Lord Flashart Posted August 2, 2016 Report Share Posted August 2, 2016 Took the car for a spirited drive tonight and on dropping out of overdrive 4th, I heard what sounded like gravel hitting the underside of the car. Then a few minutes later I noticed the engine was revving much more freely than it normally does in OD top! I'm guessing something has let go on the clutch pressure plate. When I think about it, the clutch has felt a bit slow for a while. So where has the best deal on a clutch kit for a '62 TR4? I'll be removing the gearbox tomorrow. Paul Quote Link to post Share on other sites
Motorsport Mickey Posted August 2, 2016 Report Share Posted August 2, 2016 Before you start pulling the gearbox try and define whether you have a problem with the overdrive rather than the clutch...saves replacing the clutch and then finding you have the same problems. The clutch is under greatest pressure in the higher gears the multiplication of torque is greatest there, so 4th gear overdrive will show up the early stages of clutch slip. However if you park up the car stick it in 4th gear with the handbrake on and the overdrive disengaged you can then try and provoke the clutch into slipping (be a bit brutal with the clutch disengagement, you need to see if the revs don't correspond with the engine loading). If all is ok then it's possible you have a problem with the overdrive cone clutch or it's internals. Mick Richards Quote Link to post Share on other sites
ChrisR-4A Posted August 2, 2016 Report Share Posted August 2, 2016 Or drive at about 50 in 3rd hold speed steady an apply some brake with left foot. If clutch is ok engine will virtually stall, of not revs will surge. Quote Link to post Share on other sites
Lord Flashart Posted August 2, 2016 Author Report Share Posted August 2, 2016 Cheers guys, Thankfully, it's also slipping when out of overdrive so in fairly confident it's the clutch. I'll know more tonight when I pull the gearbox. Paul Quote Link to post Share on other sites
RogerH Posted August 2, 2016 Report Share Posted August 2, 2016 Hi Paul, I'll be thinking of you. I've had my box out twice in the last two weeks - I'm getting quite good at it. If you only need to change the friction plate then it should be quick and easy. If you need to replace the release bearing carrier consider machining the 45' chamfer at the back of the carrier into a rounded profile. I think the sharp edge on mine was digging in (for some odd reasons) - I'm hoping the rounded edge will solve this. Roger Quote Link to post Share on other sites
Lord Flashart Posted August 2, 2016 Author Report Share Posted August 2, 2016 (edited) Thanks Roger, Removing the gearbox is my least favourite job! Putting it back is always a pain in the arse. I've ordered a complete new clutch kit so hopefully by the time it all turns up here I'll have everything a new to mend it. I'll have a look at machining the release bearing if I use it. Paul Edited August 2, 2016 by Lord Flashart Quote Link to post Share on other sites
RogerH Posted August 3, 2016 Report Share Posted August 3, 2016 Hi Paul, what I did to help fit the GB - crocodile jack under the engine in order to help alignment. electric scissor jack under the GB to align that. removed the GB rear mount complete and had a 2x1" piece of wood there to help waggle. Put GB in 2nd gear - in order to rotate the splines. Use the top attachment holes/studs to help height alignment by sight. Keep an eye on the gap between the engine and GB to ensure it is even - this helps the shaft to be square in order to slide in. I also found that the bronze carrier made in the last 10 years or so is on the soft side and the fork will dig in very quickly. The steel carrier needs anti-rotation pin - otherwise if it spins it will get hot and possibly cause problems. Good luck. Roger Quote Link to post Share on other sites
Steve Priest Posted August 3, 2016 Report Share Posted August 3, 2016 Liberal use of category A swear words also helps the gearbox to go back in Good luck! Steve Quote Link to post Share on other sites
RogerH Posted August 3, 2016 Report Share Posted August 3, 2016 Quote Link to post Share on other sites
Lebro Posted August 3, 2016 Report Share Posted August 3, 2016 Liberal use of category A swear words also helps the gearbox to go back in Good luck! Steve I have never found that to be the case. The box only goes in after you have almost given up. Bob Quote Link to post Share on other sites
nigethomas Posted August 3, 2016 Report Share Posted August 3, 2016 Roger, I think we are experts at removing and refitting TR gearboxes by now eh Nige Quote Link to post Share on other sites
RogerH Posted August 3, 2016 Report Share Posted August 3, 2016 You could say that. I'm certainly getting faster at it. Roger Quote Link to post Share on other sites
Tony Posted August 4, 2016 Report Share Posted August 4, 2016 hi All, last time i had to refit my gearbox i fitted old manifold studs into the holes that normally take the bolts, gear box slid in perfectly, with no need to wiggle it about to line it up. tony Quote Link to post Share on other sites
Lord Flashart Posted August 6, 2016 Author Report Share Posted August 6, 2016 The long stud method is how I do it. I fit studs that are as long as possible and then it all lines up fairly easily Still I job I dislike! Paul Quote Link to post Share on other sites
Geko Posted August 6, 2016 Report Share Posted August 6, 2016 Liberal use of category A swear words also helps the gearbox to go back in Good luck! Steve Being multilingual helps a lot. That's why Brits are struggling so much to get it (back) in Quote Link to post Share on other sites
Lord Flashart Posted August 6, 2016 Author Report Share Posted August 6, 2016 Pulled the 'box and can't see anything wrong!! I was expecting to see something obvious. Anyone know what the thickness the clutch friction material is meant to be? It doesn't look too bad, but maybe just worn. I'll chuck a new clutch in anyway and hopefully That'll sort it. Paul Quote Link to post Share on other sites
PeteT Posted August 6, 2016 Report Share Posted August 6, 2016 Hi Paul, I hate that scenario, when you can't identify the cause of the problem. It's happend to me so many times over the years I've learned to keep digging until I'm sure I understand what's wrong. The alternative is trusting to luck and mine is usually lousy. Regards, Pete Quote Link to post Share on other sites
Lord Flashart Posted August 6, 2016 Author Report Share Posted August 6, 2016 I agree Pete. When the clutch started slipping and I heard the tinkling of something metallic, I assumed when I stripped it all, that the fault would be obvious. I'll still fit a new clutch and cover since I'm in there, and hopefully that'll sort it out. Paul Quote Link to post Share on other sites
RogerH Posted August 6, 2016 Report Share Posted August 6, 2016 Hi Paul, this may be completely wrong. Last week I had to remove my box as although the pedal would come up but the clutch remained depressed. I found the GB extension nose was slightly out of vertical alignment with the input splined shaft. I assume that the diaphragm (TR4A) fingers were cocking the bearing and jamming the carrier on the extension. Look for subtle signs of wear on the extension. My present cure has been to round off the 45' chamfer on the rear of the carrier. And to grease the extension where the carrier slides. Roger Quote Link to post Share on other sites
BlueTR3A-5EKT Posted August 7, 2016 Report Share Posted August 7, 2016 Hi Paul, this may be completely wrong. Last week I had to remove my box as although the pedal would come up but the clutch remained depressed. I found the GB extension nose was slightly out of vertical alignment with the input splined shaft. I assume that the diaphragm (TR4A) fingers were cocking the bearing and jamming the carrier on the extension. Look for subtle signs of wear on the extension. My present cure has been to round off the 45' chamfer on the rear of the carrier. And to grease the extension where the carrier slides. Roger Roger, That sounds like the classic 6 cyl 'ratchet clutch' caused by misalignment of the bellhousing to the rear engine plate due to not having the dowel bolts fitted. 4 cyl has a couple of 3/8"dowels banged in the engine to gearbox mating face.....are yours there? Block dippers are apt to remove and lose them when they do the block dipping/cleaning, along with all the core plugs, cam bearings.etc. Use of copper type grease is good. A non sticky type of lubricant that did not attract the clutch dust would be even better. Early cars with a spring type clutch have a bronze release bearing carrier as did some TR4A with diaphragm clutch. The later spec was a cast iron carrier with a dark coloured anti friction coating. The market saw a lot of phosphor bronze carriers made for diaphragm clutches to alleviate the sticking carrier issue with CI carriers. Moss offer it as 147858X. http://www.moss-europe.co.uk/sleeve-release-bearing-carrier-147858x.html?assoc=124763 Do not forget the cross pin to stop the carrier spinning on the forks. item DS811 http://www.moss-europe.co.uk/roll-pin-release-fork-to-carrier-ds811.html?assoc=124764 Paul.. Have you also added an extra securing dowel/bolt to your clutch fork/cross shaft. The taper pin being a horrid weakness. Worth doing while you are in there and simple to do. Cheers Peter W Quote Link to post Share on other sites
RogerH Posted August 7, 2016 Report Share Posted August 7, 2016 Hi Pete, 'ratchet' clutch - I like that (but not the effect) The dowels are in place. There is a 0.015" misalignment between the splined shaft and the extension nose. There is a wear pattern on the extension nose to suggest the carrier gripping. So far the rounded back face where the chamfer was may be doing the TRick. The anti-roll pin would help reduce expansion due to temperature. Not convinced about greasing the extension nose - but it is working and so I'm happy. Roger Quote Link to post Share on other sites
Lord Flashart Posted August 8, 2016 Author Report Share Posted August 8, 2016 Thanks guys, I'm starting to wonder if it's all just worn out. I fitted this clutch five years ago, but I only changed the friction plate due to budget constraints! The parts should be here next week sonetime so I'll be able to measure and compare everything then. I also have a new master and slave lying on tbe shelf, so I might for fit them also to be on the safe side. Paul Quote Link to post Share on other sites
PeteT Posted August 8, 2016 Report Share Posted August 8, 2016 I'm sure Rodger will offer to slip it in whilst your having a cuppa. Sorry sounds rather rude that on reflection Quote Link to post Share on other sites
mike3739 Posted August 8, 2016 Report Share Posted August 8, 2016 I'm sure Rodger will offer to slip it in whilst your having a cuppa. Sorry sounds rather rude that on reflection Quote Link to post Share on other sites
Lord Flashart Posted August 26, 2016 Author Report Share Posted August 26, 2016 Fitted the new clutch and test drove the car today. No slip at all. So I'm not sure what the fault was. The only observation is that the clutch pedal fells a little heavier now, so I'm wondering if the springs in the clutch were just not up the job anymore. Anyway back to TR motoring for now. The first snow has hit the mountains not too far from us so it won't be long before the winter lay up! Paul Quote Link to post Share on other sites
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