Vibration at 2900-3100 rpm
09-04-2003, 12:31 AM
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Vibration at 2900-3100 rpm
I have a 91 S4, in good condition. When it reached about 40,000 miles it developed a vibration in the drive train at 2900-3100 rpm. That was 3 years ago. I have replaced the timing belt, engine mounts, wires, coils and some of my hair. The vibration is almost like going over mild rumble strips on the side of the road. It goes away above 3100. It doesent matter what gear. Could it be a harmonic vibration? Bad vibrtation dampner?
Any ideas would be helpful.
Thanks
Paul Farmer
Any ideas would be helpful.
Thanks
Paul Farmer
09-04-2003, 12:44 AM
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Paul,
Have you done the "Loctite Fix"?
http://www.nichols.nu/tip598.htm
http://members.rennlist.com/v1uhoh/cranksha.htm
Have you done the "Loctite Fix"?
http://www.nichols.nu/tip598.htm
http://members.rennlist.com/v1uhoh/cranksha.htm
09-04-2003, 01:08 AM
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If it's ONLY dependant on engine speed, the vibration has to be in your engine, not your suspension, transmission or torque tube. Look at your auxillary drives like your AC compressor, air pump, and power steering pump. I assume that changing the mounts didn't change the frequency of the vibration. It's unlikely that it's the harmonic ballancer if it started after 40,000 miles.
09-04-2003, 10:23 AM
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I have a very similar vibration problem and my TT is fairly new.
I disagree with Ernest it could be the TT, since it always spins at the engine's RPM. That makes it even harder to troubleshoot.
In my case I had the harmonic ballancer fall off due to a negligent repair shop in Miami forgetting to torque it down after work they had performed.
Could it have gotten damaged and cause my vibration?
I disagree with Ernest it could be the TT, since it always spins at the engine's RPM. That makes it even harder to troubleshoot.
In my case I had the harmonic ballancer fall off due to a negligent repair shop in Miami forgetting to torque it down after work they had performed.
Could it have gotten damaged and cause my vibration?
09-04-2003, 11:09 AM
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Paul,
The "Loctite Fix" was developed about 4 years ago on 4 speed automatics to try to reduce crankshaft thrust bearing failure. As a byproduct, it seems to reduce or eliminate a vibration at about 3,000 rpm. This writeup was on Nichols site but seems to have been truncated. Try it. It is cheap and has worked on other cars and may save your engine also. Tony's site has a good writeup and pictures.
This is a "final" report on the Flexplate hub Loctite test. ---It works.
Background: The engine crankshaft thrust bearing has worn out on some
automatic transmission cars. There is much speculation on the cause of TBF
(thrust bearing failure) There are many possibilities. One of the
possibilities is the migration of the front flexplate hub, causing constant
pressure on the thrust bearing. "Stuttgart Mechanics," whoever they are,
suggested increasing the torque on the hub pinch bolt by 10% (torque to 110%
of recommended torque). We found that this did not stop the migration.
Test: I tried using penetrating Loctite (290) on the hub splines. This has
been tried on at least 10 cars and has been successful. I have not heard of
any hub movement after using Loctite.
Results: Loctite seems to be able to stop the hub movement. The pressure
against the TB is significant, you can't check for wear until you release the
pressure. The TB wear on the 4 cars that I checked was within factory
specifications, so presumably the pressure was not causing a problem.
One byproduct of eliminating the pressure on the crankshaft is: It may reduce
or eliminate a vibration that happens at ~3050 RPM. Even if it doesn't help
the TBF problem, maybe it will stop potential problems from the vibration?
Could this also cause the TT bearings to fail?
Recommendations: Porsche designed the hub to not move. It is moving, and
putting pressure against the TB. The "Loctite Fix" is cheap insurance. If you
have an automatic, why not do it? While you are down there check the rear
pinch bolt, I hear that they can loosen up and cause the driveshaft splines
to strip. Maybe the hub movement causes the rear bolt to work loose? One car
had worn threads on the rear pinch bolt, so maybe it is a good idea to
replace both pinch bolts. P/N 931.412.240.00 and install with Loctite 242.
Please do NOT think that this is "THE FIX" for TBF. This is one of the
possibilities. One other possibility that has not been brought up on the list
is torque converter "balooning". Apparently other manufacturers have seen TBF
caused by failed torque converters. It would be interesting to know if
Mercedes ever has this problem. I have heard that it happens on Chevys or is
that Chebbys? I have heard the advice that if you replace the torque tube,
then while you are in there, replace the torque converter bearings. Why? Do
they go bad? Is this insurance against "balooning"?
Constantine's sliding coupling could reduce the possibility of TBF much more.
If "balooning" is a problem, can the coupling slide enough to compensate? If
your torque tube needs replacement, then that would be a good time to install
the sliding coupling. Just a little more insurance.
Loctite Procedure:
1) Drop the exhaust at the manifolds. (this may not be necessary on some cars)
2) Remove the bell housing bottom cover.
3) If you want to measure the amount of movement of the flexplate hub, put a
dial indicator on the forward side of the hub. Or you can measure the amount
drive shaft spline visible on the rear side of the hub, before and after
loosening the hub clamp screw.
4) Loosen the hub clamp screw and watch for hub movement.
With the front hub clamp screw loose you can check for TB wear and also
tighten or replace the rear clamp screw. Note: Tightening the rear clamp
screw with the front clamp screw tight and with preload may be why the rear
clamp screw threads are damaged.
Replace the rear clamp screw (same P/N as front, P/N 931.421.240.00). Remove
the rubber plug in the rear end of the TT. Rotate engine until the bolt is
visible. See shop manual page 37- 4 #14. use Loctite 242, torque to 65 ftlb.
Check crankshaft end play:
Install dial indicator on flywheel and carefully pry the flywheel back and
forth. You may be able to check this measurement with a dial caliper or
vernier caliper. The spec for later engines is .0024" to .0076". Wear limit
is .016". Metric .110 to .312. wear limit .4.
5) Before installing the front clamp screw, pour Loctite 290 penetrating
formula in the slots in the hub.
6) Install new front clamp screw P/N 231.421.240.00 using Loctite 242 and
torque to 65 ftlb. It would be logical to pry the crankshaft back before
tightening the bolt, but I don't think that it matters. The flexplate
provides for plenty of "float".
7) Paint the shaft splines white on the rear side of the hub. Then whenever
you have the car up in the air you can look through the hole on the bottom of
the bell housing and see if it has moved. An inexpensive fiber optic extender
on a penlight can give you better visibility. They are available at
hardware/home center stores ~$5.00.
8) Reinstall bellhousing bottom cover and exhaust.
Loctite says that it takes 24 hours to cure. If you can't wait 24 hours
before driving the car, I would wait at least 1 hour and then drive gently
for the first 24 hours. I know that is a lot to ask, but do it.
It's probably a good idea to periodically check crankshaft end play. If the
hub has not moved, you can check end play without loosening the clamp bolt.
The thrust plate flexibility easily allows back and forth movement of the
crankshaft.
Earl Gillstrom '88 5Speed
The "Loctite Fix" was developed about 4 years ago on 4 speed automatics to try to reduce crankshaft thrust bearing failure. As a byproduct, it seems to reduce or eliminate a vibration at about 3,000 rpm. This writeup was on Nichols site but seems to have been truncated. Try it. It is cheap and has worked on other cars and may save your engine also. Tony's site has a good writeup and pictures.
This is a "final" report on the Flexplate hub Loctite test. ---It works.
Background: The engine crankshaft thrust bearing has worn out on some
automatic transmission cars. There is much speculation on the cause of TBF
(thrust bearing failure) There are many possibilities. One of the
possibilities is the migration of the front flexplate hub, causing constant
pressure on the thrust bearing. "Stuttgart Mechanics," whoever they are,
suggested increasing the torque on the hub pinch bolt by 10% (torque to 110%
of recommended torque). We found that this did not stop the migration.
Test: I tried using penetrating Loctite (290) on the hub splines. This has
been tried on at least 10 cars and has been successful. I have not heard of
any hub movement after using Loctite.
Results: Loctite seems to be able to stop the hub movement. The pressure
against the TB is significant, you can't check for wear until you release the
pressure. The TB wear on the 4 cars that I checked was within factory
specifications, so presumably the pressure was not causing a problem.
One byproduct of eliminating the pressure on the crankshaft is: It may reduce
or eliminate a vibration that happens at ~3050 RPM. Even if it doesn't help
the TBF problem, maybe it will stop potential problems from the vibration?
Could this also cause the TT bearings to fail?
Recommendations: Porsche designed the hub to not move. It is moving, and
putting pressure against the TB. The "Loctite Fix" is cheap insurance. If you
have an automatic, why not do it? While you are down there check the rear
pinch bolt, I hear that they can loosen up and cause the driveshaft splines
to strip. Maybe the hub movement causes the rear bolt to work loose? One car
had worn threads on the rear pinch bolt, so maybe it is a good idea to
replace both pinch bolts. P/N 931.412.240.00 and install with Loctite 242.
Please do NOT think that this is "THE FIX" for TBF. This is one of the
possibilities. One other possibility that has not been brought up on the list
is torque converter "balooning". Apparently other manufacturers have seen TBF
caused by failed torque converters. It would be interesting to know if
Mercedes ever has this problem. I have heard that it happens on Chevys or is
that Chebbys? I have heard the advice that if you replace the torque tube,
then while you are in there, replace the torque converter bearings. Why? Do
they go bad? Is this insurance against "balooning"?
Constantine's sliding coupling could reduce the possibility of TBF much more.
If "balooning" is a problem, can the coupling slide enough to compensate? If
your torque tube needs replacement, then that would be a good time to install
the sliding coupling. Just a little more insurance.
Loctite Procedure:
1) Drop the exhaust at the manifolds. (this may not be necessary on some cars)
2) Remove the bell housing bottom cover.
3) If you want to measure the amount of movement of the flexplate hub, put a
dial indicator on the forward side of the hub. Or you can measure the amount
drive shaft spline visible on the rear side of the hub, before and after
loosening the hub clamp screw.
4) Loosen the hub clamp screw and watch for hub movement.
With the front hub clamp screw loose you can check for TB wear and also
tighten or replace the rear clamp screw. Note: Tightening the rear clamp
screw with the front clamp screw tight and with preload may be why the rear
clamp screw threads are damaged.
Replace the rear clamp screw (same P/N as front, P/N 931.421.240.00). Remove
the rubber plug in the rear end of the TT. Rotate engine until the bolt is
visible. See shop manual page 37- 4 #14. use Loctite 242, torque to 65 ftlb.
Check crankshaft end play:
Install dial indicator on flywheel and carefully pry the flywheel back and
forth. You may be able to check this measurement with a dial caliper or
vernier caliper. The spec for later engines is .0024" to .0076". Wear limit
is .016". Metric .110 to .312. wear limit .4.
5) Before installing the front clamp screw, pour Loctite 290 penetrating
formula in the slots in the hub.
6) Install new front clamp screw P/N 231.421.240.00 using Loctite 242 and
torque to 65 ftlb. It would be logical to pry the crankshaft back before
tightening the bolt, but I don't think that it matters. The flexplate
provides for plenty of "float".
7) Paint the shaft splines white on the rear side of the hub. Then whenever
you have the car up in the air you can look through the hole on the bottom of
the bell housing and see if it has moved. An inexpensive fiber optic extender
on a penlight can give you better visibility. They are available at
hardware/home center stores ~$5.00.
8) Reinstall bellhousing bottom cover and exhaust.
Loctite says that it takes 24 hours to cure. If you can't wait 24 hours
before driving the car, I would wait at least 1 hour and then drive gently
for the first 24 hours. I know that is a lot to ask, but do it.
It's probably a good idea to periodically check crankshaft end play. If the
hub has not moved, you can check end play without loosening the clamp bolt.
The thrust plate flexibility easily allows back and forth movement of the
crankshaft.
Earl Gillstrom '88 5Speed
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09-04-2003, 02:08 PM
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Hi 928 experts
The same discussion was up last week, see: https://rennlist.com/forums/showthre...hreadid=86110, There I asked Wally several question, and gave my comments, but I never got any answers - I try again:
Earl and Steve made two good write up, as usual when they lead 'the pen'
But there are several things/theories I do not understand, hopefully someone can give me a logic explanation/comments for the followings:
1. What is the logic explanation that 'the Loctite fix' can solve the 3000 RPM vibration problem?
2. There is a lot of talking about the ballooning theory - I fully accept his on a Mercedes Benz where the converter is mounted direct on the fly-wheels, but on a 928 we have the converter shaft and two flex-plates placed in-between. The converter shaft is held in place of two bearings who cannot move forwards, I.e only if these two bearings have axial play, the converter shaft and, with this, the trans shaft can move forwards.
3. As I understood, the problem with the forwards moving trans-axel and trust bearing problem only exist on the latest models. On some of these late model cars we even see broken trans-shaft. This can only be due to the increased engine torque
The first model had 375 Nm and the latest 500 Nm = 35% increase, and according to my knowledge the shaft diameter is the same.
What happen to the shaft before it breaks?
A lot of winding and unwinding - I think that can be the reason for the 'forwards movement' simply because the shaft grows in length before it break
PS: See the photo of a broken trans-shaft from a Danish GTS:
http://boards.rennlist.com/upload/trans-shaft.JPG
The same discussion was up last week, see: https://rennlist.com/forums/showthre...hreadid=86110, There I asked Wally several question, and gave my comments, but I never got any answers - I try again:
Earl and Steve made two good write up, as usual when they lead 'the pen'
But there are several things/theories I do not understand, hopefully someone can give me a logic explanation/comments for the followings:
1. What is the logic explanation that 'the Loctite fix' can solve the 3000 RPM vibration problem?
2. There is a lot of talking about the ballooning theory - I fully accept his on a Mercedes Benz where the converter is mounted direct on the fly-wheels, but on a 928 we have the converter shaft and two flex-plates placed in-between. The converter shaft is held in place of two bearings who cannot move forwards, I.e only if these two bearings have axial play, the converter shaft and, with this, the trans shaft can move forwards.
3. As I understood, the problem with the forwards moving trans-axel and trust bearing problem only exist on the latest models. On some of these late model cars we even see broken trans-shaft. This can only be due to the increased engine torque
The first model had 375 Nm and the latest 500 Nm = 35% increase, and according to my knowledge the shaft diameter is the same.
What happen to the shaft before it breaks?
A lot of winding and unwinding - I think that can be the reason for the 'forwards movement' simply because the shaft grows in length before it break
PS: See the photo of a broken trans-shaft from a Danish GTS:
http://boards.rennlist.com/upload/trans-shaft.JPG
Last edited by Erik - Denmark; 09-04-2003 at 02:25 PM.
09-04-2003, 06:45 PM
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Erik,
As far as I know, nobody has ever identified the "problem". If you don't know what the problem is, you can't fix it. I was trying to solve a symptom of the "problem" with the "Loctite Fix". As a byproduct of the "Loctite Fix", the vibration at ~3000 rpm seems to deminish or dissappear. On some cars, I have seen the front flexplate hub pressed very hard against the flywheel. That pressure probably causes the vibration as well as wearing the thrust bearing in the engine, although I have never seen a worn thrust bearing in one of these cars. It is all a mystery to me.
As far as the driveshaft breaking on latest cars. Porsche says that it can be caused by running on 4 cylinders if you have an ignition failure. That makes sense to me when I think about the mass of a torque converter on the end of a 10' shaft trying to smooth out a rough running engine. Keep in mind that the flywheel on auto cars is very light and the torque converter weight is additional flywheel weight. That extra weight is normally bolted directly to the flywheel, but on a 928 is on the other end of the car.
As far as I know, nobody has ever identified the "problem". If you don't know what the problem is, you can't fix it. I was trying to solve a symptom of the "problem" with the "Loctite Fix". As a byproduct of the "Loctite Fix", the vibration at ~3000 rpm seems to deminish or dissappear. On some cars, I have seen the front flexplate hub pressed very hard against the flywheel. That pressure probably causes the vibration as well as wearing the thrust bearing in the engine, although I have never seen a worn thrust bearing in one of these cars. It is all a mystery to me.
As far as the driveshaft breaking on latest cars. Porsche says that it can be caused by running on 4 cylinders if you have an ignition failure. That makes sense to me when I think about the mass of a torque converter on the end of a 10' shaft trying to smooth out a rough running engine. Keep in mind that the flywheel on auto cars is very light and the torque converter weight is additional flywheel weight. That extra weight is normally bolted directly to the flywheel, but on a 928 is on the other end of the car.
09-04-2003, 07:57 PM
#10
Drifting
Erik,
Having personally replaced the torque tube on my 90' S4 Automatic, I have concluded that the shaft pressure buildup/movement in the couplings is due to corrosion of the central shaft and coupling splines.
Based on my engineering background, I suggest that if the both central shaft couplings are properly lubricated per the shop manual (pg. 37-121, Installing Automatic Transmission, Step 1, “coat splines on central shaft with Optimoly HT”), and that the couplings are torqued to the shop manual specified value, the central shaft should not build up axial pressure against the crankshaft thrust bearing.
Positioning the crankshaft at the midpoint of the crankshaft thrust bearing should be done using a dial indicator prior to tightening both front and rear central shaft couplings.
Having personally replaced the torque tube on my 90' S4 Automatic, I have concluded that the shaft pressure buildup/movement in the couplings is due to corrosion of the central shaft and coupling splines.
Based on my engineering background, I suggest that if the both central shaft couplings are properly lubricated per the shop manual (pg. 37-121, Installing Automatic Transmission, Step 1, “coat splines on central shaft with Optimoly HT”), and that the couplings are torqued to the shop manual specified value, the central shaft should not build up axial pressure against the crankshaft thrust bearing.
Positioning the crankshaft at the midpoint of the crankshaft thrust bearing should be done using a dial indicator prior to tightening both front and rear central shaft couplings.
09-05-2003, 06:47 AM
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Earl and Borland
Thanks for your comments
Earl,
I do not have a pressure on my flex plate, but I do have the 3000 RPM vibration (My car is the latest model using the X-shims method - I.e. I have a negative pressure on my crankshaft)
Few months ago, there was a discussion started of Thom1 about the same problem, here DoubleNutz concluded that was due to trans shaft bearing moving backwards, with the fix to install one more bearing, and this one more to be installed with the trans shaft in place (I do not know if it is possible or not I never BTDT - But see: https://rennlist.com/forums/showthre...ation+at+speed
Can the logic explanation be that problem starts with a transaxle bearing mowing backwards, I.e. the shaft loose some of its support and start swinging at 3000 RPM due to own frequency area. By this the shaft are getting shorter and pulling backward at front splines/coupling and when the vibration is over the shaft pulls the flex plate?
(My thinking is that it can move backwards in the splines due to the vibration but cannot move back again without vibration)
If yes, then the maybe 'Loctite fix' can prevent the shaft to move backwards duing the vibration period and maybe even prevent the vibration?
It would be interesting to hear more about DoubleNut's 'miracle cure' with the extra bearing
Regarding the braking trans-shaft I find the Porsche excuse doubtful - How many cars are running with only four cylinders
I could be interesting to hear from 928 owners who have had that accident - I know one, Michael in Copenhagen - What was the result of your research work?
Borland
Actually your theory draw in the other direction, because rusty splines/clutch should be equal to Loctided splines (grown solid)
As Earl said, no one has ever identified the problem, but I am sure with common input, we can find the logic explanation for this strange problem
Thanks for your comments
Earl,
I do not have a pressure on my flex plate, but I do have the 3000 RPM vibration (My car is the latest model using the X-shims method - I.e. I have a negative pressure on my crankshaft)
Few months ago, there was a discussion started of Thom1 about the same problem, here DoubleNutz concluded that was due to trans shaft bearing moving backwards, with the fix to install one more bearing, and this one more to be installed with the trans shaft in place (I do not know if it is possible or not I never BTDT - But see: https://rennlist.com/forums/showthre...ation+at+speed
Can the logic explanation be that problem starts with a transaxle bearing mowing backwards, I.e. the shaft loose some of its support and start swinging at 3000 RPM due to own frequency area. By this the shaft are getting shorter and pulling backward at front splines/coupling and when the vibration is over the shaft pulls the flex plate?
(My thinking is that it can move backwards in the splines due to the vibration but cannot move back again without vibration)
If yes, then the maybe 'Loctite fix' can prevent the shaft to move backwards duing the vibration period and maybe even prevent the vibration?
It would be interesting to hear more about DoubleNut's 'miracle cure' with the extra bearing
Regarding the braking trans-shaft I find the Porsche excuse doubtful - How many cars are running with only four cylinders
I could be interesting to hear from 928 owners who have had that accident - I know one, Michael in Copenhagen - What was the result of your research work?
Borland
Actually your theory draw in the other direction, because rusty splines/clutch should be equal to Loctided splines (grown solid)
As Earl said, no one has ever identified the problem, but I am sure with common input, we can find the logic explanation for this strange problem
09-05-2003, 11:01 AM
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Borland,
Have you checked your front flexplate hub position since you installed the torque tube? I found without the Loctite that the hub would move forward in a few hundred miles. You are suggesting that the hub will slide back and forth on the shaft with the proper lubrication?
Erik,
The TT bearing migration is a good possibility for the vibration and increase in vibration when the hub is forward. I thought that the migration was only happening on the 4 speed auto later cars. Is it happening on your car?
I am sure that Porsche identified this problem but kept it secret so they would not have to fix it under warranty or recall.
Constantine was developing a sliding spline fix a few years ago, but I don't know the status.
Have you checked your front flexplate hub position since you installed the torque tube? I found without the Loctite that the hub would move forward in a few hundred miles. You are suggesting that the hub will slide back and forth on the shaft with the proper lubrication?
Erik,
The TT bearing migration is a good possibility for the vibration and increase in vibration when the hub is forward. I thought that the migration was only happening on the 4 speed auto later cars. Is it happening on your car?
I am sure that Porsche identified this problem but kept it secret so they would not have to fix it under warranty or recall.
Constantine was developing a sliding spline fix a few years ago, but I don't know the status.
09-05-2003, 02:19 PM
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Originally posted by Earl Gillstrom
........The TT bearing migration is a good possibility for the vibration and increase in vibration when the hub is forward. I thought that the migration was only happening on the 4 speed auto later cars. Is it happening on your car?
[/B]
........The TT bearing migration is a good possibility for the vibration and increase in vibration when the hub is forward. I thought that the migration was only happening on the 4 speed auto later cars. Is it happening on your car?
[/B]
I don't know if I have this problem I never touch the trans shaft, but I know I have the 3000 RPM vibration problem
I have the theory (with the sliding bearing) from DoubleNuts, see the above mentioned link
Hopefully DoubleNuts will jump into this discussion
As you know I have an professional 'sponsor', this afternoon I discussed that with him, he said are you sure that's not the two rear joint-shaft (Years ago he was a SAAB dealer and here it was normal to change left and right after about 100,000 Km (60,000 Miles) - We will check that tomorrow - First we have to check did I have the vibration in all gears or only in 4th gear - I think I only have it in 4th gear and then it can be these shaft.
09-05-2003, 03:22 PM
#14
USMarine
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Originally posted by Scott C
NHH,
Not to diminish your dilemma, but I'd put $20 that your torque tube in question.
Is your car AT or 5-sp?
NHH,
Not to diminish your dilemma, but I'd put $20 that your torque tube in question.
Is your car AT or 5-sp?
Either they have walked back or they are completely wiped out buy the whipping of the shaft
p@
09-05-2003, 03:29 PM
#15
Drifting
Earl,
I have less than 500 miles on the car since I installed the TT, but I have no plans to check for forward movement at this time.
I believe that if the shaft can move forwards, it should move backwards as well and establish a point of equilibrium.
However if there is corrosion (rust) in the splines, then the static friction would be orders of magnatude higher than a lubricated one. Any shaft movement, due to thermal expansion (minimal), shaft vibration, and crankshaft end play would only happen when the forces exceed the static friction of the mating spline surfaces. Apparently, the magnatitude of the forces forward exceed those toward the rear (but I can't find any technical support for the shaft stretching under torsion). And it is likely that the flex plate has a natural harmonic frequency which contributes to this. This assumes that the two deep grooved torque converter bearings have not deteriorated significantly.
It could be that your Loctite procedure may introduce additional vibration or crankshaft thrust bearing wear if the crankshaft is not positioned properly prior to tightening the coupling bolts.
I have less than 500 miles on the car since I installed the TT, but I have no plans to check for forward movement at this time.
I believe that if the shaft can move forwards, it should move backwards as well and establish a point of equilibrium.
However if there is corrosion (rust) in the splines, then the static friction would be orders of magnatude higher than a lubricated one. Any shaft movement, due to thermal expansion (minimal), shaft vibration, and crankshaft end play would only happen when the forces exceed the static friction of the mating spline surfaces. Apparently, the magnatitude of the forces forward exceed those toward the rear (but I can't find any technical support for the shaft stretching under torsion). And it is likely that the flex plate has a natural harmonic frequency which contributes to this. This assumes that the two deep grooved torque converter bearings have not deteriorated significantly.
It could be that your Loctite procedure may introduce additional vibration or crankshaft thrust bearing wear if the crankshaft is not positioned properly prior to tightening the coupling bolts.