Well thanks guys. I thought the purpose of locking the cams was so you could get the belt back on exactly how the old one was in place. But evidently , from what everyone is saying, it's very easy to just use the timing marks and do it that way
I'm looking forward to doing this on Thursday or Friday when my gates belt/pump/pulley arrive from Rock Auto.
It is pretty straightforward to line them up. LIne up the DS cam as close to dead center between the dots as you can...for the PS cam if you can, bias the mark more toward the right (inboard side), when you release the tensioner, it should pull it in pretty close to dead center.
Also, to keep things in place while threading the new belt on, after I got the belt on the crank sprocket, I stuffed a rag between the timing case and the belt to hold it in place. Same thing after I got it on the DS cam. With the rags holding it in place, it makes it easy to finish threading it around the WP and the PS cam and tensioner pulley. Just remember to pull the rags out.....
I have done it both ways. 2 with using the TFC cam locks (long bolt through sockets) and 1 without. I will now do them without locking the cams although I would not go as far as saying it is harmless!! My finger begs to differ. Got caught between the belt and pulley during a "snap roll"!~ OUCH!
I also will use the method of installing the hydraulic tensioner by leaving it extended and alternating tightening each bolt slowly as the tension applies pressure on the Idler bracket. IIRC this method required advancing the drivers side cam 1 tooth to the right. And it is then drawn back as the tensioner is installed.
SO the cam sprockets snap back violently enough to hurt you if your fingers are near them? If thats the case I might want to lock them..... LOL.... I thought you had to pull on the belt to keep tension on it when installing it around each pulley..... will this tension cause them to snap back?
The cams will stay in position (properly aligned between the dots), in general. I've changed my TB twice, never had a cam flip around on me, but yes, there is a good bit of tension on them.
Only if you end up turning them beyond the alignment marks should you have to worry about it breaking loose on you. But the only time you'd be doing that would be to possibly make an adjustment to the TB fitment, in which case I definitely recommend using a breaker-bar and appropriate socket. Keep a firm grip and you'll be fine. Your leverage on the breaker bar will easily overcome the tension of the valve springs.
My first TB/WP swap was scary as all get-out, had never done any kind of work on an engine like that. I ended up one tooth off on the belt, didn't really notice until a day or two later and it ran rough at idle. Had to tear it all back apart and re-install the belt. Lesson learned - do NOT skip the step where you rotate the crank around a few times to verify that all the dots line up properly after a full rotation.
I thought you had to pull on the belt to keep tension on it when installing it around each pulley..... will this tension cause them to snap back?
If the cam sprockets are in the right position as you begin the install the belt, you really should not have a problem. The teeth & grooves on the belt & sprockets sort of keep everything in place as you move along. If you use the rag to keep it in place on the crank sprocket when you start, that will keep the teeth & grooves meshed, and the belt won't slip. Then you keep tension on it as you thread it around the DS cam sprocket. The belt doesn't stretch, so as long as you keep tension on it, you just need to adjust the cam sprocket slightly till the teeth and grooves mesh with the timing mark between the dots (as close to center as you can get it). Once you position the belt properly on the DS cam, place another rag there to hold it. Then the teeth/grooves will hold everything in place while you continue to thread it under the WP and around the PS cam sprocket. Keep up the tension and slightly adjust the cam sprocket like before (on this side, if you can, keep the timing mark between the dots, but biased slightly toward the right). Then go around the tensioner pulley and you should be all set. When you replace the tensioner plunger, it will take up the remaining slack, and it should rotate the PS cam sprocket just enough to center between the dots (this will also snug it up against the WP pulley).
Just keep your hands/fingers on the outside of the belt and there are no worries. My snapped over on me when I was trying to get the right side advanced enough to allow it to come back in the dots after the tensioner was installed.
There is a nice video on youtube done by Grayslater (Cory) that will show you all the ropes.
Lesson learned - do not skip the step where you rotate the crank around a few times to verify that all the dots line up properly after a full rotation.
for the purpose of "bumping" the camshaft to help the sprockets line up with the ribs in the belt, I would suggest using a wrench rather than a socket (especially on the drivers side). If you bump the drivers side over too far with a ratchet and socket then it will quickly spring over to the neutral position where as if you use a wrench then you will have more control over it.
for the purpose of "bumping" the camshaft to help the sprockets line up with the ribs in the belt, I would suggest using a wrench rather than a socket (especially on the drivers side). If you bump the drivers side over too far with a ratchet and socket then it will quickly spring over to the neutral position where as if you use a wrench then you will have more control over it.
That's why Mr. Big Stuff said to use a breaker bar (vs. a ratchet). But you bring up a good point and the point is worth emphasizing, So - yeah - either a box or open end wrench *or* socket with breaker bar.
When I am doing this job, is there anything (besides the water pump, tensioner pulley, and belt) I should change just vecause I will have easy access? Will I have easy access to the thermostat? If so , I think I'll put a new OEM one in. My car runs at perfect temp, but at 140,000 miles the thermostat could go anytime.
I got the car with 136,000 and only recently got in touch with the original owner to find out if the timing belt had been changed. I found out <1k miles ago it had NOT been done. Needless to say I'm doing it ASAP.
Well, your instincts are good. With the radiator fans out, and draining the coolant to change the WP, now is as good of a time as ever to do the thermostat. It's a pain to get to, but some have had success by pulling the alternator (or at least swinging it upwards) and attacking from up top, rather than below.
So, it IS a good time to change the thermostat? Can you give me more information as to what extra work is needed to change it when I have the engine disassembled to the point where I can change the t-belt?
Well, your instincts are good. With the radiator fans out, and draining the coolant to change the WP, now is as good of a time as ever to do the thermostat. It's a pain to get to, but some have had success by pulling the alternator (or at least swinging it upwards) and attacking from up top, rather than below.
I definitely prefer going at it from above. Easier access once you have the alternator out of the way. Make sure you install the new t-stat the correct way (coil into the block). Be aware that there is a small lenght of heater hose (maybe 8-12") from the t-stat housing to the heater return tube. Makes it a bit of a PITA to get the new t-stat in.
When I am doing this job, is there anything (besides the water pump, tensioner pulley, and belt) I should change just vecause I will have easy access? Will I have easy access to the thermostat? If so , I think I'll put a new OEM one in. My car runs at perfect temp, but at 140,000 miles the thermostat could go anytime.
I got the car with 136,000 and only recently got in touch with the original owner to find out if the timing belt had been changed. I found out <1k miles ago it had NOT been done. Needless to say I'm doing it ASAP.
Might also want to do new serpentine and AC belts and tensioner pulleys
My original thermostat went at 200k miles. The rubber seal let go causing it to jam closed. Only go with OEM and make sure you install it correctly. It's different than the way the factory put it in.