camshaft alignment, did I do it right

bobsnow100 · Post by **bobsnow100** » 26 Sep 2006, 08:00

Hello
I have a 1994 850 non turbo wagon.
I had a water pump fail which caused bent valves,etc, in my cylinder head I bought a used head which only needed 2 valves. I took all the valves out , cleaned and lapped them all ,sprayed carb. cleaner into the intake and exhaust ports to make sure there was no leakage from the ports through to the valve seats, installed new valve seals. Got everything reinstalled.
Here is my problem ,the car starts right up seems like the timing is off . If it is idling and I rev it , it is fine but when under load(driving) it feels like it is misfiring or the timing is off slow to pick up speed,real sluggish, I know you can't adjust the timing but I think my camshafts may be off a little.
I am thinking that when I adjusted them that maybe I did something wrong
Fisrt I had the engine at TDC with the mark on crankshaft pulley (v mark on gear edge,boy is that a small mark), Locked the rear of the camshafts with a tool I had made which kept them from moving and parllel.The front marks on the camshaft gears appeared to line up correctly,(exhaust at about 2 o'clock position and the intake about 10 o'clock position)
Had the camshaft gear bolts loose and one removed in each. Placed the timing belt around everything and kept it tight on the right side of the intake cam gear to the crankshaft gear, loosened the tensioner at this point and hit the belt in between the top gears which tightend the belt 100%. Next I torqued the bolts on the camshaft gears before I remove the camshaft alignment tool. Removed the rear camshaft alignment tool and put everything back together.
Car runs rough, Did I do this right or did I miss something
Thanks for reading this long story

dannyboy · Post by **dannyboy** » 26 Sep 2006, 10:57

seems like you did it allright.
Have you checked your codes?

Post by **Ozark Lee** » 26 Sep 2006, 21:32

Bob,

My guess is that you are off on your timing belt as you sorta suspected. Pull the cover again and crank your crankshaft back #1 TDC. Recheck the (impossible to see) timing marks on your camshaft pulleys and where they line up with the v grooves. I'm betting that you are off by one tooth and it's likely on the intake side. The distributor is driven off of the intake camshaft which, if its off, messes with the timing.

...Lee

bobsnow100 · Post by **bobsnow100** » 27 Sep 2006, 06:58

I checked the engine codes and there were none
I did check and re do everything again.
Put engine at TDC with the little v mark (for everyones info:actually if you look on the backside of the crankshaft pulley, there is a bigger mark)
Took the distributor out, camshaft position sensor out , locked the rears of the cams in place
loosened the cam gears
Took the tensioner out to re set it and re installed it, and then released the tensioner
hit the belt on top to align the cam gears and tighened them
checked that the engine crankshaft was still on mark
took off the cam locking tool
handcranked the motor over a couple of revolutions and rechecked the marks and everything looked right.
Idles ok and starts up instantly, but when you drive it it is real sluggish and shakes . once your up to high way speed it seems smooth until you accelerate. It does seem like the timing is off.
Well if anyone else has any ideas please let me know

Post by **Ozark Lee** » 27 Sep 2006, 07:11

Since you double checked the timing belt alignment I guess the next thing to check is compression. If the compression checks out I would start looking at the intake manifold to make sure it isn't leaking air. How were the pistons after they hit the valves?

...Lee

dannyboy · Post by **dannyboy** » 27 Sep 2006, 07:44

bobsnow100:

I assume that you checked both injection and ignition codes (sockets 2 and 6 I think) or go to this http://www.troublecodes.net/Volvo/ to make sure.
As it looks like the engine is running smooth on idle and on leveled high revs, so that in fact it does only "hesitate" when accelerating, it make me think more of an ignition "advance" (I am not sure if its the right wording) problem.
Initial timing setting is not the only issue as when accelerating the EMU will (or should)automatically adjust the timing forward (earlier). Have you checked the spark plugs? What kind of colour are they? Are the gaps between electrodes OK? You need a particularly strong and straight blue spark when accelerating as the gas mixture is becoming more rich. Normaly you do not experience these problems with electronic ignition systems unless you have poor condition plugs, high voltage leaks, or wrong gaps.

bobsnow100 · Post by **bobsnow100** » 27 Sep 2006, 08:02

Yes ,I did check codes in both 2&6 in A . got 1-1-1 in both,
Plugs are gapped and were the same ones in it when the water pump went, I actually put on my inductive timing light on each spark plug wire as the engine was running and had the strobe flash for each one. The color on the sparkplugs did look the engine was running a little rich, The car had been out of commission for the last couple of months so I'm wondering if something got messed up for sitting a while.
I am going to do a compression test next but I don't think that is a problem
I'm baffled

dannyboy · Post by **dannyboy** » 27 Sep 2006, 08:23

bobsnow100:

Well at this stage and knowing that you are using the same plugs, I would definitely try with brand new ones.
The plugs that were on when the valves went away might have been damaged (you might not be able to see it). Eventhough there is high voltage on your wires and the plugs look good it does not mean they operate well under high pressure. Isolators of one or several plugs might be cracked leading to high voltage leak(s).
I have had similar symptoms (?) on mine but due to the fact I forgot to change the plugs on time (they had more than 45.000 Kms!)
Changed the plugs and everything went back to normal.
I was assuming that having re-built the head you would have changed the plugs.
I suggest you try that, it is not an expensive test and it wouldn't do any harm.

bobsnow100 · Post by **bobsnow100** » 27 Sep 2006, 08:33

Good idea, I'll change em out tonight, Thanks for your thoughts.

bobsnow100 · Post by **bobsnow100** » 28 Sep 2006, 09:29

Well the plugs didn't do it, I'll try a compression test next. I did take each plug wire off one at a time,started then engine and each time the engine ran worse so I know all cylinders are firing
If all else fails,I have a 1995 850 which I'll compare my alignment marks and cam marks to it .
The top of the pistons were fine when I had the head off