The V8 Owners Forum -

my timing marks seem to be way out when at tdc, whats the best way to check for tdc? iv tried most ways, but wondered whats the most accurate.

If the engine is actually in one piece then the only real option is to use the piston dead stop method. You can make a dead stop using a spark plug.

Check out this gumph, there is a picture of the one that I made

http://how-to-build-a-pilgrim-sumo.wiki ... by-members

I can remember if I explained how to use the dead stop in the article above, if not there most be loads of info on the web.

iv checked and double checked and im sure its very close, it certainly runs and sounds ok. I also spoke to you a while back about my eddy 500 running rich, i changed the jets, rods and springs to what you suggested, its still rich, plugs were all sooty, im using the 360 offenhauser manifold, i looked at you article about the setting up, still not sure if im doing it right.

sorry to change the subject here and use wrong forum for this.

shawser wrote:iv checked and double checked and im sure its very close, it certainly runs and sounds ok. I also spoke to you a while back about my eddy 500 running rich, i changed the jets, rods and springs to what you suggested, its still rich, plugs were all sooty, im using the 360 offenhauser manifold, i looked at you article about the setting up, still not sure if im doing it right.

sorry to change the subject here and use wrong forum for this.

I guess at the end of the day you have to calibrate the carb to suit your engine, I can not really calibrate an engine over the web!

I have come across a few cars where the air filter lid is way too close to the top of the carb, this will always mess up the setting up of the carb.

Fouled plugs can be two things. Poor spark, or rich mixture ( or running too cold plugs )

I guess that's 3 things lol

And dont guess mixtures, use some sort of mixture device. Be it a wideband, gas analyser, or at a push even a crappy narrowband can be of some use.

shawser wrote:my timing marks seem to be way out when at tdc, whats the best way to check for tdc? iv tried most ways, but wondered whats the most accurate.

This is the method I use;
If you want a bit more accuracy .. drill out an old spark plug big enough to take a bit of welding rod (about 5" long seems to work well) bend the end of the welding rod over so it can't fall down the hole (in case you made it too short!) then turn the engine over by hand and watch the rod. If you want absolute accuracy (not really necessary for setting tappets) then put a mark or tape on the rod say 5mm down from where you think the highest point is. Rotate the engine until the mark appears. Mark the pulley against the TDC marker on the front cover, now continue to rotate until the mark on the rod comes back down to the same position .. mark the pulley again .. TDC is precisely half way between the two marks on the pulley.

You dont have to use a spark plug either .. some others have suggested using a compression tester nipple .. as long as it goes in the plug hole and holds things fairly level it will be fine.
I have had a number of front pulleys where the damper has slipped by the way .. this makes the TDC mark on the pulley completely wrong. It doesn't affect the engine, but it means when you check the timing your reference point is wrong and therefore the figures are wrong. If it has moved, consider a replacement pulley or make a mark on the centre hub of the pulley and ignore the damper mark.