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Old 06-13-2012, 10:53 AM   #1
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To JFP in PA: I too am installing my IMS bearing via the Pelican article and have the sprocket locked with three set screws. Two tensioners are removed as well per the Pelican article. My IMS is also cocked a bit in the case hole.
Now I'm concerned after reading your response below... I currently have a new (pelican) bearing stuck half way in the IMS and hopefully will be pulling it back out when LN sends a hexagon shaft tool to fit the new bearing shaft (ordered it yesterday)... Once/if I get the bearing out is it possible to put tensioners back in (or not) and rotate to TDC? I don't think I want any movement here but need to ask. If this isn't possible then I'm going to make a lock that fits to the engine case and one or two of the bolts on the flywheel flange.
Too bad the LN and Pelican procedures are so different. Seems it can really get us hobbyist in hot water. Appreciate any info you wish to share on my issue. It appears others have been in similar positions. Thank you, Rgs, John mickymingjh@gmail.com
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Old 06-13-2012, 11:00 AM   #2
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Originally Posted by 2000boxster986 View Post
To JFP in PA: I too am installing my IMS bearing via the Pelican article and have the sprocket locked with three set screws. Two tensioners are removed as well per the Pelican article. My IMS is also cocked a bit in the case hole.
Now I'm concerned after reading your response below... I currently have a new (pelican) bearing stuck half way in the IMS and hopefully will be pulling it back out when LN sends a hexagon shaft tool to fit the new bearing shaft (ordered it yesterday)... Once/if I get the bearing out is it possible to put tensioners back in (or not) and rotate to TDC? I don't think I want any movement here but need to ask. If this isn't possible then I'm going to make a lock that fits to the engine case and one or two of the bolts on the flywheel flange.
Too bad the LN and Pelican procedures are so different. Seems it can really get us hobbyist in hot water. Appreciate any info you wish to share on my issue. It appears others have been in similar positions. Thank you, Rgs, John mickymingjh@gmail.com
I got around this by grinding an angle into the ims pulling tool so the bearing would funnel into the cylinder. The funnel straightened the bearing as I pulled it out and once it was most of the way into the removal tool I inserted the set screws. I used an angle grinder to grind the angle into the tool and it turned out pretty precise(for an angle grinder). If your nervous to grind your but want to give it a shot I can send you mine.

I agree with you, it is unfortunate that the LN and pelican procedures are different.
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Last edited by truegearhead; 06-13-2012 at 11:29 AM.
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Old 06-13-2012, 02:25 PM   #3
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Hi Truegearhead. Thank you for the offer. If you have a pic that would be perfect. My removal tool does have a bevel inside to help guide the bearing so I'm thinking this might be what you're referring to, if not a pic would sure be appreciated.

JFP, Thank you, I copy!
The sad part is this; I had TDC locked to begin with (before I stated with the old bearing pull) then I read and re-read the Pelican article and thought I was doing something wrong... so, I switched methods and locked the sprocket once all three holes showed showed some sprocket meat. I figured this method was to prevent having a chain slip at the IMS sprocket so it made sense to lock the sprocket. Now knowing the sprocket is press fit concerns me. The set screws are just hand tight, no more. What further concerns me is the new bearing I now have stuck on the damn IMS. Hopefully the LNE tool will arrive soon so I can get that off and attempt a re-install providing I didn't damage anything. So next would be install the bearing correctly and then try to get the cover back on. So I may have to release the third tensioner to get the IMS to move back to center. I'll try that.
I realize I've followed a procedure here that was supposed to work but it appears to have some issues. Granted more research would have been a good idea... but that didn't happen and now it may backfire, I hope not! I appreciate your expertise and response. Cheers, John
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Old 06-14-2012, 03:34 AM   #4
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Originally Posted by 2000boxster986 View Post
Hi Truegearhead. Thank you for the offer. If you have a pic that would be perfect. My removal tool does have a bevel inside to help guide the bearing so I'm thinking this might be what you're referring to, if not a pic would sure be appreciated.

JFP, Thank you, I copy!
The sad part is this; I had TDC locked to begin with (before I stated with the old bearing pull) then I read and re-read the Pelican article and thought I was doing something wrong... so, I switched methods and locked the sprocket once all three holes showed showed some sprocket meat. I figured this method was to prevent having a chain slip at the IMS sprocket so it made sense to lock the sprocket. Now knowing the sprocket is press fit concerns me. The set screws are just hand tight, no more. What further concerns me is the new bearing I now have stuck on the damn IMS. Hopefully the LNE tool will arrive soon so I can get that off and attempt a re-install providing I didn't damage anything. So next would be install the bearing correctly and then try to get the cover back on. So I may have to release the third tensioner to get the IMS to move back to center. I'll try that.
I realize I've followed a procedure here that was supposed to work but it appears to have some issues. Granted more research would have been a good idea... but that didn't happen and now it may backfire, I hope not! I appreciate your expertise and response. Cheers, John
Mine had a bevel as well and I could feel the bearing pull into the bevel but then stop which is what gave me the idea to cut the sharp angle into the puller. I'll send a pic when I'm able to get back to the garage
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Old 06-14-2012, 06:01 AM   #5
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Pics

Here's the pic of the issue with the bearing. It didn't take much to get it off kilter... It won't move at all. I can rotate the shaft and feel the bearings track so it's under some pressure (or I damaged it). The brace is very similar to what Feelyx used.
Thank you guys for sharing my pain. I'm sure it will be fine as soon as I get that pesky bearing back out.

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Old 06-13-2012, 12:54 PM   #6
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Originally Posted by 2000boxster986 View Post
To JFP in PA: I too am installing my IMS bearing via the Pelican article and have the sprocket locked with three set screws. Two tensioners are removed as well per the Pelican article. My IMS is also cocked a bit in the case hole.
Now I'm concerned after reading your response below... I currently have a new (pelican) bearing stuck half way in the IMS and hopefully will be pulling it back out when LN sends a hexagon shaft tool to fit the new bearing shaft (ordered it yesterday)... Once/if I get the bearing out is it possible to put tensioners back in (or not) and rotate to TDC? I don't think I want any movement here but need to ask. If this isn't possible then I'm going to make a lock that fits to the engine case and one or two of the bolts on the flywheel flange.
Too bad the LN and Pelican procedures are so different. Seems it can really get us hobbyist in hot water. Appreciate any info you wish to share on my issue. It appears others have been in similar positions. Thank you, Rgs, John mickymingjh@gmail.com
There are several large issues here, some involving the board owners, so I will try to “tread lightly” in deference to that.

I do not like the “three set screw” method for exactly the reason I stated; the rear gear on the intermediate shaft is an interference press fit. Pushing on it with threaded devices is asking for trouble. If you dislodge the gear even a little bit by pushing on it with set screws, the rear cam chains will be moved “off axis” towards the case, which is not a good thing as there is no known way to correct this without total disassembly of the engine. Worse yet, using the set screws at all is completely unnecessary if you had followed the LN procedure’s that Jake Raby developed in conjunction with Charles Navarro. Their procedure is slightly more complicated, but it goes smoothly every time.

The reason your shaft is off center is because the remaining tensioner is still loading it, which pulls it to one side. From your question, I have to assume that you are not currently at TDC, and are also not using the cam holding tools. If that is the case, I would not try to reinstall the tensioners you removed and then rotate the crank as the odds are very poor on getting away with that while there is no flange holding the rear of the IMS shaft bearing. Removing the third tensioner might be a better way to get it centered up so you can reassemble everything, but there is also no guarantee on the outcome of that approach.

I really hate to sound so negative about these procedure’s, but unfortunately like most things in life, there is usually one way to do something without encountering issues, and a whole bunch of “short cut” methods to do it that don’t always work out as intended. Some have had good luck using methodology different from LN’s procedures, but not all have been so fortunate, and some have ended up being outright disastrous.
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Old 11-10-2014, 02:34 PM   #7
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I am in a similar situation as others in this thread except that I have not yet extracted the original bearing. I have set screws in place but the bearing is off-center. Only 2 of the 3 tensioners are out. Some ideas for getting the job done from here:

1) Remove 3rd tensioner in attempt to center the bearing in the case hole. Is there significant risk of a timing slip from removing the third tensioner? I have an '01, 5-chain engine.

2) Try to get the engine to TDC, then use cam lock (which came with the ln retrofit kit) and follow ln engineering instructions from the top. To do this, the idea is to reinstall the tensioners and then rotate the engine manually to TDC. JFP stated this is unlikely to work because the flange from the ims bearing is no longer being held in place by the cover. In my case, the old ims bearing is still installed, so I think I have two options to keep it centered while I move to TDC:

a) reinstall the cover. Since the flange is now off-center I'm not sure if this will work. Plus, the flange is broken and would not be able to be secured from the outside of the engine case.

b) use the LN easy-out tool in combination with the removal tool to keep the IMS centered while reinstalling the tensioners and rotating the engine to TDC.

Any feedback on these approaches? I am especially curious about what the risks are when removing the third tensioner--I don't want to mess up the timing.

Image below. FYI, the set screws are just m6 bolts with their heads chopped off:

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Old 11-10-2014, 03:30 PM   #8
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Originally Posted by gonzojive View Post
I am in a similar situation as others in this thread except that I have not yet extracted the original bearing. I have set screws in place but the bearing is off-center. Only 2 of the 3 tensioners are out. Some ideas for getting the job done from here:

1) Remove 3rd tensioner in attempt to center the bearing in the case hole. Is there significant risk of a timing slip from removing the third tensioner? I have an '01, 5-chain engine.

2) Try to get the engine to TDC, then use cam lock (which came with the ln retrofit kit) and follow ln engineering instructions from the top. To do this, the idea is to reinstall the tensioners and then rotate the engine manually to TDC. JFP stated this is unlikely to work because the flange from the ims bearing is no longer being held in place by the cover. In my case, the old ims bearing is still installed, so I think I have two options to keep it centered while I move to TDC:

a) reinstall the cover. Since the flange is now off-center I'm not sure if this will work. Plus, the flange is broken and would not be able to be secured from the outside of the engine case.

b) use the LN easy-out tool in combination with the removal tool to keep the IMS centered while reinstalling the tensioners and rotating the engine to TDC.

Any feedback on these approaches? I am especially curious about what the risks are when removing the third tensioner--I don't want to mess up the timing.

Image below. FYI, the set screws are just m6 bolts with their heads chopped off:

This is a very poor method of securing the IMS during the procedures.

Have you pulled the other two tensioners completely from the engine? Were you on TDC when you began the procedure?

How did you break the flange?
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Old 11-10-2014, 03:50 PM   #9
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This is a very poor method of securing the IMS during the procedures.

Have you pulled the other two tensioners completely from the engine? Were you on TDC when you began the procedure?
I am certainly not disagreeing with you there - should have at least ordered proper set screws. I followed the Pelican Parts guide that uses set screws and doesn't call for starting from TDC.

I was not on TDC when I began the procedure. I initially removed both tensioners completely, though they are now partly screwed in.

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How did you break the flange?
Flange is partly broken because I cut off the nut that was attached to it outside of the engine case. I was not able to rotate the nut with respect to the flange and eventually cut it off because the flathead end of the flange was stripped.
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Old 11-10-2014, 04:39 PM   #10
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I am certainly not disagreeing with you there - should have at least ordered proper set screws. I followed the Pelican Parts guide that uses set screws and doesn't call for starting from TDC.

I was not on TDC when I began the procedure. I initially removed both tensioners completely, though they are now partly screwed in.



Flange is partly broken because I cut off the nut that was attached to it outside of the engine case. I was not able to rotate the nut with respect to the flange and eventually cut it off because the flathead end of the flange was stripped.
Wow... You couldn't hold the center stud while breaking torque on the center nut? Why?

Not starting at TDC is a recipe for disaster. The load from the cams is way too much and overcomes those measley little screws in a heartbeat.

There's one crank position where ALL the cams are unloaded, and that's at TDC.

You will not return the IMS to center withoutbremovingvthe loads from it, so you can't get the flange back on to rotate back to TDC; because you can't center it for re installation.

You now have to re- time the engine from scratch, just like everyone else who pulls the flange at any crank position other than TDC.

I developed the simplest procedure for this, it's been adopted by around 30,000 installers and you never see this post from folks that follow it.
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Old 11-10-2014, 06:07 PM   #11
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Thanks a ton for your help.

Quote:
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Wow... You couldn't hold the center stud while breaking torque on the center nut? Why?
Your understanding is correct. The nut was stuck to the stud. I'm not sure why it was stuck on so tight.

In part I damaged the stud head because I initially used a screwdriver that was too small and stripped the slot. I tried larger screwdrivers and holding the stud head with vice-grips but could not break torque that way. I was stuck on this step for a few days.

One data point, not sure how relevant: The inside of the transmission is very dirty, and it's an '01... perhaps this contributed to the tightness.


Quote:
Originally Posted by Jake Raby View Post
Not starting at TDC is a recipe for disaster. The load from the cams is way too much and overcomes those measley little screws in a heartbeat.

There's one crank position where ALL the cams are unloaded, and that's at TDC.
Thanks for this warning to future readers. Had I read this advice before the install I would have done it the way you describe.

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You will not return the IMS to center without removing the loads from it, so you can't get the flange back on to rotate back to TDC; because you can't center it for re installation.
There are a few things I don't understand here:

1) What is the nature of the load being put on the IMS? Is it bad for any engine component to apply a force opposite to this force?

2) Why is it important that the bearing is centered when rotating back to TDC?

3) In my first post I proposed using the removal tool to center the bearing by overcoming the force from the cams. The large cylinder part of the removal tool could be used to keep the bearing centered while moving the engine back to TDC. What are the issues with this approach?

Quote:
Originally Posted by Jake Raby View Post
You now have to re- time the engine from scratch, just like everyone else who pulls the flange at any crank position other than TDC.
Can you help me understand what exactly has gone wrong that requires retiming from scratch? Have I likely already let the chains slip (even with my 5-chain engine)?

Also, to "re-time from scratch," is it necessary to drop out the engine and take it apart?

Last edited by gonzojive; 11-10-2014 at 06:22 PM. Reason: I was using "flange" incorrectly. The IMS flange is the plate bolted to the case.
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Old 11-10-2014, 08:04 PM   #12
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There are a few things I don't understand here:

1) What is the nature of the load being put on the IMS? Is it bad for any engine component to apply a force opposite to this force?
Whats holding the IMS sideways in the bore is the timing chain for bank 1. That chain has load because at least one pair of cam lobes on that bank are opening valves. If you force the IMS sideways, you are stretching a chain thats already known to stretch and break. I have the only matter linked chains in the world, but they are far from cheap, if you ever need one. Also, never force anything within an engine, if it doesn't want to budge, you must find whats necessary and relieve the tension. If not, you'll be sorry.

Quote:
2) Why is it important that the bearing is centered when rotating back to TDC?
Because rotating the engine ANY from the point you are at now will make the cam timing even worse, and you can crash valves into pistons. You can't get the flange back on to support the IMS, because its no longer centered in the bore, so rotating an unsupported IMS is a recipe for bigger disaster.

Quote:
3) In my first post I proposed using the removal tool to center the bearing by overcoming the force from the cams. The large cylinder part of the removal tool could be used to keep the bearing centered while moving the engine back to TDC. What are the issues with this approach?
I invented and developed that tool, this was never its intended purpose. That said, you do not know how far out the cams are at the present, and you won't know if things will crash until you move the engine. Not saying this won't work, but I am saying that its not a smart approach.

Quote:
Can you help me understand what exactly has gone wrong that requires retiming from scratch? Have I likely already let the chains slip (even with my 5-chain engine)?
The entire valve drive system has shifted when the flange was removed without the engine being at TDC and having the CAMS locked. Something had to move when the flange was removed, and its likely retarding bank 1. This means that the exhaust valves on that bank can crash into the pistons fairly easily, and you don't want to risk that.

Quote:
Also, to "re-time from scratch," is it necessary to drop out the engine and take it apart?
No, it can be done in the chassis, engine assembled. Pull both cam covers, and have fun.

Now, do you guys see why we only sell our IMSR products through distributors supplying them to professionals? This sort of thing should be avoided at all costs, and this is not a job for the faint of heart. The learning curve is 90 degrees, and using a procedure that looks good on paper, is a lot different than one that was developed in the real world from trial and error.

I've made lots of errors, but thats what happens when you blaze the trail that leads to the super highway that everyone else decides to travel.
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