Timing Woes!

[mark95turbo]

Well I just put a new head on my car and after I had everything installed I was checking everything over and realized that the t-belt tensioner seemed to be shot. So I bought a new tensioner to install. The only problem is that while I was torquing the cams to get the motor at TDC before taking the belt off the exhaust cam jumped a whole lobe. I had to take the belt off to get the cams ligned up again but now how do I get the motor back at TDC? Should I try and put the belt back on as closely as possible and turn it to TDC? Should I crank the cams a few teeth then the crank a tooth working my way back to TDC without the belt on then put the belt on? Do I have to take the head off again and put everything at TDC while its apart? Thanks!

 

[mark95turbo]

I just realized that I cant take the head off unless its at TDC to avoid bending the valves. Also, just FYI, the cams are at almost exactly 180 degrees from TDC. I thought I rememberd reading that they are all closed at this time also? TIA!

 

[BUCK]

Using a rod thru the Spark plug holes verify that the Inner 2 Pistons are NOT at TDC - Slowly put the Cam Marks in Time as close as possible - Check where the Pistons are via the Spark Plug Hole & a long rod - Move the Crank in WHATEVER direction you need to in order for the Center Pistoms to go down & the Outer (#1 & 4) to come up to TDC.

Generally you will have to bias the Exhaust Cam OUT OF TIME 1 TOOTH COUNTER-CLOCKWISE when you initially install the T Belt - When you tension the belt the Exhaust Cam will roll back INTO TIME. Use the Grenade Pin In the new Tensioner to Set The T/belt Tension.

 

[mark95turbo]

Thanks for the quick reply Buck! I'm a small amount confused though. Basically what I'm trying to do is get the pistons at TDC without the tuiming mark being correct? Then im putting the cams at 180 degees from TDC and putting the blet on?? I put the cams at exactly 180 degees from TDC and took the spark plugs out. When I looked into the chamber I can see that the outer pistons are almost at TDC and the middle pistons are almost all the way down. I'm assuming that when the cams are 180 off that the valves are closed and that the motor is at TDC again correct?

 

[BUCK]

MY NOTES IN CAPS FOR CLARITY...

Thanks for the quick reply Buck! YOU ARE WELCOME.

I'm a small amount confused though. Basically what I'm trying to do is get the pistons at TDC without the timing mark being correct?
THE METHOD I PROPOSE USING ALLOWS YOU TO MOVE THE CRANK WITH NO T/BELT ON MINIMIZING THE RISK OF BENDING VALVES.

Then im putting the cams at 180 degees from TDC and putting the blet on??
VERIFY THE 2 INNER PISTONS ARE NOT AT TDC & SET THE CAMS ON THEIR MARKS AS CLOSE AS POSSIBLE -DOWELS UP.

I put the cams at exactly 180 degees from TDC and took the spark plugs out.
YOU ARE LOSING ME HERE... WTF? - DO YOU MEAN DOWELS DOWN?

When I looked into the chamber I can see that the outer pistons are almost at TDC and the middle pistons are almost all the way down.
GOOD - SET THE CAMS AT THEIR MARKS DOWELS UP & THEN PUT #1 AT TDC - BUT DO NOT LET THE INNER PISTONS GO TO TDC & BEND VALVES!!!!!!!!!!!!!!!

I'm assuming that when the cams are 180 off that the valves are closed and that the motor is at TDC again correct? IF YOU MEAN WHEN THE DOWELS ARE DOWN - WHEN DOWELS ARE DOWN #4 IS ON COMPRESSION STROKE & #1 IS ON EXHAUST STROKE.

 

[mark95turbo]

Yes, by 180 degrees from TDC I meant the dowels are down.

So basically if I have the outter pistons at TDC and the inner pistons not at TDC, I can move the cam gears to TDC with minimum valve\piston contact, and then all of my valves will be closed so I can then move the crank\oil pump to TDC and put the belt back on? Does the oil pump have to be rotated along with the crank? Thanks a TON Buck!

 

[BUCK]

I'M IN CAPS AGAIN FOR EXPEDIENCY...

Yes, by 180 degrees from TDC I meant the dowels are down.
OK.

So basically if I have the outter pistons at TDC and the inner pistons not at TDC, I can move the cam gears to TDC with minimum valve\piston contact,
LOWER THE HIGHER PISTONS HALF WAY DOWN - ALL 4 WILL BE MID STROKE THEN - NO WAY ANYTHING CAN HIT ANYTHING - THEN MOVE THE CAMS TO DOWEL UP - THEN BRING 1 & 4 TO TDC - DO NOT BRING 3 & 4 TO TDC.

and then all of my valves will be closed
ALL OF YOUR VALVES ARE NEVER CLOSED - NEVER!!! THAT'S WHY YOU HAVE TO BE THIS CAREFUL!

so I can then move the crank
PER THE ABOVE....

\oil pump to TDC
SET YOUR REAR BALANCE SHAFT PER THE VFAQ OF COURSE....

and put the belt back on?
SEE MY PREVIOUS ABOUT EXHAUST CAM BIAS...

Does the oil pump have to be rotated along with the crank?
NO - CRANK & CAMS COULD CARE LESS ABOUT OIL PUMP POSITION - BUT YOU MUST TIME REAR BALANCE SHAFT (WHICH YOU SHOULD BE SHITCANNING ANYWAY...) WITH OIL PUMP SPROCKET !

Thanks a TON Buck! NO PROBLEM

 

[mark95turbo]

Just an FYI for future reference for others trouble shooting. This worked like a charm! I just put 2 rods that were equal lenghts into one outter chamber and one inner chamber through the sparkplug holes. I then moved the crank sprocket so that the middle rod moved up and the outter rod moved down until they were parallel with eachother. Then I moved the cams so that the dowells were pointing straight up and then moved the crank to the TDC mark. I had 0 contact between the valves and the pistons. You are a lifesaver Buck!