Quick question, when the crankshaft is on mark, does this indicate no pistons are at top of compression cycle, as in, if cams are installed and set up that none will be bent? I picked up one of those please help finish project deals for a friend, and am dealing with belt off, and I don't want to turn cams to appropriate marks unless it is safe to do so. Obviously, the cams are not set to top of cover and I don't want to rotate them unless I know it is safe with crankshaft on mark.
Thanks in advance.
camshaft alignment
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precopster
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When crank is on the mark Robert (on You Tube) shot a video that shows you can freely spin both exhaust and intake cams without hitting the pistons. That may have been on a 1998 motor.
On the 5 cylinder piston 1 is actually only about 1.5mm shy of top position so it's a close call.
On the 6 cylinder white block piston 1 is quite a way down and other cylinders are not near the top.
On the 5 cylinder piston 1 is actually only about 1.5mm shy of top position so it's a close call.
On the 6 cylinder white block piston 1 is quite a way down and other cylinders are not near the top.
Current cars VW Transporter 2.5TDI, 2010 XC90 D5 R Design
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SuperHerman
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If in doubt - regardless of the motor - pull the spark plugs and put a stick in each cylinder and use a flashlight to look for the piston top.
The point is I don't want to turn crank more than I have to not knowing where valves are open to avoid damage. Other wise I would check piston travel. These no tolerance motors are insane to think engineers would make such a stupid design, but of course, it is all about programmed failure to feed the stealerships with major repair when belt, pullery or tensioner go, never mind water pump freezing up like mine did.
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SuperHerman
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I understand, but I don't think you will bend a valve turning anything by hand if you do it slowly and stop at any sign of resistance.
Like I said, pull the plugs and use a flashlight to see where the piston is for each cylinder. Then put a stick in each cylinder to get a reference of where they are.
You can pull a picture of the cams off the internet for both sides and figure out where the valves should be when they are in "cam lock" positions.
You know that when the crank is set to the right mark (not top dead center) and the cams are set to "cam lock" you will have no contact. Also the engine should have a "safe" place for head removal and if I recall correctly this is at the crank mark - if you turn the crank to this spot you should be able to start fresh. Check VIDA. Just do a little research and don't force anything.
As Precopster stated: "On the 6 cylinder white block piston 1 is quite a way down and other cylinders are not near the top." My recollection of my old S80 with the 2.9 is consistent. I replaced the headgasket and had no issues. Just use the flashlight and stick technique to confirm and you should be fine. The more I think and recall I also wondered about top dead center and learned that top dead center was not the same as the crank mark.
Like I said, pull the plugs and use a flashlight to see where the piston is for each cylinder. Then put a stick in each cylinder to get a reference of where they are.
You can pull a picture of the cams off the internet for both sides and figure out where the valves should be when they are in "cam lock" positions.
You know that when the crank is set to the right mark (not top dead center) and the cams are set to "cam lock" you will have no contact. Also the engine should have a "safe" place for head removal and if I recall correctly this is at the crank mark - if you turn the crank to this spot you should be able to start fresh. Check VIDA. Just do a little research and don't force anything.
As Precopster stated: "On the 6 cylinder white block piston 1 is quite a way down and other cylinders are not near the top." My recollection of my old S80 with the 2.9 is consistent. I replaced the headgasket and had no issues. Just use the flashlight and stick technique to confirm and you should be fine. The more I think and recall I also wondered about top dead center and learned that top dead center was not the same as the crank mark.
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precopster
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You get this motor to marks by degrees. Turn crank slightly then turn cams slightly by hand by 10 degrees each time. If you hit a piston while turning the can back it off a smidgeon then continue to turn the crank by 5 degrees.
There is 2 turns of the crank for 1 turn of the cams. ie crank has 21 teeth on belt drive and cams have 42 teeth. Cams are larger and you will have more control if you do most of the turning with cams. So you will have more control and better feel if hitting occurs.
You will have to get through this by doing. Thinking it through won't work unless you do as Superhernan suggested and open spark plugs so you can poke a straw to touch pistons so you can get an idea of where they are. Most important thing is to get crank on mark first then spin cams to their respective positions.
If you want to do this in the safest possible way with no chance of hitting you will need to remove the top of the cam cover to release the valve springs and hen reseal the top cover.
There is 2 turns of the crank for 1 turn of the cams. ie crank has 21 teeth on belt drive and cams have 42 teeth. Cams are larger and you will have more control if you do most of the turning with cams. So you will have more control and better feel if hitting occurs.
You will have to get through this by doing. Thinking it through won't work unless you do as Superhernan suggested and open spark plugs so you can poke a straw to touch pistons so you can get an idea of where they are. Most important thing is to get crank on mark first then spin cams to their respective positions.
If you want to do this in the safest possible way with no chance of hitting you will need to remove the top of the cam cover to release the valve springs and hen reseal the top cover.
Current cars VW Transporter 2.5TDI, 2010 XC90 D5 R Design
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SuperHerman
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Precopster: Tell me where I am wrong. I am not saying you are wrong - just testing my understanding.
1) When the Crank is set to the crank mark and the heads are off it cannot be 180 degrees out of time as one rotation is 360 degrees.
2) Only when the heads are installed and the timing belt is also installed can the crank and valves be 180 degrees off.
3) On the 2.9 Volvo engine when crank is set and lock put in the starter and appropriately adjusted the crank should be set correctly. As you stated before, which is my recollection of the engine piston positions, none of the pistons can contact a valve regardless of where the valves sit in their rotation if the crank is at the set mark.
4) Locking the crank, via the starter hole, still has the crank lined up at the mark on the gear and oil pump.
5) If this is correct, and the timing belt is not installed, then one can rotate both cams 360 degrees without piston contact.
6) So the solution is to get the crank to the mark, (lock it via starter plug if wanted) then rotate the cams to get the cam lock tools installed. After this then properly manipulate the CCV and install the timing belt.
What if anything have I stated incorrectly? Looking at the instructions of changing a head gasket - this seems consistent.
1) When the Crank is set to the crank mark and the heads are off it cannot be 180 degrees out of time as one rotation is 360 degrees.
2) Only when the heads are installed and the timing belt is also installed can the crank and valves be 180 degrees off.
3) On the 2.9 Volvo engine when crank is set and lock put in the starter and appropriately adjusted the crank should be set correctly. As you stated before, which is my recollection of the engine piston positions, none of the pistons can contact a valve regardless of where the valves sit in their rotation if the crank is at the set mark.
4) Locking the crank, via the starter hole, still has the crank lined up at the mark on the gear and oil pump.
5) If this is correct, and the timing belt is not installed, then one can rotate both cams 360 degrees without piston contact.
6) So the solution is to get the crank to the mark, (lock it via starter plug if wanted) then rotate the cams to get the cam lock tools installed. After this then properly manipulate the CCV and install the timing belt.
What if anything have I stated incorrectly? Looking at the instructions of changing a head gasket - this seems consistent.
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precopster
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Sorry didn't know I contradicted anyone. I suggested he follow your advice if you read my thread carefully. 
. I totally support your method Superhernan. I thought I just worded it differently. There are more than a hundred posts on this very same topic here on MVS and so far haven't heard anyone give anybody bad advice. Putting belt on and hoping for the best would be bad advice.
. I totally support your method Superhernan. I thought I just worded it differently. There are more than a hundred posts on this very same topic here on MVS and so far haven't heard anyone give anybody bad advice. Putting belt on and hoping for the best would be bad advice.Current cars VW Transporter 2.5TDI, 2010 XC90 D5 R Design
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SuperHerman
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Mike: I didn't take your comments as a contradiction - in fact your comments reminded me how the 2.9 engine sits when at the crank marks.
I just was asking you to confirm the points to make sure I was not wrong. The way I figured is someone in the future would read it and hopefully be helped out. Because the timing on the 2.9 does not use a true TDC it gets confusing.
Enjoy the day.
I just was asking you to confirm the points to make sure I was not wrong. The way I figured is someone in the future would read it and hopefully be helped out. Because the timing on the 2.9 does not use a true TDC it gets confusing.
Enjoy the day.
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precopster
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Perhaps we can achieve more on a thread about a 2.9 motor as this one is for a 5 cylinder 2.5T.
I was scouring my photos today for a pic of my 2.9 960 at the crank mark with the head removed but couldn't find it. Piston 1 was definitely way down there.
I was scouring my photos today for a pic of my 2.9 960 at the crank mark with the head removed but couldn't find it. Piston 1 was definitely way down there.
Current cars VW Transporter 2.5TDI, 2010 XC90 D5 R Design
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