Anglefire Posted February 13, 2019 Report Share Posted February 13, 2019 I’m “struggling “ to get the rear brakes adjusted to be snug to the drums and hence get a nice handbrake as you rotate the drum it seems to have high and low spots - not that you can feel them under braking. So I have decided to change the drums and possibly shoes. But the question is where is the best place to get them from ( cost is not a major issue as none of the places I’ve looked are exactly expensive) - the ones I fitted after I got the car came from eBay. Though most of the rest of the brakes came from David manners from memory. Link to comment Share on other sites More sharing options...
johny Posted February 13, 2019 Report Share Posted February 13, 2019 I had this on my Vitesse and the replacement drums for it are much more expensive. However I believe cast iron can distort after being cast so should be left for sometime before machining but in many cases this isnt done so after installing your new drums they can later become oval again. In the end I got my original items turned in a lathe which has brought about a great improvement even though the machine shop found it difficult to do without the correct mandrel. Probably something suitable could be made using part of an old halfshaft so that the drum could be reverse mounted and then machined perfectly concentric...... Link to comment Share on other sites More sharing options...
Anglefire Posted February 13, 2019 Author Report Share Posted February 13, 2019 The old drums have long since been dumped! though the current ones look steel rather than cast. Though that is probably just because they are shiney! Link to comment Share on other sites More sharing options...
poppyman Posted February 13, 2019 Report Share Posted February 13, 2019 How long have the shoes been fitted Mark? Have they bedded in yet? Also manual or self adjusters? Tony. Link to comment Share on other sites More sharing options...
Anglefire Posted February 13, 2019 Author Report Share Posted February 13, 2019 They have been in probably 18months to 2 years. Not a massive number of miles though and the brakes were terrible for a while - mot brake test was marginal. Manual adjusters. Seem to be too loose on one click and too tight (in spots anyway) next click up! And I’ve used a copper hammer to centralise the shoes too. I suspect the run out is actually tiny - but enough to cause this issue. My dad has a lathe and if I could think of a way of mounting the drums on it without spending more than the cost of a set of drums I would see what they looked like! Link to comment Share on other sites More sharing options...
johny Posted February 13, 2019 Report Share Posted February 13, 2019 Fraid the fact that a new set have gone out of round seems to back up my theory Mark. I cant believe theres many manufacturers of the replacement drums now so all available are likely to come from the same source and be prone to distortion. I went to a local machine shop who had a big lathe and they did the pair for a very reasonable 20quid (reckon they underestimated the work). However they couldnt guarantee the results as they had to use the centre hole in the drum as the datum for centering the drum in the chuck. Apparently they didnt have to skim a lot of metal off but it had been enough to cause the intermittent rubbing..... 1 Link to comment Share on other sites More sharing options...
Anglefire Posted February 13, 2019 Author Report Share Posted February 13, 2019 I’m not convinced they weren’t out of round from new! Hence the desire to get the best ones. But if they are all bad I’ll have to think again. Link to comment Share on other sites More sharing options...
johny Posted February 13, 2019 Report Share Posted February 13, 2019 Perhaps we'll get some other feedback from someone..... I believe back in the day there were lots of places capable of doing this machining but now its cheaper to replace than repair so if theres any left theyre difficult to find and probably not close by..... Link to comment Share on other sites More sharing options...
Pete Lewis Posted February 14, 2019 Report Share Posted February 14, 2019 things happen very frequently trailing shoes fitted upside down ( square hole must be at the bottom) opposite to the leading shoe handbrake hole the hub flange is the cause of the runout , due to years of wheels on wheels off etc.or heavy handed attempts to remove the hub flange the drum retaining screws are proud of the drum face and fitting/tightening the wheel distorts the drum due to contact Pete Link to comment Share on other sites More sharing options...
johny Posted February 14, 2019 Report Share Posted February 14, 2019 Ive wondered if the drum cant be bolted the reverse way onto the hub flange (it should still centre correctly) and then rig up an electric hand drill with grind stone (possibly on a pillar assembly mounted horizontally?) so that while an assistance spins the halfshaft steadily by hand the drill can be moved in slowly to surface grind the braking surface..... Got to be worth a go😎 Link to comment Share on other sites More sharing options...
poppyman Posted February 14, 2019 Report Share Posted February 14, 2019 It might be worth trying to find a pair of old second hand drums Mark? Even if they have a "lip" it's easily sorted. Tony Link to comment Share on other sites More sharing options...
johny Posted February 14, 2019 Report Share Posted February 14, 2019 trouble is you wont know if theyre out of round as well until youve put em on the car and then its a bit difficult to ask for your money back...... Link to comment Share on other sites More sharing options...
poppyman Posted February 14, 2019 Report Share Posted February 14, 2019 43 minutes ago, johny said: trouble is you wont know if theyre out of round as well until youve put em on the car and then its a bit difficult to ask for your money back...... I did think of that, but was thinking more about quality than anything else. Tony. Link to comment Share on other sites More sharing options...
johny Posted February 14, 2019 Report Share Posted February 14, 2019 my original drums have definitely benefitted from machining so it seems new and old all have the potential to be or go out of round..... Link to comment Share on other sites More sharing options...
poppyman Posted February 14, 2019 Report Share Posted February 14, 2019 17 hours ago, Anglefire said: - mot brake test was marginal. With the brake test only marginal, have the brakes been adjusted correctly? ie with both handbrake cables disconnected, and do the cylinders slide on the back plate? If so the brakes should still work ok, It's just puzzelling me a bit...... Tony. 1 Link to comment Share on other sites More sharing options...
Pete Lewis Posted February 14, 2019 Report Share Posted February 14, 2019 i remember the father in law trying to machine some cortina drums on a lathe with bed height suitable raised with some fence post and a highly misaligned tail stock managed to turn a wonkey drum into something which resembled montezuma's revenge would have been proud of steel naive cast rim orrible ford things . tolerance , cant remember but our truck drums think runout was 0.008" and these where 14/18" dia with 8" wide swept surface so getting it on a stool with a vice clamped up drill base and a grinding wheel will be exciting but probably hopeless at being O have fun new from canley £11.81+vat +post you must get a dial indicator on the hub flange check its running true , dont ignor bent drive shafts , all contribute to drum runout pete Link to comment Share on other sites More sharing options...
daverclasper Posted February 14, 2019 Report Share Posted February 14, 2019 13 minutes ago, Pete Lewis said: dont ignor bent drive shafts Goodness. Not thought of that. I suppose unless crunched the shafts stay true, if your suspensions up to scratch, or can age cause metal fatigue that causes untrueness? Dave Link to comment Share on other sites More sharing options...
johny Posted February 14, 2019 Report Share Posted February 14, 2019 As you say little chance of home machining success but with the Vitesse/GT6 drums at around 100 pound a pair incl delivery (and then they might later go oval) its probably worth a go! Good point on the flange running true though.... Link to comment Share on other sites More sharing options...
Anglefire Posted February 14, 2019 Author Report Share Posted February 14, 2019 1 hour ago, poppyman said: With the brake test only marginal, have the brakes been adjusted correctly? ie with both handbrake cables disconnected, and do the cylinders slide on the back plate? If so the brakes should still work ok, It's just puzzelling me a bit...... Tony. I should have said the hand brake was marginal, the main brakes were ok, but not brilliant. Subsequent to the MOT test, I have improved the brakes - mostly by using them as they were basically brand new and not even slightly bedded in, I've also since replaced the slider locking U plates - and fitted them the correct way around 🙄 and the hand brake was also adjusted but still has too much travel for my liking. The weather looks promising for the weekend, so I have bought a new pair of drums and shoes and I also have a set of Mintex 1155 (Or whatever the number is!) pads to go on the front. If the new drums don't improve the adjustment process and give me less shoe to drum gap at rest, then I will look elsewhere at things like drive shafts. Link to comment Share on other sites More sharing options...
johny Posted February 14, 2019 Report Share Posted February 14, 2019 ok let us know how it goes... Link to comment Share on other sites More sharing options...
poppyman Posted February 14, 2019 Report Share Posted February 14, 2019 31 minutes ago, Anglefire said: I should have said the hand brake was marginal, the main brakes were ok, but not brilliant. Subsequent to the MOT test, I have improved the brakes - mostly by using them as they were basically brand new and not even slightly bedded in, I've also since replaced the slider locking U plates - and fitted them the correct way around 🙄 and the hand brake was also adjusted but still has too much travel for my liking. The weather looks promising for the weekend, so I have bought a new pair of drums and shoes and I also have a set of Mintex 1155 (Or whatever the number is!) pads to go on the front. If the new drums don't improve the adjustment process and give me less shoe to drum gap at rest, then I will look elsewhere at things like drive shafts. That sounds like a plan...... But always disconnect the handbrake cables before adjusting the footbrake Mark, or they wont be adjusted right...... Hence the poss reason for poor handbrake. This problem affects a lot of cars not just Triumphs. Even with so called self adhusters. Tony. 1 Link to comment Share on other sites More sharing options...
johny Posted February 14, 2019 Report Share Posted February 14, 2019 well I would adjust the handbrake as the manual says.... Also theres someone on ebay who sells custom made extenders for our rear drum handbrake operating levers so that shows how common it is for owners to feel their handbrakes are poor! Link to comment Share on other sites More sharing options...
Pete Lewis Posted February 14, 2019 Report Share Posted February 14, 2019 If you lengthen the whell cyl lever you increase the in car handbrake lever travel If adjusting the rears its important the cable is disconnected to ensure it is not holding the leading shoes open , really lock the adjuster Firmly to expand the shoes, reconnect and adjust the cable to a neat fit , back off the adjuster to free the brake, Best to support the wheels in a near running height or the cable setting is false if done with axles hanging . Do absolutely do make sure the trailing shoe is the right way up, I wish I had a £ for every one ive found wrong over the years. Get the basics right and the brakes are realy good If fitting Mintex 1144 there is a bedding in proceedure which must be adhered to if you want them to work When back on laptop i will add the process Pete 1 Link to comment Share on other sites More sharing options...
Anglefire Posted February 14, 2019 Author Report Share Posted February 14, 2019 Thanks all. Yes I know the current shoes are the right way around as I checked when it was last mentioned 😂 Pete, When you say “neat fit” do you mean reasonably tight or just nipped up to little slack? - as I know they aren’t at the moment. Link to comment Share on other sites More sharing options...
johny Posted February 14, 2019 Report Share Posted February 14, 2019 Certainly make sure the handbrake cables are not under tension with the handbrake released (this should always be the case) before tightening up the adjuster. The handbrake lever should then only need to go 3 or 4 clicks to fully apply the handbrake. Dont forget to adjust both the cross cable AND handbrake cable to maintain the central pivot (which also has its own adjustments which may have been fiddled with.....) around the 90º position. Finally I would argue that although the brakes can be fine our handbrakes are always going to be on the weak side especially compared with a modern...... Link to comment Share on other sites More sharing options...
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