C4 Upper Control Arm Shaft Torque
Thread Starter
Instructor
Joined: May 2004
Posts: 105
Likes: 1
Re: C4 Upper Control Arm Shaft Torque (FSTRNU)
Wow, that would be great!
As far as its application to my '84 I would be willing to give it a try. It would at the very least give other folks with a '93 a good ballpark number and could help to collaborate some of the other input that folks have been providing to this thread.
Thanks!
As far as its application to my '84 I would be willing to give it a try. It would at the very least give other folks with a '93 a good ballpark number and could help to collaborate some of the other input that folks have been providing to this thread.
Thanks!
Pro
Joined: Dec 1999
Posts: 559
Likes: 17
From: Coppell TX
Re: C4 Upper Control Arm Shaft Torque (Lister)
Mark the nut so you know how it lines up (scribe it)
loosen the nut, then retighten it with a beam style torque wrench till the mark lines up so the nut is in the same spot. voilia, the factory torque setting(or close)
loosen the nut, then retighten it with a beam style torque wrench till the mark lines up so the nut is in the same spot. voilia, the factory torque setting(or close)
Racer
Joined: Feb 2004
Posts: 334
Likes: 1
From: Fl
Re: C4 Upper Control Arm Shaft Torque (JordonMusser)
Lister, you just did the poly bushingss for the upper? Can you please tell me how these things go together. I have the ES Masterflex kit & the instructions are vague at best & nothing like what came off of there. So it isnt like I can just match up everything.
Also the "breakloose torque" isnt exactly the best way, neither is scribing marks. The break torque I had to use was about 600 ft lbs( 3/4" impact) I know that isnt what is required for tightening.
Also on the scribe marks. If you are using poly bushings, actually any bushings for that matter. They will be different from what was put on originally. The poly bushing wont "crush" so to speak, so the scribe marks wont be correct.
Once I figure out how the firgin bushings go back together. She is getting put back...... goodentight.
thank you all for any help.
Also the "breakloose torque" isnt exactly the best way, neither is scribing marks. The break torque I had to use was about 600 ft lbs( 3/4" impact) I know that isnt what is required for tightening.
Also on the scribe marks. If you are using poly bushings, actually any bushings for that matter. They will be different from what was put on originally. The poly bushing wont "crush" so to speak, so the scribe marks wont be correct.
Once I figure out how the firgin bushings go back together. She is getting put back...... goodentight.
thank you all for any help.
Thread Starter
Instructor
Joined: May 2004
Posts: 105
Likes: 1
Re: C4 Upper Control Arm Shaft Torque (Wheels Up)
Wheels Up, I replaced all the bushings in the front end since I had some bad ball joints that needed replacing and figured that while I had it apart it would be the smart thing to do. I will eventually do the rear as well but they are in pretty good shape. I also have the Energy Suspension HYPER-FLEX Complete Master Bushing set that includes poly bushings for the entire car and I agree that the instructions were a bit vague. Its been quite a while since I actually replaced the bushings (~9 months) and I have had many other things to do on the car since then, so I will have to go out and take a look at it and the instructions to recall what I did. If you can hang in there until this weekend I can probably come up with something that may help.
As for the scribe mark comment, I think that all they were saying was to use that method to figure out what the existing torque setting is and were not inferring to actually use it as a before and after indicator of the correct alignment when replacing the bushings, which I agree would not work.
As for the scribe mark comment, I think that all they were saying was to use that method to figure out what the existing torque setting is and were not inferring to actually use it as a before and after indicator of the correct alignment when replacing the bushings, which I agree would not work.
Racer
Joined: Feb 2004
Posts: 334
Likes: 1
From: Fl
Re: C4 Upper Control Arm Shaft Torque (Lister)
Thank you for the quick reply.
I have been trying to figure this out & may have, but i'm not sure. Does this possibly sound right?
On the UCA the shaft has 2 holes which are not the same size.
I...
1. Put 2 bushings & the sleeve in the smaller hole.
2. Slide the shaft through the big hole.
3. Put the big washer on the shaft. Otherwse it wont fit through the hole :)
4. Put the BIG, 1 piece bushing on the side with the big hole( this is the side that has the small washer like deal on the inside).
5. Put on both big end washers & loc-tite & tighten the crap out of the nuts.
Doing it like this is the only way that makes sense to me, provided with the bushings I have. The LCA doesnt seem to be a problem. Just trying to figure out the UCA.
It seems like you are undertaking something like what i'm undertaking. I'm doing a complete bumper to bumper "resto" if you would. But ther are PLENTY of performance parts.
On the scribe mark.If I read it corectly( again this time). Take a torque wrench & keep going up in torque until the the wrench actually moves the nut? Then tighten it to that torque?
[Modified by Wheels Up, 9:04 PM 5/4/2004]
I have been trying to figure this out & may have, but i'm not sure. Does this possibly sound right?
On the UCA the shaft has 2 holes which are not the same size.
I...
1. Put 2 bushings & the sleeve in the smaller hole.
2. Slide the shaft through the big hole.
3. Put the big washer on the shaft. Otherwse it wont fit through the hole :)
4. Put the BIG, 1 piece bushing on the side with the big hole( this is the side that has the small washer like deal on the inside).
5. Put on both big end washers & loc-tite & tighten the crap out of the nuts.
Doing it like this is the only way that makes sense to me, provided with the bushings I have. The LCA doesnt seem to be a problem. Just trying to figure out the UCA.
It seems like you are undertaking something like what i'm undertaking. I'm doing a complete bumper to bumper "resto" if you would. But ther are PLENTY of performance parts.
On the scribe mark.If I read it corectly( again this time). Take a torque wrench & keep going up in torque until the the wrench actually moves the nut? Then tighten it to that torque?
[Modified by Wheels Up, 9:04 PM 5/4/2004]
Racer
Joined: Oct 2002
Posts: 416
Likes: 2
From: Westfield MA
Re: C4 Upper Control Arm Shaft Torque (Trog)
yup... same here. Except I didn't locktite & had the left work loose. I'm always watching everything though so not a problem. Fine now.
Team Owner
Joined: Sep 2003
Posts: 20,179
Likes: 673
From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
Re: C4 Upper Control Arm Shaft Torque (Lister)
:iagree:
Don't forget that upper pivot arm is aluminum. That nut will stay put with 37 ft/lbs just fine. Locktite is over kill. Just paint a small witness mark on the nuts and check 'em when your checking the oil.
-JRC- :cheers:
[Modified by JrRifleCoach, 6:24 PM 5/4/2004]
Don't forget that upper pivot arm is aluminum. That nut will stay put with 37 ft/lbs just fine. Locktite is over kill. Just paint a small witness mark on the nuts and check 'em when your checking the oil.
-JRC- :cheers:
[Modified by JrRifleCoach, 6:24 PM 5/4/2004]
Drifting
Joined: Jan 2002
Posts: 1,608
Likes: 0
From: I Hate Tourists FL
Re: C4 Upper Control Arm Shaft Torque (SS409 425HP)
yup... same here. Except I didn't locktite & had the left work loose. I'm always watching everything though so not a problem. Fine now.
One thing you can do to"keep an eye" on fasteners that are subject to rotational movement is to use "inspectors laquer". We use it on alot of different fasteners on the helicopters in our hangar. It is basically just thick laquer in a paste form that comes in a small squeeze tube. Its bright yellow and you put a narrow bead down one of the flats on the nut and continue the line onto the exposed bolt threads. If the nut looses torque, it will fracture the dried laquer line and will be easily spotted. The stuff we use is not available at your local parts store, but fingernail polish will work pretty well. Just put it on kind of thick using a small artists brush.
One thing you can do to"keep an eye" on fasteners that are subject to rotational movement is to use "inspectors laquer". We use it on alot of different fasteners on the helicopters in our hangar. It is basically just thick laquer in a paste form that comes in a small squeeze tube. Its bright yellow and you put a narrow bead down one of the flats on the nut and continue the line onto the exposed bolt threads. If the nut looses torque, it will fracture the dried laquer line and will be easily spotted. The stuff we use is not available at your local parts store, but fingernail polish will work pretty well. Just put it on kind of thick using a small artists brush.
I will have to take the car to work and do it one day when its nice. I am scaming the day off tomorrow but will be there on Thur. if its not raining I will take the car in and get an accurate measurement for you.
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Thread Starter
Instructor
Joined: May 2004
Posts: 105
Likes: 1
Re: C4 Upper Control Arm Shaft Torque (FSTRNU)
FSTRNU, thanks I really appreciate it. CV-22 Osprey? Interesting aircraft, are you civilian or are you in the service? I'm ex-USAF and ex-McDonnell Douglas Helicopter (early Apache era before Boeing came along).
Racer
Joined: Oct 2002
Posts: 416
Likes: 2
From: Westfield MA
Re: C4 Upper Control Arm Shaft Torque (FSTRNU)
yup... same here. Except I didn't locktite & had the left work loose. I'm always watching everything though so not a problem. Fine now.
One thing you can do to"keep an eye" on fasteners that are subject to rotational movement is to use "inspectors laquer". We use it on alot of different fasteners on the helicopters in our hangar. It is basically just thick laquer in a paste form that comes in a small squeeze tube. Its bright yellow and you put a narrow bead down one of the flats on the nut and continue the line onto the exposed bolt threads. If the nut looses torque, it will fracture the dried laquer line and will be easily spotted. The stuff we use is not available at your local parts store, but fingernail polish will work pretty well. Just put it on kind of thick using a small artists brush.
We have that stuff all over our airplanes but we call it "bird sheit" and on most of our fittings it doesnt do any good because most of them have been retorqued for leaking anyway. On the CV-22's they are having to use it on every single joint after torque with a calibrated wrench in the witness of an QA inspector, glad I dont work on a test bird anymore!
I will have to take the car to work and do it one day when its nice. I am scaming the day off tomorrow but will be there on Thur. if its not raining I will take the car in and get an accurate measurement for you.
One thing you can do to"keep an eye" on fasteners that are subject to rotational movement is to use "inspectors laquer". We use it on alot of different fasteners on the helicopters in our hangar. It is basically just thick laquer in a paste form that comes in a small squeeze tube. Its bright yellow and you put a narrow bead down one of the flats on the nut and continue the line onto the exposed bolt threads. If the nut looses torque, it will fracture the dried laquer line and will be easily spotted. The stuff we use is not available at your local parts store, but fingernail polish will work pretty well. Just put it on kind of thick using a small artists brush.
We have that stuff all over our airplanes but we call it "bird sheit" and on most of our fittings it doesnt do any good because most of them have been retorqued for leaking anyway. On the CV-22's they are having to use it on every single joint after torque with a calibrated wrench in the witness of an QA inspector, glad I dont work on a test bird anymore!
I will have to take the car to work and do it one day when its nice. I am scaming the day off tomorrow but will be there on Thur. if its not raining I will take the car in and get an accurate measurement for you.
Team Owner
Joined: Sep 2003
Posts: 20,179
Likes: 673
From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
Re: C4 Upper Control Arm Shaft Torque (SS409 425HP)
I've learned one thing about leaks----------------- if a helicopter isn't leaking oil or hyd. fluid somewhere, then its time to reservice it because its all leaked out! I'd be afraid to fly in one that didn't have oil spots under it.
Racer
Joined: Oct 2002
Posts: 416
Likes: 2
From: Westfield MA
Re: C4 Upper Control Arm Shaft Torque (JrRifleCoach)
I've learned one thing about leaks----------------- if a helicopter isn't leaking oil or hyd. fluid somewhere, then its time to reservice it because its all leaked out! I'd be afraid to fly in one that didn't have oil spots under it.
Is this some sort of corrosion protection program? :D
Is this some sort of corrosion protection program? :D
Drifting
Joined: Jan 2002
Posts: 1,608
Likes: 0
From: I Hate Tourists FL
Re: C4 Upper Control Arm Shaft Torque (Lister)
No problem, Yeah I'm a Staff workin with AC-130U's gotta a couple of friends who are on the 22 program both maintenance and acquisition sides. I have heard some stories not as bad now its slowly getting there.
Drifting
Joined: Jan 2002
Posts: 1,608
Likes: 0
From: I Hate Tourists FL
Re: C4 Upper Control Arm Shaft Torque (SS409 425HP)
After 35 years of working on both fixed wing and rotary wing test aircraft, I've learned one thing about leaks----------------- if a helicopter isn't leaking oil or hyd. fluid somewhere, then its time to reservice it because its all leaked out! I'd be afraid to fly in one that didn't have oil spots under it.
[Modified by FSTRNU, 5:35 PM 5/5/2004]
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Re: C4 Upper Control Arm Shaft Torque (SS409 425HP)
if a helicopter isn't leaking oil or hyd. fluid somewhere, then its time to reservice it because its all leaked out! I'd be afraid to fly in one that didn't have oil spots under it.
RACE ON!!!
Race Director
Joined: Dec 2000
Posts: 17,551
Likes: 26
From: El Paso Texas
Re: C4 Upper Control Arm Shaft Torque (CFI-EFI)
if a helicopter isn't leaking oil or hyd. fluid somewhere, then its time to reservice it because its all leaked out! I'd be afraid to fly in one that didn't have oil spots under it. You guys would feel very safe in my car.
RACE ON!!!
RACE ON!!!
Thread Starter
Instructor
Joined: May 2004
Posts: 105
Likes: 1
Re: C4 Upper Control Arm Shaft Torque
Took my car in for a good alignment today at a place that does race car suspensions for SCCA cars and asked the shop owner about the torque on these nuts. He says that off the top of his head he does not recall the actual torque setting but did say that it should be pretty tight and definitely needs to be tight enough to bind against the steel inner bushing sleeve. The reason that it needs to be cinched down tightly is to use the flex in the bushings to augment the spring rate by not allowing it to freely rotate.
2nd Gear
Joined: Sep 2019
Posts: 2
Likes: 0
37-40 ft/lbs seems to be the correct torque spec.
37-40 ft/lbs seems to be the correct torque spec.
as mentioned: the polyurethane bushings should be snug and not flex under torsion.
QUOTE=Lister;1547335650]Took my car in for a good alignment today at a place that does race car suspensions for SCCA cars and asked the shop owner about the torque on these nuts. He says that off the top of his head he does not recall the actual torque setting but did say that it should be pretty tight and definitely needs to be tight enough to bind against the steel inner bushing sleeve. The reason that it needs to be cinched down tightly is to use the flex in the bushings to augment the spring rate by not allowing it to freely rotate.[/QUOTE]
as mentioned: the polyurethane bushings should be snug and not flex under torsion.
QUOTE=Lister;1547335650]Took my car in for a good alignment today at a place that does race car suspensions for SCCA cars and asked the shop owner about the torque on these nuts. He says that off the top of his head he does not recall the actual torque setting but did say that it should be pretty tight and definitely needs to be tight enough to bind against the steel inner bushing sleeve. The reason that it needs to be cinched down tightly is to use the flex in the bushings to augment the spring rate by not allowing it to freely rotate.[/QUOTE]
Intermediate
Joined: Jun 2013
Posts: 32
Likes: 14
From: Los Angeles CA
Uh huh. One more way for the General to stick it to us. The old Corvette Tax. But the fact is that a bazillion aftermarket companies now sell replacement bushings, and it would be nice to finally have a definitive answer on how tight to tighten these things.
What needs to be done is to reverse-engineer this process. If we could get a C4 that has never had this bolt off and measure the torque it takes to break it loose, and then just reset it to that torque value. Too late for me, I did it by the old armstrong method.
Again, 100 ft lbs. My suspension moves just fine, no unusual noises or binding, and I've never had one come loose. As for metal fatigue, get back with me in 10 years and I'll give you an analysis.
What needs to be done is to reverse-engineer this process. If we could get a C4 that has never had this bolt off and measure the torque it takes to break it loose, and then just reset it to that torque value. Too late for me, I did it by the old armstrong method.
Again, 100 ft lbs. My suspension moves just fine, no unusual noises or binding, and I've never had one come loose. As for metal fatigue, get back with me in 10 years and I'll give you an analysis.
I’m at this point on my 96. 100 ft lbs sounds a bit high. I was wondering if you ever got any binding or how the bushings are holding up.On my 99 4x4 Suburban they are 65ft lbs.
