2004 C-70 HPT T-belt TENSIONER adjustment

[Dirtbag454]

Hello:
Just finished a t-belt, water pump, idler and TENSIONER replacement on my honey's 2004 C-70, and I fear that I may have not adjusted the TENSIONER correctly. (I'll stop with the all-caps on tensioner...just wanted to highlight that this is the point of this post.)

I have seen several posts that refer to the adjustment procedure on the temp sensing belt tensioner, and they talk about starting in the "2 o'clock position" or the "7 o'clock position" and moving the eccentric counter-clockwise until the indicator rests in the proper location for the current engine temperature. I understand the indicator position. What I don't understand is the starting position, and which engine it is applicable to. I also think I may have screwed up because I moved the eccentric clockwise to get the indicator in the correct position. I'm beginning to see that it can be moved in either direction (clockwise/counter-clockwise) and eventually that indicator will wind up where it is supposed to be, but is the belt tensioned correctly if it was rotated in the wrong direction? Could someone please shed some light on this? I was crowing about fixing her car, and now I am not so sure I want to let her drive it as I may have to pull the covers off and re-tension that belt, lest it jump time and cause all sorts of other problems.
I have searched this forum for an adjustment procedure specific to the 2.3 HPT engine in my wife's car, but the closest I have come is for an S-60, and I believe it was a non-turbo. In any event, the vvt pulley was on the forward (intake) cam, and my vvt pulley is on the rear (exhaust) cam. This might make a difference...I don't know because I can't find anything specific to this engine. I may not even be posting in the correct forum, as this one is for up to 2000 model year for this particular car. Since I could find no other forum for the ragtop, here is where I am.
here's a shot of two similar tensioners. Mine is on the left.

The same post I snaked that photo from had a video of the 2003 S-60 (non turbo) which clearly showed the tensioner being adjusted counter-clockwise, AND a Volvo technical bulletin which had a drawing of the adjuster, and gave printed instructions to move the eccentric CLOCKWISE. Perhaps you can see why I am confused. Any and all help will be greatly appreciated.
Dave
Oh crap. just previewed the post and the photo is too big. I got it from a thread on this forum too!

[Sardine]

starting in the "2 o'clock position" or the "7 o'clock position" and moving the eccentric counter-clockwise until the indicator rests in the proper location for the current engine temperature

I just did a 2004 V70 last week and like you, I was confused by the tensioner.
I used the FCP youtube video to set the tensioner. This is what it says for the tensioner on the left:
1) Start at 11 O'clock.
2) Turn the eccentric counter clockwise until the indicator exits the window to the right. The eccentric should be about 6 O'clock at this point.
3) Turn the eccentric clockwise until the indicator re-enters the windows from the right and arrives at the position for the correct temperature. The eccentric should be about 7 O'clock at this point.
The good doctor at FCP also briefly says that for the new tensioner, i.e. the one on the right in your picture, the starting position for step 1) should be at 2 O'clock. Since my tensioner is the new one, I'm very interested in this step but he did not elaborated. Since the two tensioners are geometrically identical, I just could not see why the starting positions should be different.
In the end, I just started at the 11 O'clock and the tensioner seemed to behave the way it should when I pushed on the belt. Actually, the starting position did not seem to matter. The tensioner seems to respond the same way when the belt is pushed, no matter where I started the eccentric.
My car has now done about 50 km and nothing bad has happened yet. The tensioner indicator stays in the same position that I set. The indicator still moves to the right when I push the belt. From what I read, these are the only important points about the tensioner setting. I would get back in and re-adjust the tensioner if somebody could give me a reason why I should.
By the way, why do you think the cam shaft vvt or the turbo/non-turbo is relevant to the tensioner?

[Dirtbag454]

hi Sardine, thanks for your reply. to go to the end first, the vvt pulley position seems to change from engine to engine, and from model to model. My 2004 C-70 has the vvt pulley on the exhaust cam (rear), but the 2003 S-60 (same basic motor?) has it on the intake cam. The S-60 is NA, my engine is turbo'd. Why there would be a difference is beyond me, but there must be a reason. there is a video on this forum that shows the replacement procedure and goes into the tensioning process, and it is the same as your description, but a little farther up the same thread there's a Volvo service bulletin (think I mentioned it) that describes the opposite (clockwise start) procedure as you outline. The tensioner is the same, the engines are both 5 cyl, the difference is the vvt pulley position and the Naturally aspirated/turbocharged. I still cannot fathom why the procedure would need to be different on ANY motor that used that tensioner on that 5 cylinder platform. What in the heck do those Volvo engineers do all day long?

https://www.youtube.com/watch?feature=player_embedded&v=IK_zH8g8Fow

[Dirtbag454]

BTW, Sardine, I'm going to go out and do the 11 to 7 counterclockwise procedure, just to be safe. (I'm beginning to hate Volvo) Also, I have had the similar experience on a 2000 S-80. They are not fun to work on. Way too complicated.

[Sardine]

While you are at it, make sure you turn the crank a few times to make sure that the indicator does not settle down in a different position from the one you set.The indicator should also move to the right when you push on the belt.
As far as the eccentric is concerned, I read somewhere that the indicator HAS TO move into the windows from the right (i.e. counter-clockwise) while the eccentric moves clockwise. Once the indicator is in the windows, you can move the eccentric a little bit clockwise or counter-clockwise to set the indicator position correctly.
I have now read the Vida instructions and it does say that "Ensure that the Allen hole on the eccentric is at 10 O'clock" before the belt is installed. For you, with the old tensioner, this is the right procedure. For me, with the new tensioner, I still don't know what I should do.

[jimmy57]

The CVVT on turbos aids in cold start emissions, effectively eliminates the need for the secondary air pump that was used in the past during the first minute of cold running.
On non-turbo engines the CVVT on intake stills aids with emissions but it has a great impact on better torque at low revs while also allowing higher HP at high revs.

The clock positioning of eccentric allen wrench port is a guide, not an absolute. The indicator that moves as you rotate the tensioner with allen wrench is the absolute. The purpose of going to higher than range tension and then adjusting back to the correct tension is to assure the belt gets tensioned all the way around. There could be enough drag of cams that stop the belt from being tensioned from intake gear back down to crank gear at the light tension the belt runs at. If you swing it to a higher tension you'll rotate the cam, if needed, and the belt will be tight throughout.

[oragex]

It looks scary at first, but actually it's pretty intuitive. It's all about adjusting the needle at the center position. Give it a try several times to understant how it works. Remember, every single time you release the tensioner bolt, you need to redo the complete tensioner procedure from the very start. The needle has to pass the 'center' position so you can adjust it at the center by slightly releasing it. What's important is to set the needle at the center at room temperature (cold engine). Then run the engine a few seconds to check the needle is still at center. Don't install the lower belt cover right away, leave it off and recheck the needle a few days later.

Small trick: in order to have the needle stay at center while finally tightening the tensioner bolt, have the tensioner bolt a bit tight before adjusting the needle (just enough tight so you can see the needle moving without much effort).

[Dirtbag454]

jimmy57 and oragex, thanks for your replies. I was careful to pass the indicator post past the right goalpost, then move it back into position (center, cold engine, temp 68). I have noted that the post will move to the right no matter which direction the eccentric is moved (cw or ccw), and the post moves to the right when the belt is pressed. My concern is why Volvo instructs cw in one application and ccw in another. The predominance of evidence suggests that a ccw eccentric rotation is the favored method, so I have adopted that. We are driving the car to an event tonight to get a first look at the new XC-90, and with any luck, it will uneventfully complete the round trip (about 80 miles).
Jimmy, thanks also for your shedding light on the CVVT intake or exhaust placement. I first encountered that system on our S-80. The sprocket didn't "unload" as expected (rotate crank about 1/4 turn ccw, then back to marks) and the sprocket jumped about 2 teeth when I slipped the belt off. I thought, "oh crap, now what am I gonna do?" Thought I'd need to get the cam lock tools and do a whole bunch of extra work because I hadn't unloaded the spring. Then I thought about it,and realized that the cam had not moved, just the spring loaded sprocket. I pushed it back into position when I put the new belt on and it ran flawlessly, until the trans went away. But that's another story...

[oragex]

I have the tensioner on the left side on your picture here above, it starts with the eccentric at about 10, moves ccw towards 7 to bring the indicator at about 1 o'clock (it will stop there and won't move any further) then moved a bit cw to bring the indicator back to the center between the two metal tabs. Only after the indicator goes past 1 o'clock it will move back to center (that is ccw) when the eccentric is moved cw.

I think there were two types of tensioners depending on the years

All this with the center bolt a little bit tighten so the indicator doesn't move by itself when it's time to fully tighten the bolt (which by the way is not tighten too much, 15 ft.-lb.). Once tightened, I would turn the belt a couple of times to see if the indicator remains in the middle. If the indicator is not at center at the end, the adjusting sequence should be restarted with the eccentric from 10 o'clock.

http://www.underhoodservice.com/volvo-t ... tensioner/

[Sardine]

the belt must be turned two complete turns.

I've never heard that and I didn't do it. I only dared turn the crank after making sure every thing looks right, including the tensioner.
The Vida document I read makes no mention of turning the crank before adjusting the tensioner:
https://www.matthewsvolvosite.com/forums ... =1&t=45937
Click on the link "04 XC70 Timing Components.pdf" in the post by Ozark Lee to get the Vida doc.