PhilW 317 Report post Posted June 9 Im beginning to wonder if my TDC marks on the flywheel are correct. I dis read someone else had this issue. Someone has centre punched a mark 10mm or so to the right of TDC flywheel mark. To be 100% i suppose sticking a welding rod into the cylinder and finding its highest point would confirm if i am right. Theres got to be a reason for the centre dot and im not running very well. Carbs are popping a bit. Thanks for your thoughts Quote Share this post Link to post Share on other sites
Barrykearley 5,087 Report post Posted June 9 There’s a known issue of accuracy between flywheel indicators and bottom pulley indicators. Only by checking for TDC will you know Quote Share this post Link to post Share on other sites
PhilW 317 Report post Posted June 9 So welding rod in the pot Barry must be the only sure fire way? Quote Share this post Link to post Share on other sites
drdoom 112 Report post Posted June 9 Welding rod in the pot, as long as it is firmly connected to a dial indicator instrument. The motion of piston near TDC becomes vague so not useful in describing directly. The method is to bracket an angular figure both sides of TDC via equal measurements of piston displacement. TDC will be established as the mid point between these, made possible with confidence only by use of a D.I. gauge. Cheers 1 Quote Share this post Link to post Share on other sites
Sparky 1,946 Report post Posted June 9 In 40 years, I've seen one incorrectly marked flywheel, and it wasn't a Lotus. Quote Share this post Link to post Share on other sites
C43 41 Report post Posted June 9 My Esprit was wrong. I spent ages trying to get the timing right and could not work out why the figures I was getting was so far away form the book figures. It's only when I took the car to a local specialist did we find out it was wrong. I guess the engine had been rebuilt wrong. Quote Share this post Link to post Share on other sites
Sparky 1,946 Report post Posted June 9 But what exactly was wrong? Quote Share this post Link to post Share on other sites
910Esprit 363 1 Vehicles Report post Posted June 9 You also have a timing mark on the front pulley, If they both align to TDC at the same point, it wil be pretty certain your flywheel timing marks are correct Quote Share this post Link to post Share on other sites
Sparky 1,946 Report post Posted June 9 And if they don't (ask @Trevsked) I'll bet the farm the flywheel is the correct one. 1 Quote Share this post Link to post Share on other sites
C43 41 Report post Posted June 10 On mine the timing marks on the flywheel were out. It was a right PITA as they had been nicely highlighted by the previous owner but were about 1 spline out s far as I could work out. As you guys say the only way to tell for sure is take plug out of #1 cylinder and find TDC with a length of wire and a DTI. If you approach it from both directions a few times you should get an accurate reading. good luck C43 Quote Share this post Link to post Share on other sites
ekwan 28 Report post Posted June 12 On 09/06/2019 at 20:05, Barrykearley said: There’s a known issue of accuracy between flywheel indicators and bottom pulley indicators. Only by checking for TDC will you know Which is more consistent though, and by what percentage? Quote Share this post Link to post Share on other sites
