Replacing Torsion Bar

[craftech]

Hi,
Pleasure to join this forum. I have owned a 1984 Toyota Van for many years. I bought it new.

Recently I hit a huge pothole on the Palisades Parkway in New York and cracked the left front torsion bar.

I ordered one from a salvage yard, but I am having difficulty removing the adjusting nuts. I would like to chase the threads with a die to make it easier, but I don't know the thread size.

Does anyone know the thread size of the adjusting bolt?

Are there any things I should know besides what is in the service manual?

Thanks in advance.

John

[craftech]

Follow-up.

I wire brushed the threads really well and lubricated them with penetrating oil for days. I cannot break the locking nut loose.
Since the torsion bar broke off the adjusting bolt with the two nuts is hanging loose on the guide plate. I have two questions:

1. Is there any way to remove the adjusting bolt (with the two adjusting nuts attached) from the guide plate?

2. Is it safe to use heat?

Thanks,

John

[timsrv]

Sorry for not answering sooner (been working a lot of overtime). Bummer about breaking your van. Due to pre-loaded springs, safety can be an issue here, so whatever you do you'll need to take this into consideration. I'm having a problem visualizing what part is broken, but if it's broken in a way that has unloaded the bar (released spring tension), it will be easier/safer to work on.

Thankfully they don't salt the roads here on the west coast, so dealing with heavy corrosion under vehicles is typically not an issue here. This being the case, I have yet to run into a problem like yours. I don't know the specifics of your issue, but I'm happy to give general advise. When things become hopelessly stuck, in extreme cases you may need to resort to extreme measures. These measures include using tools such as cut-off wheels, grinders, and cutting torches. When these tools come out, typically parts will be sacrificed. As a general rule you can safely put moderate heat on mild steel. Enough to make it slightly glow is usually okay, and this should not permanently weaken it. However, you should never do this while it's under pressure (spring pressure or other such stress). In addition, attention needs to be given to surrounding areas. You'll need to consider proximity to wires & rubber parts (parts that may be flammable and/or damaged by heat). Undercoating can also be flammable, so there's that too. The fuel tank is close here as well, so there's that hazard to consider. Heat should never be applied to spring steel (like torsion bars) if they are to be re-used, and especially not while under any kind of load. Aside from spring dangers (unpredictable/sudden release), if you're inexperienced, the use of these tools can also be dangerous (especially under a vehicle). So if you don't have access and/or experience using them. it may be time to take the van to a shop that does this type of work. You should also decide ahead of time what parts need to be sacrificed and find replacements before you cut. Good luck. Tim

[craftech]

Thanks for the reply Timsrv. I truly appreciate it. In fact I have removed the parts already. The torsion bar broke near the forward end right at the spline so it came out quite easily.
It was the dangling adjusting bolt with the cam and the two locknuts still attached that I was having trouble removing. But I had already managed to remove it and now know the sizes and several other tips, so I want to list the steps for anyone else who runs into the same or a similar situation.

1. The torsion bar adjusting bolt is 12mm x 1.25 so clean the threads with a wire brush or wire brush attachment for a drill first, then clean (chase) the threads with a 12mm x 1.25
die if you have one. Since the die handle doesn't have room to turn use a 1" deep 1/2 inch socket to drive the die. When the adjusting bolt starts bottoming out in the socket, remove
the 1/2" ratchet handle and turn the socket with the die in it by hand. The 12mm adjusting bolt will just fit through the 1/2" square drive end of the socket.

2. Use low heat at the juncture of the two nuts until you can turn the locknut. The nuts are 22mm, but a 7/8 wrench will do as long as you don't have to force it to turn which might strip
the corners of the hex nut. I found that an oxygen sensor socket that I had was 7/8 and worked quite well. With the slit down the side of the socket it made it easy to see what was going on
as well. In my case since there was no tension I had to support the bolt assembly by using an open end wrench on the two flat sides of the adjusting cam while I turned the locknut to break it loose.

3. With the locknut removed I threaded it again up to the adjusting nut and repeated step 2.

4. The cam is supposed to slide off, but it was rusted in place so I threaded it up to the cam, used a finishing nail to clean inside the cam around the threads, applied heat and "unscrewed it" off.

5. Then I chased the threads of the adjusting bolt all the way up with the 12mm x 1.25 die.

6. If the bolt has to be replaced you have to remove the middle seat, remove the carpet, remove the luan wooden floor panel, and near the battery compartment you will see a plastic (rubber)
plug around 1 1/4 inch diameter. Remove the plug and you will see the head of the adjusting bolt which you can then pull right up through the floor. With the bolt removed you can slide the upper pivoting support cam sideways out of it's compartment underneath.

John

[craftech]

I have an installation question on the torsion bar (left side) If you recall, the torsion bar broke and I got one from an auto salvage (off a 1985 Van). I measured Distance A before I disassembled the dangling bolt, anchor arm, nuts, and cam. I would like to use that measurement to install it, but the directions confuse me. It says:

(f)Make sure that the upper arm is positioned horizontally.

Assuming by "upper arm" they mean the upper control arm in the front, does that mean jack up the lower control arm until the vehicle starts to lift off the jack stand? That brings the upper control arm roughly horizontal.

The diagram shows a 40 degree angle for the anchor arm, but there is no reference to it in the instructions. How is that accomplished? I am not following the procedure to restore the salvage yard torsion bar to where the original one was before it broke. As I mentioned, I have distance A.

John

[timsrv]

I agree the book is a little vague here. In reading yours I don't think they are talking about the a-arm. I think they're talking about the anchor arm. When they say horizontal, I don't think they mean exactly. I think they are saying somewhere in the range as shown in the figure (as to allow the nut to be started on the bolt). Out of curiosity I checked in my 89 manual and see they've omitted the statement "(f) Make sure the upper arm is positioned horizontally". They replaced it with "(e) install the anchor arm to the torsion bar as shown in the illustration (f) Finger tighten the adjusting nut and measure the bolt end protrusion. Bolt end protrusion: About 40 mm (1.57 in.) If bolt end protrusion is not as specified, reinstall the anchor arm in the correct angle.

The rest of the procedure is pretty much the same in both books. Tim

[craftech]

I agree the book is a little vague here. In reading yours I don't think they are talking about the a-arm. I think they're talking about the anchor arm. When they say horizontal, I don't think they mean exactly. I think they are saying somewhere in the range as shown in the figure (as to allow the nut to be started on the bolt). Out of curiosity I checked in my 89 manual and see they've omitted the statement "(f) Make sure the upper arm is positioned horizontally". They replaced it with "(e) install the anchor arm to the torsion bar as shown in the illustration (f) Finger tighten the adjusting nut and measure the bolt end protrusion. Bolt end protrusion: About 40 mm (1.57 in.) If bolt end protrusion is not as specified, reinstall the anchor arm in the correct angle.

The rest of the procedure is pretty much the same in both books. Tim

OK, that makes more sense. So if I just let the front suspension dangle and install the anchor arm to the torsion bar roughly horizontal and then adjust the nut to what "A" was before, I should be good it seems. Is that right?

Thanks as always Tim.

Regards,

John

[timsrv]

That's my take as well. I've replaced torsions before, but I didn't use the manual (I just marked things then put back the same way as they were before). I did however use the manual for specs on ride height. If for some reason you're "out of range" then you could always go back and reposition splines as required, then try again. Tim

[craftech]

That's my take as well. I've replaced torsions before, but I didn't use the manual (I just marked things then put back the same way as they were before). I did however use the manual for specs on ride height. If for some reason you're "out of range" then you could always go back and reposition splines as required, then try again. Tim

That's what I would have done if it didn't snap and fall after I hit one of the Northeast's now permanent pot holes. Hopefully the ride height will be OK. I'll simply match it to the right side.

Thanks for taking the time on a Saturday to help me out. I really appreciate that Tim.

Regards,

John

[craftech]

Follow-up:

It seems that installing the anchor arm at a 40 degree angle rather than horizontally works. In terms of "measurement A", it is irrelevant since the final measurement was no where near the original amount.

I used the non-scientific method of sticking my fingers between the top of the tire and the wheel well. Three fingers on the right side. so I adjusted the torsion bar until I had three fingers on the left side.

It work, so thanks for all the help.

Regards,

John

[timsrv]

Thanks for the follow-up. I was thinking horizontal didn't make sense (how can you adjust if it's already maxed out?). At least they took that part out of the later manuals. Tim

[craftech]

Thanks for the follow-up. I was thinking horizontal didn't make sense (how can you adjust if it's already maxed out?). At least they took that part out of the later manuals. Tim

Makes sense Tim. Your manual indicates a "bolt end protrusion" figure. After completeing this, it would seem that it would vary with where you started out so how can they give you that figure?? Right now, mine is way past 40mm.

John

[gushaman]

A trick for locking nuts: two wrenches, one on each nut. Making sure that the wrenches are in different posiions, say at 5 and 7 if it were a clock, you can squeze the wrenches together and it will loosen the lock nut. I do it on chains and hydraulics all the time

[craftech]

A trick for locking nuts: two wrenches, one on each nut. Making sure that the wrenches are in different posiions, say at 5 and 7 if it were a clock, you can squeze the wrenches together and it will loosen the lock nut. I do it on chains and hydraulics all the time

Thanks Gushaman. Much appreciated.

John

[MyToy]

Need some help with my torsion bar.

Decided to adjust them to the stated spec in the manual. Really a no brainer..............But

On the driver side torsion bar adjustment, I removed the locking nut and then lowered the adjusting nut so I could clean and lubricate the threads above the nut also. So I brought the nut down to about a half an inch to the end of the bolt. Cleaned an lubricated the threads. When I went to advance the adjusting nut back up it would only turn 2 times then fall back to where it was. Examining this closer it seems that the adjust bolt threads may be stripped at that point. I was somewhat scared to remove the bolt totally to inspect should the torsion bar arm spring of and wack me and the van chassie and I would never be able to get it back on.

Can anyone tell me if the bolts length is long enough to reach the anchor Arm so I can just replace the bolt and nuts and use them to bring the anchor arm back to its correct position?

That being said, if it does spring off, how to you get the torsion arm back on the bolt should the torsion spring tension be so great it cannot be put back by hand?

I am hoping the bolt can be long enough to reach the anchor arm and just use the nut to bring it back up to spec.

Any thoughts anyone????

MyToy

[Jan-Willem]

Couldn’t you just use both nuts to move them up the thread? Like, rotate the top one 1/3 turn, then rotate the bottom one 1/3 turn. Then you can use twice the treads, maybe you can get past the bad section of threads, maybe it is just rusted on the end protruding below its normal position.
And the van is lifted with the front wheels hanging down I hope, otherwise you are fighting the weight of the van.

[MyToy]

Thanks, Jan for the come back.

I did consider that but where the nuts are currently positioned both are slipping. As I said, they are almost off the end of the bolt. I am afraid that if the anchor arm is still spring-loaded with the bolts all the way to the end of the bolt it will pop the two nuts off with no help from me.
If I knew I could get the anchor arm back on the adj bolt I would take the nuts off and let it naturally let go. But I don't know that.

Have you ever taken the anchor arm off Jan?

Mytoy

[Jan-Willem]

I removed the nuts and that lever bit, yes. Not the bolt, i have no idea how it comes out. But i do nott dare to advise you on that, as I have no idea if the parts on my van are original. The bolts on mine are about 18.5cm long (7 1/4 inch), but they look surprisingly healthy, considering the rust on other components. And i don’t know if the torsion bar can slot in, multiple ways. I marked mine, took it out, and put it back the same way. But yeah, on mine, with my torsion bar, with the adjustment bolts on my van, there wasn’t any tension on the adjusting nuts, when I loosened it to the end of the bolt, only the springinesses of the (worn) suspension business. I could easily move the lever away from the nut, when pushing the wheel down.

[MyToy]

Wow, that is great news Jan. I never thought of pushing the associated from wheel down to receive even more spring load. Dhhhhh.

Yeah, my bolt is the same.

OK, so I will just have someone push the wheel down and I will drop the nuts and replace the bolts and nuts at the same time. Piece of cake.

Thanks again Jan, big help.


Mytoy

[Jan-Willem]

LOL i immediately crawled under my van, because to me that job didn’t seem easy at all, that is getting the bolt out. Funny how people can get stuck at different parts of the same task. I could not figure out how the bolt could ever get out of that floor support. But now I see the rubber plug above it. From the top it is hidden by the carpet of course…