TDC help

[Arizona_928]

well seting TDC today, i set the the cam. moved to crank insection hole, and found this



and noticed it isn't anywhere near the OT mark. i know the PO has been in their before. and prob messed it up. how would i set it to this? really afraid to bend valves, so would you advise to set TDC on the crank, then set the cam??

http://clarks-garage.com/shop-manual/eng-13.htm


thanks Levi

[Majin325]

What I did to set mine was get the cam in the general area of TDC and looked down the hole moving the crank slowly. The flywheel rotates quite a bit of distance with hardly any movement and is easy to go past the OT mark. The marks on mine didn't line up perfectly but were very close.

[Techno Duck]

Its possible the timing is off a little. You can reset it by hand by carefully rotating the cam or crank a little at a time until they line up. Stick a wooden dowel through the #1 spark plug hole to get a good idea when its at TDC, then verify your at the correct TDC with the marks on the flywheel. I cant really tell by the picture how far off it is though.

Dont sweat it, its not to bad to reset it. I mistakenly forgot to tighten the spring tensioner once and the timing belt slipped a few teeth when i turned it over by hand. I had to reset the timing on the car by hand. I basically turned the crank a few degrees, then the cam a few degrees..and kept doing this until i got them to line up again. Just work very slowly and stop if you feel resistance. This was all done about 5 years ago when i knew nothing about working on cars...so you can imagine how nervous i was.

When you think you have it all together, turn the engine over a few times by hand to verify you have it set right.

Another good tip is to take out all 4 spark plugs so the engine rotates easier.

Did the car run weird or did you have trouble passing emissions with the timing off like that?

[m73m95]

it kind of depends on where you were turning the engine from....There is a little bit of slack in the belt, even at the correct tension.

spin the engine with a socket on the crank pully, clockwise untill the timing mark on the cam is lined up....then look through the hole in the bell housing...I thought mine was off too, untill I put the correct tension on the belt.

[Schumi]

The flywheel rotates twice for every time the cam rotates once. To be a true TDC (#1 is on beginning of intake stroke) the cam marks have to line up right? Why do people mess with the crank marks when the cam mark is so easy to read? Is the cam mark not accurate enough or something?

[m73m95]

its not accurate enough of you're setting the belt tension.

[Arizona_928]

Originally Posted by Techno Duck

Did the car run weird

yeah made a clunk, clunk, clunk sound....

ohh what's a interference engine?

[speedracing944]

Maybe you skipped teeth and now the valves are bent which might be causing the clunk clunk sound. Get the flywheel to TDC and then look how many teeth you are off on your cam sprocket. Report back.

Speedy

[Arizona_928]

I was able to get a friend to help me out, and when i lined up the mark on the crank, the cam mark was off. by a lot.....

[968rz]

Originally Posted by AZ_porschekid

ohh what's a interference engine?

That's when the valves and the piston both use the same area, if the cam to crank timing is off too much the piston comes up while the valves are still down and they hit each other, baaaaaaaad

[944 Ecology]

Originally Posted by AZ_porschekid

I was able to get a friend to help me out, and when i lined up the mark on the crank, the cam mark was off. by a lot.....

Yep, it's out by 180 degrees. Since the crank turns twice when the cam turns once, all you have to do is rotate the crank one more revolution and it should be pretty close.