, and water pump this weekend. Boy what a job. When the magic moment came to start her up, i held my breath and she started just fine :D but... there was a loud tapping coming from the passenger side distributor cover. Took it for a spin of about a mile and the tapping disappeared. Running smooth as a clock. This morning when i started it up, same thing. Drove it to work and within 2-3 miles the tapping disappeared. Definately coming from the pass. side distributor area. Other than that it's very smooth and quiet. Car has 212K. Any ideas? Quote Link to comment Share on other sites More sharing options...
RFeldes Posted November 20, 2006 Share Posted November 20, 2006 Could be high voltage arcing which subsides when the car warms up due to expansion...I would pull that cover and inspect the plug wires... Quote Link to comment Share on other sites More sharing options...
larryp Posted November 20, 2006 Author Share Posted November 20, 2006 Could be high voltage arcing which subsides when the car warms up due to expansion...I would pull that cover and inspect the plug wires... Thanks. I'll check it out. Quote Link to comment Share on other sites More sharing options...
93ls400walt Posted November 27, 2006 Share Posted November 27, 2006 Give us an update. And please give any tips or tricks to changing all of these parts. I am planning on changing mine in the near furtue. And I want ot do it myself. Thank, Walt Quote Link to comment Share on other sites More sharing options...
larryp Posted November 28, 2006 Author Share Posted November 28, 2006 Tapping has not reappeared. Now have 400 miles since TB repl and car runs great. Figure i'll replace dist cap, rotor, and plug wires in the near future just to be safe. All are probably original. TB and water pump replacement is a major job as you know. But thanks to the instructions from Lexls and being careful and patient with the project, it's doable for a competent DIY-er. Be sure to bag all nuts and bolts and label the bag so you'll know where they go when it's time to put back together (i had no leftover bolts :D ). One thing that did stump me for a few minutes was after installing the new belt you are supposed to rotate crank shaft 2 times to make sure the marks line back up. I was thinking this referred to the marks on the timing belt itself matching with the pulley marks - but what it really means is that all the pulley marks line up with their reference marks on the engine (cost me an extra 45 minutes to figure this out since i didn't read the instructions close enough ). Very happy to have this repair behind me! Let me know if you have any other questions. THanks. Quote Link to comment Share on other sites More sharing options...
Threadcutter Posted November 28, 2006 Share Posted November 28, 2006 One thing that did stump me for a few minutes was after installing the new belt you are supposed to rotate crank shaft 2 times to make sure the marks line back up. I was thinking this referred to the marks on the timing belt itself matching with the pulley marks - but what it really means is that all the pulley marks line up with their reference marks on the engine. Larry: Don't feel bad, it really isn't clear....... I think that all the marks (including the marks on the timing belt) will all line up at "n + 1" revolutions of the crankshaft.......where "n" = number of teeth on the timing belt. However, I've never remotely had enough patience to attempt to prove whether or not it is true. Maybe there's a math genius lurking around this board that can confirm this for us (?)..... but what it really means is that all the pulley marks line up with their reference marks on the engine. If you got this to happen, you're in good shape! (this can/will happen even if you don't have the timing belt marks aligned properly). In other words, if the mark on the belt is off by two teeth for the right hand cam, as long as the mark(s) for the left hand cam and the crank are also off by two teeth (in the same direction), you're still OK. The marks are there just for convenience, they are not an "absolute".......Having gone through the same procedure, it makes perfect sense in hindsight. Quote Link to comment Share on other sites More sharing options...
larryp Posted November 28, 2006 Author Share Posted November 28, 2006 Larry: Don't feel bad, it really isn't clear....... I think that all the marks (including the marks on the timing belt) will all line up at "n + 1" revolutions of the crankshaft.......where "n" = number of teeth on the timing belt. However, I've never remotely had enough patience to attempt to prove whether or not it is true. Maybe there's a math genius lurking around this board that can confirm this for us (?)..... :whistles: I can tell you that n is a number a lot larger than 10 Quote Link to comment Share on other sites More sharing options...
wsd Posted March 24, 2007 Share Posted March 24, 2007 Back to that tapping sound, I had that same problem after replacing my timing belt, except mine was on the drivers’ side. I thought it sounded like it was coming from the distributor rotor or possibly that tab on the cam pulley hitting the cam position sensor. I was a little depressed with the notion of having to tear it all apart again or the damage of some expensive Lexus part, so it sat for two days. It turned out to be simply the rubber gasket of the timing belt cover hanging loose and being hit by the cam pulley tab. A little weather strip adhesive made sure it wouldn’t happen again. Fixed in less than 15 minutes. :) Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.