Friday, November 5, 2010

torsion bars, tools and the trunk lid

It seemed logical to re-install the trunk lid next, the rational being that it would be much easier to figure out the alignment if I could access the lid from underneath - in other words before I put the rear axle and suspension back on the car. Of course it also helps that the gas tank is absent from that area too. It would also be easier to install the lid, I presumed, while the car was still raised up on stands. I've never had a go at aligning body panels or doors before but I've read many times that it can be a tough and tedious process - so I was well up for anything that would make it easier.

I started by bolting the trunk hinges back in - since I never got round to having these pieces media blasted, lining up the bolts and washers with the marks on the hinges was really easy. Ford originally painted these cars with the hinges in place, so the area of the hinge covered by the washer was bare metal.

With both hinges secured, the next item is the pair of torsion bars that provide the spring for the trunk lid to open. My trunk lid always flew up like a Bat Out Of Hell whenever I popped the latch, and the torsion bars were already set to minimum adjustment, so long term I may do something different in this area. For now though, torsion bars it is...but, hey, steady on...this is a tough job. I think it took me about two seconds to realize I couldn't possibly perform the installation with my bare hands...not a chance! In the days gone by when I've been faced with this kind of problem I usually scratch around the garage and find a tool that "might help" and then carry on. However, this approach has led me to damage stuff I've been working on, break tools and even injure myself on enough occasions that I finally abandonerd it. These days I figure out exactly what tool I need, and then acquire it before making a balls up.

My first port of call when looking for help is usually the Vintage Mustang Forum. I've always found helpful advice there, even if you often have to weed out some rather odd suggestions on the way. What I found this time was a gazillion stories about how tough it can be to reinsert (or adjust) trunk lid torsion bars...and several warnings about the potential for loosing fingers...or worse. Strangely I don't remember anything much happening when I removed the bars, which I did by unbolting the hinges and letting them "drop" out. Anyway, I considered putting the trunk lid back on the car without the torsion bars - why not, it all has to come off again later anyway...but I didn't get this far with my project by taking the easy option, so I plumped instead for some more research.

The Ford 1968 Shop Manual describes a special tool, part # T64K-44890-B for this task on page 17-91, and gives a rather vague picture. A bit more searching led me to the schematic below, which I also found on either VMF or one of the Cougar forums. A reproduction of this tool is available on Ebay or here from West Coast Classic Cougar for about fifteen dollars.

Click the picture for a much larger (readable) version
I considered buying the WCCC tool, but I was really too impatient to wait around for delivery, so I decided to have a go a making the tool myself. I didn't have any flat bar lying around, so I started off with a piece of one inch angle that came from an old bed frame. The key to this tool is getting the distance between the hole and the slot spot on. I made it about an eighth of an inch oversize the first time (I misread the diagram and was working from hole centers!), but it is much easier to elongate the slot and trim an eighth off the end of the tool than it would be the other way round. I also found that the 1/4 inch hole shown in the diagram was too small for my torsion bars, so I drilled it out to 5/16ths. The final step was to chop out a V shape in the extraneous side of the angle with my new four inch cutting wheel, and bend it in the vise (note: the reason for the bend is that the tool has to be short in order to fit in the space available, yet strong enough to provide sufficient leverage).

Even with my new tool however, it was hardly plain sailing from this point on. I had a number of fruitless attempts to get the first bar installed while the bar either popped out of the tool (bad!) or out of the hinge at the other side (also bad). I was being careful, so I never came close to losing a finger, but the noise the torsion bar made when it smacked against the inside of the trunk was incredible. I even managed to generate a spark on one occasion. Eventually I secured the upper end of the first bar at the driver side by wrapping some 14 gauge copper wire around the bar and the hinge and then tying the hinge in the "fully up" position with some #4 nylon cord. I then used my new tool to twist the other end of the bar sufficiently to clip it into position at the passenger side. Phew! I should have taken more pictures of this, but I was a nervous wreck by the time I was done. I repeated the process for the second spring, securing it at the passenger side and rotating the other end as before and I got it in the slot first time. (note: essentially the tool is being used to twist a 1/4 inch diameter steel rod, and that takes a significant amount of force...of course the usual disclaimer applies to everything on this site, but seriously, don't try this at home kids..unless you really do know what you're doing).

Here's the big picture. Was it worth all the trouble, given that this all has to come out again later for a refurb? Well, I think so. It's all valuable experience, and, although I managed to make a couple of light scratches on the inside of the trunk, I did it all without doing any real damage to the car or myself, which is of course a good thing.

Next up was the trunk latch and lock barrel. I cleaned and oiled up these parts when I originally removed them, so they were in great shape and went straight back in with no fuss. I put the bolts in pretty loosely to start with.

The trunk lid has not yet had the attention it deserves, so there were some rather obvious bare patches in the rust to tell me where to insert the clip nuts.

It was not easy to hold the lid and bolt it to the hinges on my own. I used a few rolled up dust sheets to provide a kind of pad on which I could lean the lid while I got the first bolts in and then I had my first try at closing the lid...and it was nowhere near. Not even close. It would only close to within about six inches from the back of the car before the rear edge caught on something.

This led to a lot of back-and-forth with the wrench and the lid until I got it to at least close correctly...but now it was too high at the more back and forth...and so on...and eventually I got it to close, but now the lid was skewed so the gap at the left rear was massive and it was virtually touching the quarter panel at the diagonally opposite corner. I started to wonder why I ever took the hinges off. It was at this point that I gently slackened off all four hinge bolts, maneuvered the lid into prime position from the outside, and tied it closed with some nylon cord. Then I wedged some paint stir sticks in the side gaps, climbed into the trunk from underneath, and tightened down the hinge bolts.

The driver side front corner is still a little bit high, but it is certainly good enough for now...a blind man would be happy to see it! Finally I reinstalled the latch striker, and, also from inside the trunk, aligned it with the latch and tightened up all the bolts. Now, on with the suspension and rear axle...


  1. Wow, thanks for the detailed info on the deck lid hinges. You've made me feel all guilty now for having not removed mine to protect the metal underneath (I had just blasted the trunk area with hinges in place). I might make up one of those tools and do my hinges up right. Good job getting your lid realigned.

  2. Thanks Alex. I know I don't need to say this, but if you do go this route, it pays to be really careful. I would recommend making (or buying) the tool first and using it to remove the torsion bars before you unbolt the hinges...the tension on the bars is huge. Good Luck!


  4. The most helpful advice I've had yet on trunk torsion bars - Thanks. Do you have a photo or sketch of how the tool fits on to the rods? I should be able to work it out but it would help. My spray painter removed the hinges & rods when he sprayed the car & I'm having a pretty hard time getting them right.

  5. Hey, thanks for your comments ^^. Unfortunately I don't have that particular shot - in fact I have very few pics apart from the ones above as my usual trigger-happy nature was suppressed by the serious business of getting the bars twisted up tight without losing a finger. Good luck!

  6. Really appreciate you writing this up! Just about to take the trunk lid off my 65 coupe and was really concerned about the springs. Having fabricated the tool, taking them off was "easy". Like you say still have to be careful but it's perfectly safe and controlled with the right tool. Thanks again!

    1. Thanks for your comments...happy I could be of some help to someone...more than enough people that have helped me :)

  7. I just discovered your blog searching for the trunk torsion rod tool and have become a follower... love the early generation ('65-'70) Mustangs! BTW the hole sizes noted on the tool diagram are DIAMETERS not radius..... Keep up the good work!

  8. Brother... I feel your pain and total anxiety when doing these torsion bars.. I'm still wondering how not to knock any paint off while putting them on. Yes... that is the most complete way to do the trunk lid is get that gas tank out. I didn't and now have to redo it the right way. Thanks for posting this as it helps a lot...