2002 V70 Timing from scratch , adjusting VVT Topic is solved

SCP74 · Post by **SCP74** » 08 May 2020, 14:49

You all have been great so far, cheers to the Volvo community!
My issue is that I've taken the belt off my 2002 v70 WITHOUT setting time on all three marks( I was turning counter clockwise instead and ended up with the cam marks up at like 11:58 o'clock, and the crank was way off. Thought all of this could be corrected before tensioning belt.)
So, before being corrected of my folly, I was turning the bolts on WP to check torque and ended up going too far with one. Whilst getting help about that bolt hole, my mechanic asked if I'd reloaded the VVTs. At this point, I'm looking at resetting the time on the cams, locking up the cams from rear and performing adjustment of the VVT unit on the front, and remarking my time on the gears. Taking out the locking tool, then setting the tensioner, and following through with the belt assembling.

Please help me out with the part about putting the cams in their factory spot, before installing lock tool to adjust the VVT(INDEX). As I have heard, they can be moved with a flat head screwdriver to where the line where head and block is meeting, in line with the rear of cam shaft horizontally. Is that right?

And is the step where I index the VVT cam positively necessary?

Lastly, by turning the crank counterclockwise 2 revolutions would any contact that's detrimental have happened?

That in advance for your input!

Post by **abscate** » 09 May 2020, 03:09

The first step is to get the crank back to the timing clearance mark. Start moving I towards the mark, when you feel tension, stop, move up the cams and move both until the crank moves again

It helps to have all the spark plugs out so you can differentiate compression resistance from valve contact

Work the crank to the mark and leave it there. Now you can move the cams with impunity as they will never touch the pistons.

If you didn’t loosen the big bolt on the VVTS you don’t need to reindex the cams

Do you have one or two VVTS?.

Remember that the timing on a VVT car is set by passing the cam marks then returning to them counterclockwise wise, otherwise it will code.

ignatz · Post by **ignatz** » 09 May 2020, 07:14

Lastly, by turning the crank counterclockwise 2 revolutions would any contact that's detrimental have happened?
Yes, if the camshafts did not move...and the crankshaft rotated two revolutions.......valves are bent. Maybe only slightly, but damage is done.
There's a guy on Youtube....Robert DIY, who does Volvo repairs. His one video called, What happened if your vehicle's timing belt broke or came loose on an interference engine.
Watch the video from start to finish, and try to remember how "easy or hard" it was to rotate the engine two times.
Remember, if you stand in front of a door that opens towards you, and someone opens the door and feels resistance and stops...your OK.
If they return with Uncle Brutus and he kicks the door in...your the bent valve.
After you get it back together, do a compression test, or leak down test, to confirm if its worth going forward.
I like the part in the video where he says, Stop wishing, hoping and praying. At some point, you should have a good idea if you rotated the engine into an open valve.

SCP74 · Post by **SCP74** » 09 May 2020, 20:49

I talked to someone reputable and they said find the crank mark, and proceed to turn the cams to their position. I did use the method you used. After belt was off I rotated crank clockwise to line up at his mark. Had to go back and forth a little, just like with the cams, but I got everything in line.
I did begin removing the stuff covering the cams from the back. I popped the intake csp, and removed the sensor on exhaust. I was able to verify the factory alignment by looking at the engine seam and it's position to the cams horizontally. But the trigger sensor now, when releasing or being tightened, is moving the shaft. Should I wait until putting on the belt before tightening the trigger wheel?

Post by **abscate** » 10 May 2020, 04:29

The torque on the sensor is pretty low,like 12 Nm, verified.

You can get that by just grabbing onto the sprocket as a counter hold. This will clock the sprocket clockwise again, so you need to go back and reset the cam mark, turning the sprocket at least 1/2 a turn counterclockwise,again, same as you do with the timing belt.

However, if you have not removed the VVT hubs there is no reason to be working at the rear of the cams other than seal replacement.

SCP74 · Post by **SCP74** » 10 May 2020, 09:10

The belt was on when I turned the crank counter clockwise, I don't know if I made that clear. And the turning was done with a small wrench and just my hand strength. And it
Was more like one and a half turns.

So about finding the mark on the crank, so can I find it just by lining up the marks, or must I follow the method above, because I'm turning pretty hard on these cam sprockets and it feels like they slip into a free mode after a certain point and then it gets difficult to turn them again. Again I'm only struggling to line up the exhaust cam because it is a VVT unit and the intake I set pretty easily because it was only off by a couple since I removed the belt.

SCP74 · Post by **SCP74** » 10 May 2020, 21:31

After trying to tighten the trigger wheel while holding the cam sprocket, it was too much tension to tighten past a few foot pounds without the cam spinning.
Question: Is the trigger wheel torqued enough to perform with the sensor over it, as I can see it moving with the cam, or should I remove it, get the cam in the mark, then Install the belt , and torque to the spec, having the help of the belt to share the load?

On the crank issue, do I need to align it in a certain manner, or can it be aligned by going clockwise from where it was, then further adjusting it going past the mark, and coming back and aligning it fully? I mean is it sooo critical to land ON the mark going clockwise, or can you pass it and correct it? The VIDA instructions , using the crank shaft adjustment tool, have you going counterclockwise, then forward with it. I know they are for use with the tool, but going both ways to certain degree, with the crank at this point would seem safe.

Very concerned about the pistons and possibly valves, as the VIDA instructions are so strict about the movements in their guide, and deviation from them is pointed out as possibly causing harm to the engine. Again, to be fair, their instructions are for installing the vvt and adjustment. Hope to have a good understanding of the system by the end of this saga. Been up on stands over a week.
Thanks for the guidance.

Post by **abscate** » 11 May 2020, 04:42

It won’t matter from a contact point of view if you set the marks going clockwise or counterclockwise.

The sprocket ends up in the same position, the cam is retarded two teeth when you set the marks going counterclockwise. No valves will hit the pistons either way.

The correct way to set it up is from the counterclockwise turning crank. When turning ccw, go slowly and let the mechanical tensioner relax back to the center position if it goes full over the right. You only have to go 1/2 crank turn past and then back.

I wrote up an epic battle with this from a few days ago with my 99 exhaust VVT under thread title P0014. These cars need to be pretty close to not code.

SCP74 · Post by **SCP74** » 11 May 2020, 10:33

The belt is off, that is why I m starting over. I took off the belt with marks not in line. Simply put.

SCP74 · Post by **SCP74** » 11 May 2020, 10:36

What about tightening trigger wheel? I'm stuck waiting to know whether I should try and torque it later ,after putting on the belt.