Bonnet Release Cable Broken! (TR4-TR6)
by Ken Streeter, with input from
Triumph Service Bulletins, 6-Pack, TRF,
Jamie Barnhardt, Steve Benelisha, Jim Bosley, Robert Carley, Shane Ingate, Larry Miceli, Robert Shaw,
and others from the triumphs mailing list.
A broken bonnet release cable on the TR4-TR6 can cause no end of difficulty in getting the hood up to fix the problem! This is a common problem in North American TRs with LHD steering, since the hood release cable is quite long and cumbersome, having been intended to be on the right side of the car.
However, before you dismantle anything, ask someone to push down on the bonnet near the latch area; this will remove any “reload” on the mechanism which may be you problem. Be careful and be sure to press the bonnet as close to the edge as possible to avoid the common dent in this area. If this works for you, the problem may be improper bump adjustment, over-adjustment of the latch pain, or, most frequently, lack of latch lubrication.
If simply having somebody push on the bonnet near the latch while operating it doesn’t work, the summer 1994 issue of the 6-Pack (TR-6 club) newsletter published a reprint of a Triumph Technical Service Bulletin dealing with broken hood releases. In summary, you will need to remove the glove box, to gain access to one of the holes through the firewall. (There are plenty of likely holes for the heater control, choke cable, etc.) You may want to also remove some of the heater hot air hoses to get more room under the dash. With a long screw driver, and lots of patience, you should then be able to reach and activate the lock release mechanism. It is somewhat difficult to see what you are doing, both when you are disassembling the under dash components, and then when you are trying to pry the hood latch open with the screwdriver. You have to visualize the operation of the hood latch i.e., in which direction it pulls to free the hood catch.
You also have to be careful with the screwdriver or pry bar, as you are close to the battery connection – if you hit the battery cable, you’ll get quite a spark! So, be very careful when you are poking around the hood latch from through the hole in the firewall while lying on your back in extreme discomfort.
If your cable isn’t actually broken, but doesn’t seem to work, Larry Miceli suggests that you can remove the nut that holds the cable onto the bulkhead fitting so the whole thing (inner and outer cable) moves. Then when it “stretches” pull a little more. This will work for you if what has happened is that the pinch fitting holding the outer sheath has come lose. If you can pull a little more the latch WILL pop open. Larry had this problem on his old ’74 TR6 until he replaced the .30 cent clip.
Another technique has been suggested by Robert Shaw, who had this problem a few years ago, and took the car to his mechanic. The mechanic put the car on a lube rack and with a long extension and a 1/2 socket reached right up and presto unbolted the hinges at the front of the bonnet. It took him about 20 minutes and it was opened.
Yet another idea is from Jim Bosley, who put the front end of the car up on jackstands and then using a broom handle cat to the proper length, was able to reach the latch from below the engine and right front tire.
An ounce of prevention…
A smart trick to prevent future problems is recommended by TRF: attach a wire to the release lever, and route it so you can pull it to open the latch from below or from in the cockpit. There are a number of convenient holes in the TR6 bodywork to stuff the cable through, and it will be *extremely* helpful if your primary cable ever breaks, which seems to happen at the worst of times! It will be easier to use if you put a loop or a T-handle at the end to pull on.