PDA

View Full Version : need help finding Top Dead Center



beckley
02-24-2007, 02:12 PM
i have an 87 e30 that i would like to adjust the valves on. however, i can't figure out how to check to make sure that cylinder number 1 is at TDC without having access to the camshaft timing sprocket (which is located behind the timing belt cover). i know that the O/T mark on the crankshaft pulley timing wheel needs to be aligned at the same time to ensure that cylinder number 6 isn't at TDC and not cylinder number 1.

could someone who is showing up to the tech session at Funktion show me how to do this or some other way to check that cylinder 1 is at TDC.

thanks,
jim

odortiz
02-24-2007, 08:44 PM
you can look for a mark on the crank pulley for a TDC mark. this only means crank is TDC. to see if #1 is TDC, look at the cam lobes. all the valves should be closed on #1

mlytle
02-25-2007, 11:54 AM
pull spark plug and stick a really long screwdriver down into the cylinder. slowly rotate engine until you find the point that the screw driver stops coming "up" and the valves are the right open/closed configuration.

put a mark on the screwdriver at the high point. you now have a special tool for finding out when all the rest of the cyl's are at the same point....

beckley
02-25-2007, 02:30 PM
beats pulling the timing belt cover! thanks, much.

jim

ErikT
02-26-2007, 09:44 AM
http://www.pelicanparts.com/BMW/techarticles/101-Projects-20-E30-Timing-Belt/101-Projects-20-E30-Timing-Belt.htm

If you haven't gotten it yet, you should be able to find it here. Plenty of good E30 maint. tips.

bmwracr
02-26-2007, 05:54 PM
Best way to know when valve cover is off is when # 6 cylinder is on overlap. Hope this helps

dan

beckley
02-26-2007, 08:47 PM
thanks to all. i think i can nuke it out now. if not, i shouldn't be messing around under the hood! now, how to actually adjust the valves...:eek:. just kidding.

jim

Bob
02-28-2007, 06:14 PM
WHY TDC ? Adjust your clearances as each cam lobe is opposite the rocker, pushing car in 5th gear works best, write down each # as you progress, or you'll lose track!