Fish13 Posted October 25, 2009 Share Posted October 25, 2009 Hi Guys, Apologies for what may sound basic, but I know that the timing mark on a lot of Rangie's is far from accurate - how can you find top dead centre (for numpties) please? I had the dizzy out and it moved so now have to find TDC on the rangie and put the dizzy back in with the rotor arm pointing to lead no. 1 correct? It's a 3.5 in a 1988 EFi. Cheers for the help! Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted October 25, 2009 Share Posted October 25, 2009 For TDC you can be 50 / 50 in being correct as TDC will appear on the compression stroke (what you do want) and also the exhaust stroke (180 degreses out), An easy way is Remove passenger rocker, and No 1 spark plug, use a long wodden 5mm "Stick" pop down the plug hole onto the pistobn crown, then rotate the engine by hand and watch the TC Marks on the Crank pulley AND the 2 rockers as it all comes around. When the pointer is at TDC and the stick stops coming up and starts to drop that TDC or one of them, if at the same time BOTH Rockers are fully closed then that the TDC you wnat, if one rocker (exhaust) is open your 180 degrees out. The other benifit of the stick in the piston method is you also get to see how close you extaernal TDC marker and pointer is in true relation to the piston at TDC, I have seen many markers be 2 3 or up to 6 degrees out ! HTH NIge Quote Link to comment Share on other sites More sharing options...
Fish13 Posted October 25, 2009 Author Share Posted October 25, 2009 That's exactly what I was after thanks Nige. If I'm 180 degrees out, will engine run? Or just run like a bag of spanners? When I've got top dead centre on the engine, then put dizzy in (currently out of engine at the moment), where the rotor arm then points - I make plug lead no. 1 when I put the cap back on, is that right? Cheers! Fish. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted October 25, 2009 Share Posted October 25, 2009 Not Run, more 'Pop + Bang + try to start' - but won't Nige Quote Link to comment Share on other sites More sharing options...
Fish13 Posted October 25, 2009 Author Share Posted October 25, 2009 Thanks Nige - what about the rotor arm query, can you clarify that for me? Cheers, Fish. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted October 25, 2009 Share Posted October 25, 2009 Yep at TDC or a tad towards static timing pop in the Dizzy so that No 1 plug lead on the dizzy is over the riotor arm Sometimes you'll need to move the oil pump drive about so it all lines up, sometimes you need to over set it so it slots as the gear goes in and then all lines up Nige Quote Link to comment Share on other sites More sharing options...
steve_d Posted October 25, 2009 Share Posted October 25, 2009 If you want to very accurately find TDC then take an old spark plug and smash out the centre. Fit a bolt or piece of threaded rod through with a nut either side so that you can adjust how much pokes down into the cylinder. Make the end of the rod nice and rounded. Fit into the spark plug hole. Very gently rotate the engine until the piston reaches your stop. Mark the front pulley at the timing pointer. Rotate the engine the other way until it again reaches your stop. Mark the pulley. True TDC is half way between your marks. If your stop is too long the marks you make will be a long way apart and make life difficult so adjust the length of your stop so the piston gets nice and close to the top of its travel. Steve Quote Link to comment Share on other sites More sharing options...
paintman Posted October 26, 2009 Share Posted October 26, 2009 Don't forget that you need to position the rotor arm about 30 degrees anti-clockwise before No1 before putting the dizzy in as when the gears mesh the rotor will rotate due to the gears being cut at an angle. Whilst you could make any lead No1 and then set the rest from there, why not have it right from the outset? Quote Link to comment Share on other sites More sharing options...
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