Cam marks, TB/WP job
#1
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Cam marks, TB/WP job
Ok, I'm getting started on this TP/WP job on my 94 GTS and have a question.
I've rotated the engine a bunch of times now, using Wally's writeup, John Pirtle's writeup and the WSM, pages 15-101 forward for 32 valve engines.
As I rotate the engine to 45 degrees, the cam gear marks (red paint on front, grove on the back) align with the groove on the cam plate, just like the pictures.
However, when I rotate to 0/T (zero degrees TDC), the passenger side (
US model) cam gear marks are not quite aligned with the mark on the cam plate. It's off by about 1/2 to 1 tooth of the cam gear.
Is this normal? If not, what to do next?
Thanks
I've rotated the engine a bunch of times now, using Wally's writeup, John Pirtle's writeup and the WSM, pages 15-101 forward for 32 valve engines.
As I rotate the engine to 45 degrees, the cam gear marks (red paint on front, grove on the back) align with the groove on the cam plate, just like the pictures.
However, when I rotate to 0/T (zero degrees TDC), the passenger side (
US model) cam gear marks are not quite aligned with the mark on the cam plate. It's off by about 1/2 to 1 tooth of the cam gear.
Is this normal? If not, what to do next?
Thanks
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It's common for the marks not to line up exactly. Just be sure you make note of which way it's off so that you put it back the same way when you replace the belt if you do the job at TDC. .
#3
Three Wheelin'
It's normal. Your cam sprockets have worn and belt has stretched/seated in so there will be some difference. Many variables all culminate to cause the marks to be off a little. The important thing is how the cams are timed and that's different than the marks lining up. The marks show the relationship of the cam sprockets. That's all.
Originally Posted by wds928
Ok, I'm getting started on this TP/WP job on my 94 GTS and have a question.
I've rotated the engine a bunch of times now, using Wally's writeup, John Pirtle's writeup and the WSM, pages 15-101 forward for 32 valve engines.
As I rotate the engine to 45 degrees, the cam gear marks (red paint on front, grove on the back) align with the groove on the cam plate, just like the pictures.
However, when I rotate to 0/T (zero degrees TDC), the passenger side (
US model) cam gear marks are not quite aligned with the mark on the cam plate. It's off by about 1/2 to 1 tooth of the cam gear.
Is this normal? If not, what to do next?
Thanks
I've rotated the engine a bunch of times now, using Wally's writeup, John Pirtle's writeup and the WSM, pages 15-101 forward for 32 valve engines.
As I rotate the engine to 45 degrees, the cam gear marks (red paint on front, grove on the back) align with the groove on the cam plate, just like the pictures.
However, when I rotate to 0/T (zero degrees TDC), the passenger side (
US model) cam gear marks are not quite aligned with the mark on the cam plate. It's off by about 1/2 to 1 tooth of the cam gear.
Is this normal? If not, what to do next?
Thanks
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Thanks guys. Makes me feel better about this project. Got the big bolt off, removed the pullys, but the damper seems to not want to come off tonight. I'll try again tomorrow evening after work.
#5
Three Wheelin'
Heat the hub a bit with a propane torch and try to pull straight off.
Originally Posted by wds928
Thanks guys. Makes me feel better about this project. Got the big bolt off, removed the pullys, but the damper seems to not want to come off tonight. I'll try again tomorrow evening after work.
#6
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Originally Posted by Louie928
Heat the hub a bit with a propane torch and try to pull straight off.
Be real carefull with the torch when you do this. The damper works by having a section bolted the the crank, and a 'floating' section bonded to the center section with a layer of urethane. That urethane layer is potentially damaged by excessive heat.
I was looking hard at the damper when we had our TB/WP celebration here a couple weekends ago. It looks like there's a flange on the front face of tthe inner section that goes up in front of the outer section. You can't see the urethane layer from the front, but it's easily visible from the back. If my suspicion is true, it would be OK to use a puller to apply gentle tension on the outer rim without worrying about damage to the flexible urethane layer in between the sections. We used a puller this way on one of the cars, thanks to a healthy layer of corrosion on the snout of the crank. After the balancer was removed, I used some fine emery strips to clean the crank up before we put the gears/washers/balancer/pulleys back on with a little never-seeze. Anyway, look at your balance to see if the urethane layer is shielded/supported by a flange off of the inner section before you get the big puller out.
#7
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Originally Posted by wds928
Thanks guys. Makes me feel better about this project. Got the big bolt off, removed the pullys, but the damper seems to not want to come off tonight. I'll try again tomorrow evening after work.
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#9
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Hi Bill,
I just did mine and the damper was a royal b@#$%@ch at first. I tapped it with a hammer as well as other things. Well when I grabbed it with the fingers of both hands on opposing sides with both thumbs in the middle and pulled, it slipped right off. I was stunned it was so easy.
Good luck
Frank Barnhill
79 Euro 39k miles
I just did mine and the damper was a royal b@#$%@ch at first. I tapped it with a hammer as well as other things. Well when I grabbed it with the fingers of both hands on opposing sides with both thumbs in the middle and pulled, it slipped right off. I was stunned it was so easy.
Good luck
Frank Barnhill
79 Euro 39k miles
#10
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On my '85, I tapped for an hour and got nowwhere, lots of penetrating oil, could feel the slightest wobble, but no joy on movement. You can try gentle prying, but I would do directly to 3 prong puller, snug up the center bolt, quarter turn, rotate the puller, snug and quarter turn, rotate the puller some more, just get it started; once it starts to move it will slide right off.
#12
Team Owner
Hi since your doing the TB it might be a good idea to see if the cam bolts are tight on the pulleys , To do this put the engine at the 45 deg mark first, then remove the timing belt, then the distributor rotors and install 3 little screws that the rotor screws came out of, this will hold the cams in position on the cam pulleys, get the big wrench 32mm I believe, and hold the nut on the end of the cam pulley and torque the 17mm cam bolt to spec. 47 ft/lb . If your going to be replacing the cam pulleys then you will also have to open the cam covers and retime the cams to the gears/engine TDC
#13
Team Owner
Ah, a few more things, make sure that all of the pulleys are in good condition if the belt has been run for any time in an over tensioned condition then there is a good chance that all of the pulleys will be damaged. On the cam pulleys look for even wear and that the belt tooth lining is not worn away, on the oil pump pulley look for the same condition and also see if the oil pump pulley is made of aluminum or steel, you want a steel pulley on the oil pump, and last look at the cam drive pulley on the crankshaft get a straight edge and put it on the teeth see if they are not worn down in the middle, if all look good then you can reuse the pulleys also check the timing belt tensioner and the waterpump unless your replacing the WP. Now, if the cam pulley bolts are not tight then there is a very good chance that the cams have lost their time to their respective pulley, if this has happened then the keyway in the camshaft that the cam securing hub slides onto might be damaged.
If all is tight then I would go ahead and put the new belt on and see where things line up . It is a good idea to mark the pulleys at the 45 mark so the belt can be installed in this position the reason for doing this at 45 is so there will be a lot less preload turning resistance on the cams ,and there is no chance that the valves will hit the tops of the pistons. Once the belt has been installed adjust the tensioner to take out the slack on the belt, then turn the engine in the direction of rotation, NEVER turn it backwards as there is a chance that you will damage the timing belt tensioner, turn the engine to TDC that will be 2 rotations see if your timing marks line up at the grooves on the backs of the respective cam pulleys and the the engine at TDC, if this is good , apply the belt tensioning tool and tighten the belt to 5.0 +.3 -0. Turn the engine a few more times and recheck the tension also watch for the belt run and see where things are lining up. If all is good then remove the plugs on the tensioner , carfully with a squirt can fill the tensioner with 90 weight oil. The fill hole is the one that is lower and closest to the passenger side, the bleeder hole is the top hole or closest to the crank shaft, ONLY put oil into the fill hole and make sure the bleeder screw is fully removed from the tensioner, otherwise you will possibly blow out you belt tensioner
If all is tight then I would go ahead and put the new belt on and see where things line up . It is a good idea to mark the pulleys at the 45 mark so the belt can be installed in this position the reason for doing this at 45 is so there will be a lot less preload turning resistance on the cams ,and there is no chance that the valves will hit the tops of the pistons. Once the belt has been installed adjust the tensioner to take out the slack on the belt, then turn the engine in the direction of rotation, NEVER turn it backwards as there is a chance that you will damage the timing belt tensioner, turn the engine to TDC that will be 2 rotations see if your timing marks line up at the grooves on the backs of the respective cam pulleys and the the engine at TDC, if this is good , apply the belt tensioning tool and tighten the belt to 5.0 +.3 -0. Turn the engine a few more times and recheck the tension also watch for the belt run and see where things are lining up. If all is good then remove the plugs on the tensioner , carfully with a squirt can fill the tensioner with 90 weight oil. The fill hole is the one that is lower and closest to the passenger side, the bleeder hole is the top hole or closest to the crank shaft, ONLY put oil into the fill hole and make sure the bleeder screw is fully removed from the tensioner, otherwise you will possibly blow out you belt tensioner
#14
Burning Brakes
This is a great thread that I am using to prepare for my upcoming TB/WP "party."
re: "NEVER turn it backwards" - When standing in front of the car, facing the engine, clockwise is forward, right?
re: "NEVER turn it backwards" - When standing in front of the car, facing the engine, clockwise is forward, right?
#15
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Right.
Originally Posted by LaughaC
This is a great thread that I am using to prepare for my upcoming TB/WP "party."
re: "NEVER turn it backwards" - When standing in front of the car, facing the engine, clockwise is forward, right?
re: "NEVER turn it backwards" - When standing in front of the car, facing the engine, clockwise is forward, right?