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Discussion Starter · #1 ·
I'm in the middle of changing the cam belts on my '99 Esprit and ran into what could be a major problem. I installed both new Gates blue belts and was starting to rotate the crank twice to verify the tolerence pins would still go in. The right side belt jumped a tooth (or two, no way to tell) after it was less than 1/4th of the way through the first revolution. I guess I didn't tighten the tensioner pulley enough on that bank. Anyway, I'm unsure how to continue. Do I need to follow the service notes and reindex the cams (they don't give any indication on how to get the engine into the "safe" position when it's out of sync. If I continue to rotate the crank it hits a valve) or can I rotate the crank counter-clockwise until I can put the tolerence pins back in, remove the belt on that side, and continue to rotate the crank until I can get the crank locking tool in place. I assume rotating the crank counter-clockwise is a no-no, but I'm not sure why other than the risk of loosening the crank bolt. The left bank is fine.
Any ideas would be appreciated!
 

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Discussion Starter · #6 ·
@04ESPRIT - I happen to have a borescope, so using it to make sure the cams are close to the locking position is a done deal. I've already used it to look down the sparkplug holes to check out the tops of the pistons. It's a very cool piece of equipment! The only way I can think to reset the cam timing without rotating the crank counter clockwise is to remove them. Otherwise I can't move the crank without valve/piston contact. I didn't see anything in the service guide about how to do this, but I haven't spent a lot of time looking yet.

@DailyDriver - I have removed the sparkpulugs, so turning the crank is fairly easy. I am using the ARP bolts that came with the kit I got from JAE, they’re much better than the factory bolts! I had spent a lot of time getting to this point and like a friggin idiot didn’t fully tighten the tensioner pulley before I moved the crank. This is what happens when you step away from a project mid-way through and come back to it weeks later… live and learn!
 

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Discussion Starter · #8 ·
A quick update - I was able to recover from my mistake and get all the setting pins installed and the crank locked after rotating the crank counter clockwise. I was able to set the tension (it settled at 118 Hz left, 108 Hz right) on the new blue belts (new idlers and tensioners as well) after three tries. I checked that the setting pins went in with the crank locked before moving to the two tension setting positions each time I adjusted the tensioners. The last go-round three of the pins went in with no friction, but the left intake side required me to wiggle it a bit before it was fully seated. After the serpentine belt went in I started it, and heard a loud ticking sound. I shut it off after about 10 seconds. I looked around the engine bay and couldn’t see anything, so started it up again for about 10 seconds. Still ticked… The engine hadn’t been run for a few months, not sure if this has anything to do with the noise. I can’t work on the car until Monday, but I’m planning to pull the spark plugs and use my bore scope to see if any of the valves hit the pistons. Not sure how it could happen, but I don’t know what else to do. Any thoughts on what would cause this would be appreciated!
 

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Discussion Starter · #15 ·
When I started it up it ran fine, smooth idle and no unusual exhaust note. I think I’m going start it up again tomorrow and let it run for a minute or two after I check all the bolts on the pulleys and bearings. I hope it’s just lifter tick!
 

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Discussion Starter · #17 ·
I just ran a compression test on each cylinder and it doesn’t look too bad. On the drivers side, front to back I got 160, 150, 175, and 175. The passenger side is a bit lower at 155, 150, 160, and 150. Do these numbers seem reasonable? I started it up again and let it run for about a minute, the tick is still there. It idles fine but stumbled a bit when I gave it gas. I looked in each cylinder with a bore scope and didn’t fine evidence of valve to piston contact. The cylinders still have a nice cross hatch on them. I just got a leakdown tester, I think that will be my next test unless someone has a better idea!
 

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Discussion Starter · #19 ·
@DailyDriver - I haven’t run it for more than 90 seconds so far. I’ll put the plugs back in and let it warm up for a few minutes. I can’t pinpoint where the noise is coming from, but I have a stethoscope on order that should help. I noticed something odd though. The new serpentine belt has shallow groves in it. Nothing is rubbing on it and the tensioner is clean. Very odd as I confirmed it’s routed correctly.
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Discussion Starter · #24 ·
@esprit888 - I agree, it looks like the smooth side of the belt is rubbing against a grooved pulley, but I’ve looked at every contact point and am certain that’s not what’s causing it. The indentations are much closer together than the groves on the pulleys, plus they’re really shallow. It’s not getting any worse, so I’m going to buy a new belt and keep an eye on it.
@Add Lightness - the tapping was so loud I was certain a valve was smacking into a piston, which kinda freaked me out. Lesson learned, next time I‘ll let it run a bit before I panic. At the end of the day I’m not sure I even needed to change the belts. Sure, they were eight years old, but they look perfect. The serpentine belt was cracked all over the inside, so I’m glad I replaced it. All the bearings were turning freely, I’m not sure they needed to be replaced either. I’d love to send the belts out to have them tested to see how much life is left in them. I know belt change intervals are a hot topic, but I’ve yet to hear definitive info on how long the Gates blue belts should last. Lotus changed their guidance several times, so maybe no one really knows… my plan is to run the new belts at least five years, maybe seven depending on my tolerance for the risk of them breaking.
@jtrealty - do you have a recommendation on which engine flush to use? I‘ve never used them.
 
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