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Paul Mossberg.
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June 7, 2010 at 8:39 am #233024
Bled and adjusted the brakes Sunday instead of attending the “Original British Car” meet & greet 2 hours away at Lilypons Water Gardens. T-showers in the forecast scotched that ride, plus I was dealing with about an inch of brake pedal. It seemed to be getting just a tad worse this past week during my daily jaunts in support of British Car Week. Figured it could use some attention.
So I looked at the linings; all good–1/8-inch or better. Got familiar with the adjuster stars, and discovered that the left front wheel (driver’s side) was loose on the backing plate.
To be clear: the bearings are fine. But the three bolts holding the backing plate to the control arm had backed out, so the brake mechanism could shift about a quarter inch.
Figured that might be why it’s been locking up on hard braking.
Took off the hub, inspected the outer bearing (fine), pulled the backing plate bolts and re-bent the lock washers, dabbed a bit of lock tite on the threads and tightened them all back good, with the plate as far forward as I could get it. (oops, I think).
Added some bearing grease and re-assembled. Bled, got 3 inches of pedal back and some action on the rear drums, which apparently was lacking previously. Yahoo! Took her for a test spin, revved her up and discovered that she still locks up that left front wheel.
Stops a lot better, and mostly straight (until that front wheel locks, then she skids a bit to the right).
It’s better enough that I feel way more confident driving her to work today than I did last week. But I wonder if anyone has any experience with/advice on this issue.
My theories are as follows:
1. the backing plate shifting has reshaped the brake pads on that wheel; in time this problem will diminish as the pads wear in again.
2. I should have tightened the backing plate on the other end of its travel, as the forces in play during a hard stop going forward will tend to set the plate to the rear of the car, not the front, as I had erroneously envisioned (see “oops,” above).
3. I am a fool, endangering myself and others, and should have overhauled the front brakes completely yesterday as any half-competent mechanic would have advised. And also cleaned and re-packed all the bearings. And while I’m at it installed the bloody adjustable beam. Only thing to do now is take it apart and do it right. And never drive it again ’till that’s all done.
edsnova 40336.3646759259 June 7, 2010 at 10:26 am #241593Ed, All three theories have some credibility if you leave out the ”fool” part.
Another problem I ran in to was that the flexible hoses were blocked with gummed up brake fluid. Enough fluid would pass to at least partially apply the brakes but the return springs could not pull the shoes away from the drums and the brakes would drag just enough to get hot. I replaced the hoses and that solved the problem. Is it possible that you may have a problem on the right side which is causing the left side brakes to do most of the work?
Having said all that, a complete rebuild would be the best route but it would be nice to find out the cause of the lock up under hard braking.
June 7, 2010 at 11:38 am #241594I second all of the above.
In particular the brake line repplacement. They may look OK from the outside, but could be rotting away from within.
Paul Mossberg
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica RoadsterIf you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)
June 7, 2010 at 3:27 pm #241595Hi Guys
Just one note on Grabby brakes after many theories have been proven false.
ONCE A BRAKE SHOE HAS GOTTON GREASE OR BRAKE FLUID ON IT IT WILL BE TROUBLE. Most commonly grabbing or locking up. Drum brakes are “self activating” which means the forward rotation of the drum puts pressure on pivot pin causing the shoe to pivot toward the drum and give you added braking. If the coefficient of friction has changed due to contamination or other problems it screws up this feature of drum bakes and makes it a ‘PAIN’.
Disc brakes do not have self activation and require more pressure to give the same amount of braking as drums. In our “nose light” tdreplicas I believe we have too much braking up front and the less efficient disc brakes are a good idea. The kits are so cheap now that it’s hardly worth rebuilding your drum brakes. I dn’t know how good the kits are, however. I think I’ll buy all the original vw parts at a junkyard or on craigslist and rebuild them. Anybody out there have any comments on the various kits?
Chuck
June 7, 2010 at 3:58 pm #241596I’m hearing what you all are putting down, I’ve had similar problems with locking under hard braking and I’m told its something about wieght and that being the wieghted side. I’m definitly changing my lines, I’ve already rebuilt brakes. but I really don’t use the brakes for much more than stopping anyways.
June 7, 2010 at 9:20 pm #241597Thanks for the input, gents. I think the brake line replacement is in order anyway–they’re certainly old. In addition, the bleeder screw on the grabby brake behaved strangely, dribbling a bit and not squirting like the others. Could be clogged, which means there could be cloggy crap in there behind it, which means, I guess, that similar particulate matter might just be in that wheel cylinder too.
Rich–the disc brake conversion was on my to-do list when I thought I was gonna load 800 lbs of batteries in the car, and fell off (the list, I mean, not the batteries) when I decided to bag that particular fantasy, at least for the time being.
Happy to report I made it home from work safely today (and that’s eight days straight of driving Bridget somewhere on public roads). I will drive her short distances for the next couple weeks and test for grab-lock. If it doesn’t subside I’ll tear back into the job before doing any more long trips.
Even with the trouble, she does stop a hell of a lot surer than she did before, so there’s progress at least.
June 7, 2010 at 11:40 pm #241598Having watched in my rear view mirror as Ed’s brakes locked up…I’m glad to hear they are getting straightened out.
Ya know, brakes or not, you guys that can simply drive your TDs around are really starting to tick me off.
I’ve still not been able to set aside a weekend to pull my motor. So I still don’t know what’s going on inside.
Paul Mossberg
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica RoadsterIf you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)
June 8, 2010 at 7:25 am #241599Sorry for your troubles, Paul. On the bright side, though, you probably have more miles/days on road with your TD than anyone else on the board. Maybe anyone else on the Earth. You’ll be back.
June 8, 2010 at 9:20 am #241600Not even close.
The old New Jersey Replicar Club had two members living in north-eastern Pennsylvania that had front engined TD’s, FiberFabs I think, one red, the other a light, creamy yellow, each with a matching trailer.
These two guys and their wives had covered the entire contintental US in their TDs, including several cross country vacations. They had tens of thousands of miles under their belts.
My favorite story was their trip through Death Valley, in open top TD replicas. They kept coolers of ice and water in the cars, everybopdy wore some sort of wool (yes WOOL) cap, that they repeatedly soaked in the ice water. Kept them cool throughout the trip. Heck, people crossed Death Valley on horseback, why not with horsepower? at various scenic stops, “regular” vacationers would jump out of their A/Ced cars, take a quick photo and jump back in. Our friends were able to really relax and enjoy the vistas.
Both have now passed. They were great guys.
I’m way off topic and have rambled on too long.
Back to our regularly scheduled thread…..
PMOSSBERG40337.61875
Paul Mossberg
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica RoadsterIf you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)
June 8, 2010 at 6:18 pm #241601Paul,
Cool story – love to hear more about those folks some time – hopefully I will
do something like that when I stop working.
June 8, 2010 at 10:08 pm #241602I’m pretty sure one of the old kit car mags did an article on them. I will have to dig through my archives.
Paul Mossberg
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica RoadsterIf you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)
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