Closing after surgery
#1
Closing after surgery
Today I finished installing timing chains , complete with guides and tensioners for both primary's and secondary's on my wife's 2000 XJ8. I as well as countless others I'm sure, relied on the extremely detailed and well illustrated procedure laid out in black onyx senior member from this site. A huge thank you for your willingness to format that for the benefit of us all.
I post today because of the apprehension I am feeling after installing the timing cover on my way to completing this job.
It's nessasary to install the secondary chains in such a manner that the exhaust sprocket and the intake sprocket are 1/2 tooth out of sync. I spent considerable time interpolating this arrangement but came away less than 100% sure.
I plan to rotate the crank via the crank pulley bolt prior to total assembly and cranking with the starter. Trying to avoid doing any damage if I didn't have the relationship of those sprockets right. Any thoughts?
I post today because of the apprehension I am feeling after installing the timing cover on my way to completing this job.
It's nessasary to install the secondary chains in such a manner that the exhaust sprocket and the intake sprocket are 1/2 tooth out of sync. I spent considerable time interpolating this arrangement but came away less than 100% sure.
I plan to rotate the crank via the crank pulley bolt prior to total assembly and cranking with the starter. Trying to avoid doing any damage if I didn't have the relationship of those sprockets right. Any thoughts?
#3
That was all as it was supposed to be. But to put new chains the sprockets need to be removed from the cams and new chains installed and it's at this point that the relationship of the exhaust and intake sprockets may have inadvertently changed.
#5
#7
I'm comfortable with how the whole process went, even using supplied shims to take the slack out of the drive side of the chains before tightening the sprocket bolts. It took some time to acquire all the nessasary tools and parts so I want to be as sure as I can be that I haven't overlooked anything.
Trending Topics
#8
Rotate the crank manually with a 24mm socket for at least 2 rotations. The reinstall the crankshaft locking tool on the flywheel. Then take one of your camshaft locking bars and it should slide over the cam flats on both sides. If it doesn't it is not timed correctly and I would reset the cams again. I had to redo mine once because after rotating the crank the bar didn't slide over the cam flats. It was only of a little but you want it set correctly so you have maximum performance.
#9
Rotate the crank manually with a 24mm socket for at least 2 rotations. The reinstall the crankshaft locking tool on the flywheel. Then take one of your camshaft locking bars and it should slide over the cam flats on both sides. If it doesn't it is not timed correctly and I would reset the cams again. I had to redo mine once because after rotating the crank the bar didn't slide over the cam flats. It was only of a little but you want it set correctly so you have maximum performance.
#10
I also saw that remark in the directions about having the sprockets 1/2 tooth off. I struggled with the meaning of that and also struggled regarding whether or not I accomplished it. I could not think of any logical reason for it as long as the timing was correct, but I still wanted to do the job "perfect" so I tried to line the sprockets up as directed.
In the end I never had a good feeling that I did indeed get them 1/2 tooth off, but like RobRoy said I just made darn sure the timing was right by rotating the engine. In my case I turned it about 10 times! It purred perfectly immediately upon start-up, and I drove it about 12,000 miles from that point until I sold the car, so all was well.
In the end I never had a good feeling that I did indeed get them 1/2 tooth off, but like RobRoy said I just made darn sure the timing was right by rotating the engine. In my case I turned it about 10 times! It purred perfectly immediately upon start-up, and I drove it about 12,000 miles from that point until I sold the car, so all was well.
#11
I also saw that remark in the directions about having the sprockets 1/2 tooth off. I struggled with the meaning of that and also struggled regarding whether or not I accomplished it. I could not think of any logical reason for it as long as the timing was correct, but I still wanted to do the job "perfect" so I tried to line the sprockets up as directed.
In the end I never had a good feeling that I did indeed get them 1/2 tooth off, but like RobRoy said I just made darn sure the timing was right by rotating the engine. In my case I turned it about 10 times! It purred perfectly immediately upon start-up, and I drove it about 12,000 miles from that point until I sold the car, so all was well.
In the end I never had a good feeling that I did indeed get them 1/2 tooth off, but like RobRoy said I just made darn sure the timing was right by rotating the engine. In my case I turned it about 10 times! It purred perfectly immediately upon start-up, and I drove it about 12,000 miles from that point until I sold the car, so all was well.
#12
The 1/2 tooth just refers to the gears on the crank. They can be positioned so that the teeth of both are the same, or by flipping one over, the tooth of one aligns with with the valley of the other. Does not matter which way If you then used the cam locking to set the flats.
#13
Timing an XJ8
Rotate the crank manually with a 24mm socket for at least 2 rotations. The reinstall the crankshaft locking tool on the flywheel. Then take one of your camshaft locking bars and it should slide over the cam flats on both sides. If it doesn't it is not timed correctly and I would reset the cams again. I had to redo mine once because after rotating the crank the bar didn't slide over the cam flats. It was only of a little but you want it set correctly so you have maximum performance.
Initially I kept the cam locking tool in place on the right bank while I lossened the cam sprocket bolts thinking the cams would align themselves but I didn't want to use the locking to gain that last little bit so I removed the CLT and that's when the exhaust cam seemed to turn out of alignment
#14
#15
I used vice grips CAREFULLY on the cam and tightened the holding tool while turning until it was aligned. If you have the gears still in place and tight you can probably use the allen bolts holding the cam gears on to turn them while you tighten the CLT.
Make sure you have the other side's CLT in place and tight so you keep the other cams in time while you correct the bad side.
Make sure you have the other side's CLT in place and tight so you keep the other cams in time while you correct the bad side.
#16
Day job
x
I used vice grips CAREFULLY on the cam and tightened the holding tool while turning until it was aligned. If you have the gears still in place and tight you can probably use the allen bolts holding the cam gears on to turn them while you tighten the CLT.
Make sure you have the other side's CLT in place and tight so you keep the other cams in time while you correct the bad side.
Make sure you have the other side's CLT in place and tight so you keep the other cams in time while you correct the bad side.
Mahalo for your thoughts.
#17
Must be missing something. Crank lock in place:check/Cam lock on both banks installed:check. But after tightening both sprockets and rotating the crank by hand a few times the right bank continues to come up out of sync. After several attempts the cam tensioning tool cracked at one of the pins. Couldn't have been more cheaply made.
The teeth on both crank sprockets are in phase with one another. Could that be the problem? I read that it didn't matter as long as the flats were aligned on both cams.
The teeth on both crank sprockets are in phase with one another. Could that be the problem? I read that it didn't matter as long as the flats were aligned on both cams.
#20