I'm trying to figure a way to time an engine where the Cams AND Crank were moved with the Timing Belt Removed.

2002 Montero Sport XLS 3.5

The basics I know are: Crank @ TDC and Cam sprockets lined up with their respective timing marks.
My approach is to assume all three are at some random rotation and none of the three are at timing marks.
(Is it possible to do this "without" removing the Valve Covers? Watching the piston rise + valves open and close is the obvious way to confirm TDC.)


Not sure if I should start by rotating the Crank to TDC or rotate the Cams/Sprockets to their timing marks.

IF Crank first...
1) Rotate Crank sprocket to TDC.
(If there is interference, how do I determine which Cam/valves to move out of the way so I can continue to rotate Crank to TDC?)

2) Rotate the Cams/Sprockets to align their timing marks.
(If there is interference, what would I do next?)

If Cams first... the same questions I guess.

I've pulled the plenum to replace plugs, valve covers etc so I'm familiar with process. I'd just prefer not to if I could. Time & another trip for parts etc.

All help, suggestions and jokes are welcome!!!
JC

 

You do not need to remove the valve covers. That will not give you any advantage. You have to rotate both camshafts and a crank shaft slowly and carefully and at about at the same time. You want to have the timing belt on and have everything move at once. If you feel resistance - stop and try to move one of the camshaft to see if you can remove the interference. Do not force anything.go forward a little, backward a little. Then continue until you get all three marks in the right place. It will take some patience. Make sure you have a good camshaft holder/turner. It will be frustrating, scarry and slow, but it is possible to do.

 

Thanks HunterD!

Question: When all three marks line up is that a guarantee the Crank is at True TDC and the Cams are synced as well?

I'm guessing it is, I'll know when I get there. Obviously the Crank can be at TDC "technically" at the beginning of the Intake and Power strokes. I don't recall which is "True".
It's been about 30 years since I've been here. Thanks again for the help.

 

If the timing marks alliagn, all your pustons and valves will be in the right places. The crankshaft does rotate twice for every rotation of the camshaft, but the camshaft "does not care" if timing is set on the first crankshaft rotation or the second. The pistons will be in exat same position. The trick will be to get past the spots where interference does start to occur by smartly analyzing which way to move the crankshaft and camshafts to remove this and to get everything to the right timing marks.