Advice on removing coil spring from suspension strut

decampos

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assembly.jpg


I can't figure out how to remove the top cap to remove the coil spring (I'm replacing them). The OWM says ( http://www.e9coupe.com/tech/autobooks/chapter9/autobooks_manual_100.htm) I just need to 'Unscrew the locknut'. I have a Hayne's manual and it says: 'hold the piston rod still with a spanner and unscrew the self-locking nut'.

end_cap.jpg


The nut and (presumably) the piston rod are fairly recessed deep into it and I cannot get two spanners onto either the nut or the piston rod. All I can do is get a socket onto the nut but obviously I'm not able to hold the piston rod still.

Any idea how I do this? Am I going about this all wrong?

Any help very much appreciated.

strut.jpg
 
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Special tool...

I got a cheap socket to fit the strut top nut, and a cheap box wrench. paid a local welder $15 to cut off the "drive" end of the socket and weld it onto the box wrench.
this let's you get the socket onto the nut but it's still open at the top for a second wrench or socket on the strut rod.

it's just a poor-man's very offset box wrench

John
 
Yeah, these are a B*TCH to get apart. Usually the big nut is loosened while the strut is still on/in the car. It was intended to hold the small hex and use a deep offset wrench to loosen the big nut.

You MUST first compress the spring before taking off the big nut. If you don't, when the nut comes off the spring will send the top strut mount flying. Fast. Someone, maybe you, can get hurt.

Option 1: (after compressing the spring) use an 1/2" drive impact gun on the large top nut

Option 2: (after compressing the spring) hold the smaller hex with a 1/4" drive socket then remove the large nut with a socket held in vise grips.

Option 3: take it to a shop that does supension work and let them compress the spring and remove the nut. They will have the equipment to do this quickly, safely and hopefully inexpensively.
 
Hi John. Thanks for your reply. That's interesting and a bit of a bummer. So there's no trick to it and I gotta fabricate an odd tool? Do you know what is the actual tool to use is? Seems odd that the workshop manual and the haynes manual didn't flag anything here.
Thanks
Ben

I got a cheap socket to fit the strut top nut, and a cheap box wrench. paid a local welder $15 to cut off the "drive" end of the socket and weld it onto the box wrench.
this let's you get the socket onto the nut but it's still open at the top for a second wrench or socket on the strut rod.

it's just a poor-man's very offset box wrench

John
 
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Thanks for your reply Honolulu. It's difficult to see in the photograph but there are spring compressors in place.

Option 1: (after compressing the spring) use an 1/2" drive impact gun on the large top nut
Option 2: (after compressing the spring) hold the smaller hex with a 1/4" drive socket then remove the large nut with a socket held in vise grips..

I'm not sure I understand those two options. From what I can tell from yours and John's reply, I need to by a big very offset wrench. The wrenches I've looked at won't work as the 'box' really needs to be at a right angle to the handle (to essentially look like the tool that John made). I shall have a good look around the autostore tomorrow.
Thanks again
 
OK

Best to hit first with the impact while still installed, jack beneath. 1st step. On the 02 I have accomplished the rebuild using the body weight alone. Always loosen the shock at the top first with safe support under the the control arm. My 2 cents
 
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Best to hit first with the impact while still installed, jack beneath. 1st step. On the 02 I have accomplished the rebuild using the body weight alone. Always loosen the shock at the top first with safe support under the the control arm. My 2 cents

Hi Pamp. Thanks for your reply. How does an impact wrench work? How would the piston rod be held in place?
 
No need to weld anything, just a bit of hard grafting using the file. What you need is an (old) socket, which fits in the big nut (size 27). Use a low grade so the metal is not to tough to file.

Now you need to take a file, and create two parallel surfaces. I filed it back to the size of a 27 wrench. This is the picture of the tool I made, works quite well. Depending on what shocks you have, you need either to stick an allen key or a small wrench set extender with socket 11 ( for Bilsteins) through the hole. Hold the big nut in place with the tool thus preventing the shock rod to turn and loosen the assembly.

Will cost you a socket only and maybe a file or two and manufacturing it makes for a good workout as well. Considering the cost you probably might find it in a scottish tool catalogue. Good luck.
 

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Thanks everyone for your replies. It's all been useful. Armed with this information I found a [pricey] weird socket at my local motor factors which has worked perfectly. Was the only socket of this type and just happened to be 27mm.

Still think it's odd that there's no mention of a special tool in both the manuals I looked in. Anyway, a happy ending (unless I kill myself during the re-assembly).

socket1.jpg

socket2.jpg
 
An impact wrench should be able to spin the nut off. If not, is the shaft machined for an Allen wrench? If so weld a nut on the appropriate sized socked and use a ratcheting end box wrench to turn it. The Allen wrench will fit through the nut and stop the shaft from turning while you loosen the nut.
 
Air tools, baby, air tools

This is one of the best applications for air tools -- a compressor and an impact wrench. The rapid impact of the impact wrench will spin the nut off without your having to hold the top of the piston. These days you can easily get yourself outfitted with the right sized compressor (something in the 3 hp 20 gallon range), a hose, and an impact wrench, for $250. If you work on your own car (and obviously you do since you're replacing your own struts), just do it. You won't regret it.

A common misconception about air tools is that they're for taking off incredibly tight bolts. They're not. LEVERAGE is for taking off incredibly tight bolts. Air tools are for taking off normally tight bolts incredibly quickly. Wheels, calipers, half-axle shafts (man they're great for those Allen head bolts holding on axle shafts).

Do it. You know you want to.
 
Exactly that

Do you mean not everyone has a compressor and a variety of air tools? Absolute must. I replaced my "old weezy" as I called it ('60's vintage) 15 gallon with a new DeWalt upright, Home Dept sale, very happy with this unit for the hobby shop. I also have a 27 mm X 1/2 drive deep socket with a hex on the top. Had this tool for so long I cannot remember where I got it. Same deal...11 mm socket on a 1/4 drive to hold or a long allen socket depending on the style of shock. I also can't recall when was the last time I needed to use this set up. I just back off the nut with the strut loaded by the weight of the car. I am with sfdon on this one though...coil springs are very dangerous and best left to professionals if one lacks in the tool / experience department. Dangerous for the pro's as well, be careful.
 
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I'll look into it. I've always thought air tools were for doing things quickly when time = cost. Because it's my own car and it's me working on it I never had a problem with taking my time and leisurely removing a nut at a rate of 1 nut per 10 minutes and a beer after every 10 nuts removed. I'll keep an eye out for any special deals. Perhaps a christmas present to myself.
 
Agreed with you on the beer, my friend...

...but this is one application where, without the impact wrench, it's too bloody hard to to it yourself.

If you're trafficking in beer, in the short term, you could just throw the strut assembly in the back of another car, drive it down to any service station, and give them a six-pack to whacketa-whacketa-WHEEEE the thing off with their air tools, then do it again for the other side.
 
Tools

Yeah!
Now that is the spirit! The man cave...if you build it they will come! Me, a tool junkie. Love tools and can't have enough. I can spend an hour at the Harbor Freight store although I rarely buy there. Kid at the candy store, wife at Nordstroms! If Snap-On were to open a retail store I would see a divorce soon after! Life is too short, for sure I could not live without a decent compressor. Air everything, nailers, etc. See the light. There are some things that cannot be accomplished without.. a)air impact b)sawz-all c)4 inch angle grinder... Makita is my friend. OK, perhaps a twelve step program is in order...Twelve bolts per beer! (Sorry, you are in the UK and may not recognize most of these vendors, but I hope you get my meaning) Gotta give to yourself from time to time. Me, I keep all overtime pay for the coupe and the shop.
 
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Some of us were poor at one point in the past

There was a time when some of us were poor college/graduate students and had to work on our cars in dirt parking lots without the benefit of electricity or compressed air. Hence, the cobbled together offset wrench. Yes, an impact wrench will normally spin that nut right off, but recently it failed when I was doing one of the front struts on my BMW beater. So, sometimes the hand tools are nice to have.

I've also heard that you're not suppose to put the new strut nut on with an impact wrench because you might spin the strut tube too much and damage the innards (Bilstein instructions...)

John
 
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