Works in Progress
January 19, 2002
The Great Taper Pin Swap & Ring Gear Mystery
Like any car, there will be things that break and regular maintenance items that need fixing, so I thought I would chronicle some of the more interesting, at least to me, items that I run across on my car. There are many excellent sites on the web with detailed information about just about every aspect of Triumph ownership, so I'm not going to try to recreate the wheel, but I will add my own personal experiences and opinions to what I have done in the hopes that it may be of assistance to others. I am also going to add my own words of wisdom, thoughts and bone-headed mistakes I've made which I will put in bold face.
I also would like to add that I am lucky to live in an area where there is a thriving group of Triumph owners who love to share their experiences and are more than willing to lend a hand when someone needs a bit of assistance. So a special nod to the members of the Georgia Triumph Association (GTA) who showed up for their assistance on this matter.
Let me recap as to why this "tech session" as we like to refer to it came to pass. When I purchased my car there was an occasional issue with the starter appearing to freewheel. That was diagnosed correctly as the ring gear slipping off of the flywheel and remedied. At that time I also replaced my clutch and related parts since the transmission was going to be out anyway. This was done less than seven months ago - my how time flies when you drive a Triumph.
Anyway, that "sound" the starter made while freewheeling started to reappear and I got worried. The transmission started to get balky again like the clutch cross shaft taper pin was broken... again. Since the sound of the starter was the same, I got to wondering why I would have an issue with the ring gear and settled on the fact that since the ring gear was heated twice during installation on the flywheel that it had not quite "taken." The balky shifter and probable broken taper pin was not uncommon so I put the word out that I wanted to pull the transmission to fix these issues once and for all, or at least a year or two. The response was overwhelming with about a dozen of fellow like-minded car nuts showing up at a member's garage for the operation.
Since I "knew" exactly what my issues were I figured it would go quickly and smoothly, which meant that it would be done in about three hours. Mistake #1. Luckily my wife and offspring were out of town for the weekend so I didn't have a personal deadline to meet.
Ring Gear Issue
We pulled the transmission and inspected the ring gear. Guess what, my 90% confidence factor was wrong. The ring gear was sitting just where it's supposed to be. Oh well, we chalked that up to something to mull over later after we fixed the other issue. I will mention that when the new ring gear was installed last spring it was moving off the flywheel, which according to those more knowledgeable than I, is not unusual with a car over 100k. The reason for this is that all TR6's manufactured retained the same design as the earlier TR4 & TR250 which had a starter that engaged from the rear thus the ring gear teeth were tapered towards the rear. Given 100 thousand miles of starting the engine, the starter basically pushes the ring gear rearward since the TR6 starter engages from the front.
So what is the problem this time? The quick answer is "I'm not sure." If there is one thing that I'm learning from owning a Triumph it's that it's rare that there is one lone answer to whatever problem you might have. It usually can be one of at least three things and typically any of the three make a lot of sense. Now those three things can vary in complexity, so if you are stumped it's usually a good idea to do the simple one first - it probably needs to be done anyway.
The starter is usually the most likely suspect in a case like this. Starters only last so long even when they are rebuilt well and you can almost bet that that wasn't the case. But I had the starter checked out the first go round and it was fine. Now that doesn't mean it still isn't the culprit, but it is enough of a reason for me to look elsewhere. The other possibilities involves wiring and that can mean one of two things.
One, the old wiring may not be transmitting enough juice to tell the starter to engage properly or it could be a loose wire somewhere. The other possibility is that I have a bad ground wire.
Broken Taper Pin
If you own a TR6 and if you haven't had this happen to you then at the least you probably know someone who has had theirs fail. When I fixed the ring gear last year I had a broken taper pin and didn't even know it, so I was confident that this was the reason for the poor disengagement of my clutch. Basically, it was hard to get it in gear, especially 1st and reverse. If my taper pin was broken then that would result in less travel and the clutch would not totally disengage. Made perfect sense, but once again I was wrong. However, what I found was both interesting and something that everyone should know about.
When we pulled the taper pin out of the cross shaft we discovered that it was not broken. It was however bent. It was bent because the taper pin, which was one of the hardened ones purchased from Moss, had not and could not be inserted all the way through the cross shaft. I checked a new pin from TRF and it would not go through either. So I had a problem with a poorly made cross shaft. Incidentally, the Moss taper pin was slightly larger than normal- not in diameter, but the head of the pin.
What to do? Well, we ever so slowly honed out the smaller end of the cross shaft until the taper pin could extend through the cross shaft and seat properly in the other side of the clutch fork. Lesson: be careful about replacement cross shafts. Another club member went home and checked his the next day and had the same issue.
Uprated Throw Out Bearing
I have it on good authority that the replacement throw out bearing made today aren't of the same caliber as they were in the past. An alternative is to go with a uprated throw out bearing that comes out of a Toyota Land Cruiser. This bearing is a heftier bearing and it is also slightly thicker (by about 1/4 inch) which should give a later engagement of the clutch. I went with the uprated bearing and after driving the car I don't notice any difference in drivability, which is good, and since it looks beefier then I have high hopes that it will last quite some time. The bearing is a drop in replacement for the stock bearing so no modifications are required.
Numerous people have taken measures to either strengthen or improve upon the taper pin. One excellent source is the tech area of the Buckeye Triumphs site. However, the different methods can be broken down to three choices: weld the fork to the cross shaft, add a bolt to the fork and/or use a slightly different taper pin.
I chose to use the stock pin. Many believe that the pins break due to either improper installation. If your sleeve is binding on the input shaft that could also cause an issue. I did none of the above, but I did drill a very small hole in the clutch fork to make removal of a broken pin an easier task.
As long as you have your transmission out, it's a good thing to check those usually inaccessible things, one of which is the reverse light switch. I knew I had a problem since my reverse lights had never worked. I had check the usual suspects: bulbs, connections and fuses so my money was really on the switch. I'm no electrical engineer so Ohms and volts don't register a whole lot with me, but we did check the existing switch and it seemed to have a high resistance although I don't know what the proper resistance should be. I think I need to crack open Dan Master's book again.
Anyway, we cleaned the connections to the switch and crimped them down tight onto the new switch and I'm happy to report that this quick operation did in fact solve my problem so now I've got reverse lights again.
Putting it all back together, but wait...
The sun had gone down so it was time to draw this "three hour cruise" to a climax. Most of the attendees had also decided to make their exit so the three remaining people slipped the transmission back into the car and hooked everything back up. The process of removing and installing the transmission is really not that difficult if you've got the necessary tools and a couple of extra hands. I know that this can be done alone, but I would recommend it since it's so much easier with two and preferably three people to help out.
After getting everything back together, it was time to start the car and hopefully smile at our job well done. We cranked the car up and attempted to slip it into gear. The transmission was still not cooperating and the car wanted to move even with the clutch pedal fully on the floor. We scratched out heads and did a quick mental check as to what the problem could be. We quickly decided that there could be no mechanical reason for our issue and that a quick bleeding of the clutch might solve our problem. The clutch was bled and air was in fact found in the system.
I hopped in the car to start it up and give the tranny a try once more. This time the car easily moved in and out of gear so believing that all was well, I bundled up in the car for the 45 minute trip home on a dark and rainy night. On a side note, I love driving my car on beautiful days and am not overly intimidated by big city highway traffic, but driving a TR6 at night in the rain on a major interstate in Atlanta is a different story. The glare of lights, reduced visibility and the carelessness of today's drivers will make you extremely cautious to say the least. However, I soon figured out that creeping along slower than the flow of traffic was not the safest choice and to speed up to my normal speed allowed me to have a better view of my surrounding travelers.
Well, that's beside the point so did our operation totally fix my issue? At first I wasn't sure due to the incredible noise and fear of 18-wheelers and SUV-driving-idiots, but I began to doubt that everything was still 100%. By the time I reached home I was certain that while we had improved things dramatically, we still had not totally solved the issue: that being not enough clutch travel.
New Clutch Master & Slave Cylinder
There was really only one other thing to try to fix my issue, but a new master and slave cylinder seemed to be in the cards anyway since I had recently noticed my clutch master cylinder was weeping. What I didn't realize was how much lost hydraulic pressure or boost I might be losing due to these old or leaky components. So I ordered a new master and slave cylinder and set aside a couple of hours the following weekend.
The removal and installation of a clutch master and slave cylinder is truly a simple process; pretty much a unbolt the old and bolt in the new with the only somewhat tricky part being the bleeding process. However, with the help of a neighbor it was done in fairly rapid fashion.
I did have one decision to make since I was installing a new master and slave cylinder. That is what type of fluid to use. My car is an attractive driver and while it's no trailer queen, I was irked that the old leaky master cylinder had removed some paint from my firewall. There are two ways to make sure this didn't happen again; keep a careful eye on the master cylinder or switch to silicon fluid.
There are plenty of people out there who will strongly tell you not to use silicon fluid in the brakes or clutch. The reasons for this are well documented, but basically silicon will not absorb water (not good), is not good if you race your car (I don't), is more prone to leakage (usually only if introduced to a system that has not been rebuild), but will not eat paint (which I liked). So I made the switch and didn't notice any difference in the operation of the clutch versus DOT4 fluid. Plus it's a beautiful shade of purple so if it starts leaking then I will know exactly where to look.
Now I also need to replace my brake hoses but I most likely will stick with DOT4. Why? Well, for one thing I'm not planning on a total rebuild of my brake system, so I am worried about leaks and secondly I'm not sure it will hold up as well on the "cruises" our club occasionally takes into the mountains. If and when I get around to doing a complete restoration of my car then I might and probably will switch to silicon in the brakes as well. That is unless I set the car up more for performance (which I want to do) so then again I might just stay with DOT4.
The moment of truth had arrived to see if all these hours of work and frustration had finally fixed my balky transmission and it had. I cranked the car up and eased the car into gear and took it for a half-hour shakedown cruise. Everything worked as planned and I like a plan when it works.
Final thoughts? It's a good idea to know how long it's been since certain components on your car have been rebuilt. Everything has a certain lifespan and will need fixing or rebuilding sooner or later. I'm also saving my master and slave to attempt a rebuild on to see if in the future this is an avenue that I would choose. But right now I'm just tickled to death that one problem is knocked out and I'm back on the road again.
Installing New Brake Lines -----> New Master Cylinder
I've been putting off installing new brake lines for quite some time so I finally finished procrastinating and set about this chore. This wouldn't take too long after all it's just a few nuts and bolts right? Well, nothing is ever as easy as it's supposed to be.
Since I am going to be removing all the brake fluid from the system, I started at the driver's side front wheel and bled all of the fluid out of the rear portion of the reservoir (remember that the rear portion is actually for the front brakes and vice-versa). Well that went fine so I moved on to the rear brakes. I cracked a bleed nipple and fluid came out, but it was the clear new fluid from the rear portion. Hmmm, that's odd. I then try the other wheel. Same thing. Next I remove a brake line from the reservoir itself and fluid comes out, but once again it's the wrong fluid. No matter what I did, I was only able to get the front brake fluid out of the lines. This was strange since the TR6 has two separate braking systems and the fluid never gets co-mingled.
Well, I consulted with friends locally and the always helpful Triumph email list and it was pretty apparent that my master cylinder was doing something really bad. I don't know if one of the pistons is missing in the MC or if the plungers were simply so deteriorated that they weren't functioning properly, but I had to get a new one. I decided against a rebuild kit since I wasn't confident enough to rely on my rebuild yet although I am going to rebuild the old one as a spare.
The disassembly and installation of a brake master cylinder is a piece of cake. Two bolts and two brake lines and you are done. I cleaned the area where the MC attaches to the brake servo since it was fairly nasty. After inspecting the connection area on the MC I'm not surprised that I had problems. The mating area was very dirty. I knew the fluid needed to be changed and I'll post a picture soon, but I will reiterate that changing your fluid regularly is imperative.
So after applying liberal amounts of PB Blaster, all the brake lines are pretty easy to remove. It is amazing how grungy the work is, but there's nothing terribly complicated about the removal or installation of new brake lines. The job always takes longer than you plan so allow a couple of hours to do this and bleed the system. Be careful not to torque any of the brake lines themselves as constriction of flow of brake fluid is not a good thing.
I then successfully bled the fluid out of the rear brake reservoir so I thought that everything was just about done. Wrong again. Now I'm not getting fluid out of the front brakes. I cracked the line at the reservoir and that fixed that.
The next day I took the car for a test drive and all I can say is that I had forgotten what a hard pedal feels like. If your pedals are mushy then it's time to change your fluid people. I only had time for a short drive and it was a good thing because I had one last dumb thing up my sleeve. About a mile from my house I notice that my car is slowing down much faster than it's supposed to and the engine is still running. What now? Well, I had left one of the rear brakes tightened down a little too tight so the brakes got hot and I'm not going anywhere. I drove the car a couple hundred yards to a friends house, borrow a car and use the travel tool kit that my wife gave me last year (thanks Honey) to loosen the offending brake. The brake is fairly warm so it needs some time to cool off so I decide to come back in an hour and everything is fine.
Another job successfully done. I continue to learn more and more about what makes these cars tick, make a few mistakes along the way and enjoy every minute of it. Well, maybe not every minute, but it sure beats dropping it off with a mechanic and paying exorbitant bills.
Oh, by the way I also installed a pair of new front shocks. I went with the stock replacement shocks for now. The front end is much tighter and I will continue to research whether Spax, Carrerra or Koni's will suit my needs in the future, but the price was right and after replacing a clutch master and slave and then a brake master in a few short weeks funds are kind of low for anything extensive for a while.
So much has happened in the short time since I updated my site, but here goes. When last we met I was waiting on some parts for the brakes (I think). After these few parts arrived I installed the new brake line and bled the brakes then set off on a short drive to make sure everything was fine. After driving about three miles or so and thinking that everything was fine, I was just about to enter the interstate for an extended "test drive" to blow the cobwebs out. But something seemed odd and luckily I stopped on the entrance ramp. Yep, brakes were sticking again. So I cool my jets for a half hour and limp home.
I put the car up on jacks and discover that I've got a new safety feature entitled "4 wheel lock" as in every wheel is binding. Shocked and worried don't adequately describe my feelings, but I got to thinking. After a bit of thought I determined that something is amiss with my new brake MC, but WHAT? Initially I had some recommendations that the new one was defective, but thanks to some help from other Triumph guys on the web I am asked to check the actuating rod in the brake servo. This rod is what pushes against the brake MC to exert brake pressure. Sure enough this rod is protruding ever so slightly above the edge of the servo lip and should not be.
Next I attempt to adjust the rod with no luck. I try again and with the same result. The problem is that this rod is basically lightly pressing the brakes on at all times and when they heat up you know what will happen. Finally, since I can't get the rod adjusted and don't want to pull the servo apart for fear of never getting it back together, I used a simple and inexpensive solution. I insert two slim washers onto the bolts that secure the MC to the servo. Guess what, this appears to work fine. Now, I might revisit this issue later, but I've got to get the car ready for a trip in the next few weeks and time is starting to run tight.
Springs and Shocks and Brakes Again?
When I purchased my car, it had a bit of an unusual stance, with the front being very low and the rear being just the opposite. It is my understanding from talking to the previous owner and others that what are commonly known as competition springs sold 5-7 years ago had a problem of raising the rear ride height; I had this problem. It is really only a cosmetic issue unless you are a serious racer which I am not. So in a fit of boredom I decided that I wanted to change the springs. There are basically three choices: stock, sport and comp. The stock springs are just that, the sport springs are stiffer, but maintain the stock ride height and the comp springs are slightly firmer yet, but also lower the car about an inch. Some people have mentioned that the comp springs are too firm and really give you a bone- jarring ride. Well, the TR6 is a rough riding car compared to any modern vehicle and I was not against a roughly 20% increase in spring rates so I went with the comp springs for the rear.
In the meantime I had replaced what looked like stock shocks on the front with new stock shocks and had some issues with tire rubbing. So that meant I should do something to the front as well. I think it's a good idea to have a matched set of springs so I ordered a set of the comp springs for the front. Now all I needed to do was to figure out what shock I was going to go with on the front.
Since I knew I wanted to go with a premium front shock, I had basically three choices: Koni, Spax, and Carrera. Everyone knows who Koni is, but I wanted some feedback from actual users of these shocks to try to make the most informed decision I could make. Unfortunately, the response was slim. The Koni's are good shocks, but are not adjustable on the car, the Spax are adjustable on the car which initially swayed my opinion. The Carrera brand of shocks caters to racers. I had heard good things about Carrera, but at first the cost seemed prohibitive. I called Carrera back a second time and got myself educated on shock technology. I also found out that I could get the Carrera shocks locally for much less that both the Koni and Spax shocks so the decision was made.
I've not had a chance to see the performance of any of these additions either because they aren't on the car yet , but I'm close.
Let me also bring to your attention one issue you may have if you are ever replacing a set of rear springs such as I had with the higher ride height. The replacement of rear springs is supposed to be one of the easier jobs you can do on your TR6, but nothing is ever easy for me. Since these old springs make your car ride higher you can surmise that they are taller than stock springs, and you would be right. To replace a set of rear springs you are supposed to only have to place a jack stand under the rear portion of the frame, remove the bolt from the shock link and then lower the trailing arm until the spring can be removed. However, with a taller spring than stock this will not work. I tried various homemade spring compressors with no luck so the only solution is to unbolt the outer axle shaft to allow the trailing arm to be lowered sufficiently to allow removal of the improper spring. The problem arises out of the fact that when you are performing the "normal" procedure, the trailing arm will not go low enough and will rest on part of the frame. Unbolting the half-shaft is not nearly as bad as I had thought since you are only removing four bolts from each axle. Once this is done, the trailing arm will go down sufficiently to allow you to yank out the old spring and pop in the new one. This will not have to be done again since either stock or comp springs are shorter than the older comp springs. I measured and found that my old springs were almost two inches taller (12" vs. 10 1/8") so this makes perfect sense. It's good to occasionally run into something that makes sense.
Well different issue this time. I had taken my car to get a front end alignment months ago and was told that one of my ball joints was bad. I also ignored this issue for at least six months. However, since I was planning a trip to Florida soon, I thought it might be a good time to replace the tie rods, ball joints and repack the front bearings. So one Saturday I replace the bearings in my front left wheel and pack it full of grease. It took me a while since it's been a while since I had done it, but I was ready to quickly knock out the front right wheel on Sunday afternoon. Wrong again? First, I can't find the new bearings for a half hour, but to my shock and surprise I find that my brake rotor had a major gash in it when I flip the hub over. I can only guess that I picked up a rock and it lodged between the pad and the rotor, but whatever the cause I picked up a set of new rotors and pads.
Now, this is getting a bit expensive and I am replacing many more parts than I had planned on, but the brakes are usually quite important, so I bite the bullet and march on.
I then pull off the calipers to replace the pads and pins and I'm dismayed once again. I'm no caliper expert, but these didn't look good so now I've got to get a rebuilt set of calipers.
Stainless or normal?
I'd always heard that when you get our calipers or wheel cylinders rebuilt that you should get stainless pistons in place of the normal material. It made sense as stainless is less prone to rust so that's what I planned on until I found out both the cost and another bit of unusual information. It appears that the stainless pistons are a fairly soft metal and while they won't rust as easily, they tend to wear quicker which could lead to leaks. I'm not sure which is better, but given the fact that this is not a daily driver and will have the fluid changed on a regular basis I went with a rebuilt set sans stainless.
Gunst Throw Out Bearing Replacement
On April 13th, 2001, I placed an order with The Roadster Factory. I had owned my TR6 less than a month, and knew that I had to replace the ring gear on my flywheel. I wasn't looking forward to pulling the transmission on a car that new to me, but since I was at it, I thought it prudent to replace the clutch and related components. This way, I KNEW that I wouldn't have to perform this operation again anytime soon. Boy was I wrong,
To make a long story short, I pulled my tranny, found the infamous taper pin broken, but then proceeded to replace any possible worn component. Should have worked right? Nope, I pulled it again in January of 2002. See above write-up. But things still weren't right.
This time before I launched deep into ordering parts, I thought it prudent to do some serious research. About that time I stumbled upon The Buckeye Triumphs Website. What a fortunate turn of events for me. By that time, I had also been a list member of both the Six Pack & Triumph email lists. I started to gather information and many other questions. The end result is that I decided to follow the lead of Nelson R. & Dick T. and install a Gunst throw-out bearing, Sachs clutch, and misc. new components.
The problem was that Nelson had put out the news of a group order for the bearing about six weeks ago, and the order was "full-up." Now what am I going to do? Well, another list member offered me his spot on the order.
Fast-forward a couple of weeks, and I've got lots of new shiny parts sitting in my work area, on my desk, and the floor around my office. A fellow club member, thanks Brooks, offered to help me with the install and we set a date of January 25th - almost a year to the date since I pulled it last.
Oh, I forgot to tell you why I had to pull it again. Well, the easiest way to describe my clutch motion or feel was dreadful. If you look at the Sticky Clutch story on the Buckeye site, you will get an idea what I was dealing with. And not to take anything away from that poor soul, but mine was awful. The clutch motion was jerky and seemed to engage about 1/8" off the floor. I knew it was bad, but didn't realize how bad until I drove Brooks' fabulous Six on the way back from the 2002 SEVTR in Jekyll Island. His car shifted like brand new, no, make that like a brand new modern car.
Back to the installation, we started mid-morning on February 2nd. Why not the 25th? I decided at the last minute that I simply couldn't do this without having my flywheel resurfaced. The easiest way to do that was to buy a used one, which I did, and have it machined. Within an hour the interior, transmission, and clutch were out. So we started to investigate what had caused the problem to begin with.
The LUK pressure plate showed obvious signs of wear in two distinct spots. The Koyo bearing seemed in decent condition. We found that the pilot bushing appeared be out of spec both in I/D & O/D dimensions - too big in both cases resulting in it being very tight in the flywheel, yet loose on the input shaft.
We also noticed that my newly machined, but used flywheel, that I had just purchased was not usable. Take a look and see why. Well, we had to go with the old flywheel, but it appeared in good condition. I also replaced the cross-shaft out of a TR4, which enables you to externally grease the cross-shaft bushings. Another step I took was to cross-drill the fork and insert a bolt to do away with worrying about broken taper pins. Here is a look at the final product prior to assembly - sans t/o bearing. And here's a look at the Sach's unit on the flywheel.
A while later we managed to coax the transmission back into the car. That is rarely a fun process, but the final product was worth it. The result is really beyond proper description. Where I used to have a very heavy and jerky clutch that engaged just off the floor (even with the slave pushrod in the top hole), now I had a velvety smooth clutch that engaged midway off the floor.
Notes and observations:
* The LUK clutch is simply too heavy a clutch - toss yours
* Beg, borrow or steal a Gunst throw-out bearing. Not currently available from any U.S. suppliers, but I hope that changes soon.
* Liberally lubricate the bushing, input shaft, and related areas with a good lubricant.