Hi Im new here.......Just obtained a non running C25 1967 doing various check prior to any major strip down which Im trying to avoid..can anyone confirm if the valve rockers ie inlet and exhaust are supposed to be Identical? ie the arm with the pad on that touches the valve as when removed and laid on a flat surface the inlet arm sits slightly higher than the exhaust? is this due to valve geometry etc as adjusted with the eccentric cam. (had issues with leaking compression and this is a start.
Also, timing marks on rotor don't line up with TDC etc? head is off and I can clearly find TDC and before TDC but marks are way off. any info much appreciated, Cheers
On a different note check the oil pumped isn't seized before you kick it over.
okede
Hi, I hope that I am understanding your message correctly. The mark on the rota is help set the timing 37-38 degrees before TDC at full advance. However, it is best to check that this is accurate with a timing disc. I checked mine using an old spark plug; I removed the electrode and inserted a metal rod, aluminium is best so not to damage the top of the piston, bolt or glue this in position through the centre of the plug. Put the adapted plug into the cylinder head. Turn the engine clockwise until the piston is stopped by the rod. Attach a 360 timing disc to centre of the rotor nut (you can use those small powerful magnets for this). Fashion a pointer (a bit of wire wrapped around on the the primary chain case holding down screws will do) and set the timing disc to zero degrees. Turn the engine anticlockwise (the disc should turn freely with the rotor) until the piston again is stopped by the adapted plug and note the reading on the timing disc. If this reads, say, 270 degrees; 360 minus 270 equals 90. That is the measured angle of the crankshaft between the points when the piston was stopped in the bore. If you halve this figure (45 degrees), reset the timing disc to zero, remove the plug and then rotate the engine (so the piston is rising) 45 degrees you will have found the absolute TDC. Reset the timing disc again to zero and rotate the engine (backward, clockwise as you look at the rotor) to 38 degrees and check the timing mark on the rotor. If it seems out mark with a pencil or another non-permanent marker, then recheck using the method above and if it still looks wrong make a new mark on the rotor; I used a sharp centre punch and then put a drop of paint in the hole, white is best. This is the mark you then use for setting the timing.
I do hope that this is helpful and that I have not misunderstood your message otherwise I have wasted both of our time :-)
Rev Kev