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Universal joint let go

Griz

Jedi Hopeful
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Here's what happens when the front universal joint lets go at 60 mph. Still not sure how that happened, but I suspect that one of the cup spring clips was not properly seated in its groove allowing the bearing cup to be thrown out. Destroyed the fiberglass transmission cover and carpet. It's a little un-nerving to see things disintegrating about 3" from your right hip while you're trying to get stopped! I'm lucky in that I can get a new carpet replacement, and the fiberglass cover is also available for a (large) price, but does anyone happen to have a used spare cover (center shift for a BJ7) that they would part with?

Thanks,
Griz
 
Steering columns to spear us in the event of a frontal collision; windshield frames against which we can crack our heads; no crumple zones, no rollover or side-intrusion protection, etc: Things I try not to think about while merrily cruising along!

There's no question but that our cars are inherently dangerous and little we can do to minimize many risks but it is not difficult to put a protective hoop around the driveshaft under the removable transmission tunnel. These are required in vintage racing and on the Courier I used 1-1/2" x 1/4" steel, bent it into an omega shape (inverted U with big seraphs) to conform to the inner shape of the tunnel and through-bolted it to longitudinal members.
 
... Still not sure how that happened, but I suspect that one of the cup spring clips was not properly seated in its groove allowing the bearing cup to be thrown out...

Was the U-joint recently installed? Certainly something to check when replacing them.
 
Griz,
I'm sorry to hear about this. Your brand new, beautiful restoration hurt before it's even broken in. As you know I'm just a few weeks behind you with mine. My first thought was answered by Michael. I'll add an omega to my alpha project.
Dale
 
Glad to learn you were not harmed by flying debris. Would it be possible to repair the damaged tunnel? It's fiberglass and could be built out again on a form. The big box stores generally have what's needed to do the job. I recently repaired mine with good results. GONZO
 
Michael,
Could the protective hoop be molded into the fiberglass tunnel cover? Or is it best to have a gap between the cover and the hoop? Maybe there are specs already in place for racing?
 
Dale--

I don't think any race group specifies how and from what material the hoop is to be made. For example, Vintage Racer Group's says: "3.2.6.6. Drive shaft: It is recommended that all front-engine, rear-wheel-drive cars have a 360o safety hoop enclosing the drive shaft, to protect the driver in the event of u-joint failure."

If a car's driveshaft has two yokes--as does that in an Austin-Healey--then since either U joint can fail you really would want two hoops as one in the middle might not capture a flailing driveshaft. If a driveshaft connects to the transmission via a sliding yoke--as is the case with the MG transmissions in both the Elvas and the Ford transmission in the Ginetta--one needs only to be concerned with containing it where it couples to the differential.

Below are pictures showing the hoops I fashioned out of steel strapping for the Courier and the box sections that are parts of the Ginetta's construction. Notwithstanding my statement in the preceding paragraph, in the Courier I put in two hoops with U-shaped strapping above the driveshaft and flat strapping below, all bolted into angles welded up to the fore and aft frame rails, the front one serving to make the sheet metal tunnel stiffer and that is the one pictured. The rear hoop is much the same and captures the driveshaft at the rear cockpit bulkhead, close to its point of attachment to the differential flange. Both setups provide 360o protection.

Whether you choose to entirely surround the driveshaft 360 degrees or simply have a hoop that goes over the shaft, laminating it into the FG transmission tunnel sounds like an unnecessary complication and, depending upon attachment points in the longitudinal frame members, might make it very difficult if not impossible to pull the tunnel without removing both seats and other interior panels. Rather, I would suggest that you fashion hoops that would fit under and close to the tunnel as I did with the Courier and depending upon how you do things this might make installing/removing the tunnel easier.
 

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Thanks Michael. I have a better understanding now. The potential major damage to the car and risk to the driver is from the drive shaft not necessarily the small bits from the U joint. A guard separate from the tunnel cover makes sense.
 
Fortunately for me the metal portion of the driveshaft tunnel contained the flailing driveshaft and sustained little or no damage. I have a line on a used fiberglass tunnel, but if it doesn't pan out I probably will repair my old one. An added containment loop definitely is a good idea.

Griz
 
Well it ain't pretty, but it will be functional. I've been able to repair my fiberglass transmission cover. One additional modification I will be making is to add a rectangular hole and rubber plug (same size/shape as tranny oil check hole) over the speedometer right angle drive unit. My speedo quit working several weeks ago and I had to remove the drive and make repairs. It was a royal pain in the a** with the transmission cover in place.

Griz
 
IMG_2737.jpgAlmost too ugly for pictures! Had to form sheet metal to replace destroyed portions of transmission cover, then I fiberglassed over the metal.

Griz
 
Great save on the trans cover. Love the patchwork...a perfect Frankenstein. Thanks for sharing. GONZO.
 
That looks good. At least as good as the original and much stronger. Carpet pretties everything up anyway.
 
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