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LexTR3
05-17-2011, 12:43 PM
Can anyone give me, or direct me to, instructions on how to remove and replace the distributor on a TR3. I want to send mine off to Jeff for a rebuild, but I will have to remove it myself.... and replace it when it has been rebuilt.

Your help, as usual, is much appreciated.

Geo Hahn
05-17-2011, 02:29 PM
Not much to it as I recall -- just undoing 2 nuts (1/2"?) that hold the plate that also forms the clamp. Then just lift it out.

Of course you'll have removed the distributor cap w/wires & vacuum line beforehand.

Since (I assume) the car isn't going anywhere until the unit comes back -- you might find it simpler later if you move the engine to TDC for #1 ignition (rotor more or less pointing at #1 spark plug). Having it there may make for less thinking when reassembling.

Stuff a rag or something in the hole left behind so nothing gets dropped in there.

Once you have it out take a look at the drive dog (the bottom of the unit that engages the shaft still in the engine) and notice that it is slightly asymetrical... i.e. the cross pin is not centered. This allows the thing to be reinserted only one way.

You may want to find out how much Jeff wants -- i.e. do you remove the clamp, rotor, points etc. Even if you go with Pertronix you will still want a set of points for a spare.

Chapter 4 section 6 of the Haynes... page 98, in my edition.

LexTR3
05-17-2011, 03:28 PM
Hi, George,

Many thanks... I can count on you for good advice.

Your are right: the car won't be going anywhere until the unit comes back.

And thanks for the lead to Haynes.

Rhodyspit75
05-17-2011, 04:47 PM
Take a few pictures both with and without the cap. It will help with the orientation of the distributor when you go to put it back in.

LexTR3
05-17-2011, 05:55 PM
Rhodyspit75,

Good idea. Many thanks.

DNK
05-17-2011, 06:15 PM
Lex, do you have a manual?

Marvin Gruber
05-17-2011, 06:58 PM
As Geo said not much to it. You can remove by just loosening the horizontal jam nut and lifting straight up. Mark the position or take a picture before removing to refresh your memory when installing back. When you put it back in, rotate the shaft until it drops into place on the keyway, The keyway is offset to match the distr shaft key. Will only fit one way.

Marv

LexTR3
05-18-2011, 08:22 AM
Don,

Yep, I have several manuals, but I find that it is best to ask the BCF crowd before attempting these projects because the by-the-numbers approach of the manuals is good, but experience speaking is much better.

Marv,

I'm curious about all the emphasis on "marking the position" and "taking a photo" to make sure the dizzy is put back properly. Seems to me that if I leave the distributor clamp untouched, as Haynes recommends, that the dizzy will go on just as it came off without disturbing the timing. But, I assume that no matter what I do with the dizzy, I would have to recheck and probably reset the timing when I install the rebuilt distributor.

BTW. When I opened my old distributor, I found that the springs were so rusted that they were rock solid, without any flexing at all. At first I thought I would just replace them with MOSS replacements, but when the new springs arrived they were (a) not the same size as the existing ones, (b) end hooks were in the wrong configuration (on the same plane rather than 90 degrees to eachother). I called around and discovered that the springs I need are "the Holy Grail" of distributor parts -- no longer available. Jeff says he makes his own, but doesn't sell them to customers. I have ended up twistng the ends of the MOSS springs slightly to get the 90 degree position, which changes the tension some but this can be compensated for when resetting the timing. Has anyone else dealt with this problem?

TR4nut
05-18-2011, 08:29 AM
Even if you leave the clamp on the distributor, the clamp itself is slotted slightly where it attaches to the engine - so you will definitely need to retime the engine when you put it back on. Like Marvin suggested, it can be easier to just loosen the horizontal bolt and pull it out that way since you are going to have to retime anyway.

tdskip
05-18-2011, 08:36 AM
Do you have a timing gun? Used on before?

Kinda fun actually.

Rhodyspit75
05-18-2011, 08:54 AM
LexTR3, I always recommend taking a few photos before taking things apart. I don't know how old you are but I'm going on Medicare next month. A picture shortens the length of my ---hummm how was that before I took it apart--- time considerably. Ernie

LexTR3
05-18-2011, 09:46 AM
tdskip,

Yes, I use the Advance Timing Light to tune my car. It's easy... but I have been getting inconsistent readings because the springs in my distributor have had no effect. I hope that when new springs are installed, it will work better.... and later I plan to have the entire distributor rebuilt.

Ernie,

Ha, ha... you are a youngster! I have been on Medicare for some years. I agree that taking photos of work in progress is a good idea. I photograph everything I do on my car. But I was just wondering why marking and photographing is so important for replacing the distributor. (I don't doubt it... I'm just trying to understand what's going on).

Rhodyspit75
05-18-2011, 10:37 AM
While it is not imperitive that you do this, it will help you to reinstall your distributor back into a position that will get the motor started and then timed with your light. More important if the clamp is left on the motor or removed during rebuild.

LexTR3
05-18-2011, 12:14 PM
Got it... Looks like even if I leave the clamp on, reinstalling the distributor is going to require some fine tuning of the timing. That doesn't surprize me, and it doesn't appear to be a problem.

Any thoughts on the "Holy Grail" springs? I'm very surprized that neither the Roadster Factory or Moss no longer carry these springs, and that the ones Moss carries are not correct for the TR3 distributor.

TR4nut
05-18-2011, 12:54 PM
If you want to replace springs without a full rebuild you might get some success ordering from the UK. For example, Martin Jay, aka The Distributor Doctor, might be a good place to start: Advance springs (https://www.distributordoctor.com/distributor_advance_springs.html)

Other than the call to the UK the postage would be really low.

tdskip
05-18-2011, 12:59 PM
I think it is going off to Jeff for a full rebuild anyway Randy, but thanks for the source of the springs!

TR3driver
05-18-2011, 01:40 PM
Just how hard is it to find an "Auto Electric" shop these days? Used to be there was one in at least every large town; there was even one in Rensselaer, IN (where I went to high school, population about 5000). They would have a cabinet full of springs, and a distributor tester to see if the chosen springs gave the desired curve.

There's an old distributor machine in my shed, but it is probably going to stay there until I manage to retire.

LexTR3
05-18-2011, 03:49 PM
Randall,

The problem with finding springs at a local auto shop is that all the new springs have hooked ends that are in the same plane.

-- /////// --

This is right for a plate with two posts.

But my distributor has a post on the plate and a tab on the weight with a slot (as shown in the Moss catalog pictures). That requires a spring with hooked ends that are 90 degrees to eachother (one sideways and one up).

(
-- ////// --

If one hook is not 90 degrees to the other, the entire spring has to be twisted around for the hooks to hold the slot (in one plane) and the post (in the other plane), and the tension thus created flips the hook up and off the post.

It's this older spring with hooks at 90 degrees to eachother that people apparently are calling the "Holy Grail" of distributor parts.

As I said earlier, I bent the hooks of the springs that Moss sent me, but I don't know how they will work.

Marvin Gruber
05-18-2011, 06:42 PM
Timing gun on a Triumph? Quit using one 25 years ago. They work well on American stuff and will get you in the ballpark on a LBC but set it by ear. You will be able to tell the "sweet" spot. May take a few tries but found it to work out better.

Marv

TR3driver
05-18-2011, 07:34 PM
We already had that argument, Marv. I'm on your side, but Ed insists on using a light.

Bending the springs is exactly the sort of thing a shop would do, but of course both the length and spring constant are critical to getting the right advance curve. That's why the machine is needed, to measure the resulting curve and see if the springs are right. You can do pretty much the same test on the car, but you need either a timing wheel or a light that will compute advance to do an accurate check.

Marvin Gruber
05-18-2011, 08:24 PM
I have an old AC test panel ( about 4'sq) on wheels that was used in a Kmart garage back in the 70's. I been meaning to try it out to see just what it will do. Just haven't got there.

Marv

tdskip
05-18-2011, 11:37 PM
We already had that argument, Marv. I'm on your side, but Ed insists on using a light.

So for a newbie isn't a light an easier way to get ballpark?

Geo Hahn
05-18-2011, 11:45 PM
Must be a matter of personal preference but I would think the static method is the least mysterious (and thus good for a newbie) 'cause you can see the whole process of ignition happening right before your eyes in slow motion.

LexTR3
05-19-2011, 10:12 AM
My mechanic friend came by today (long-time experience with Triumphs, Austin-Healeys, MGs, etc., etc.) to repair my distributor.

As I said earlier, I couldn't find the properly configured advance springs for the weights in the distributor, so I ordered the ones supplied by MOSS and bent the ends into the correct angles.

My friend removed the old springs (rusted almost beyond movement and way too stiff) and installed the two lightest MOSS springs (modified by me) -- as recommended by Jeff the distributor guy.

Then, using an advance timing light (4 degrees advance) and his expert ear, my friend checked the timing. At last, we could set the timing at 4 degrees advance and, when the motor was revved up to 2500 rpm, the mark on the pulley advanced as it should and, when the motor returned to about 800-900 rpm, the mark returned exactly to the 4 degree mark. Then, revving the car to 3500, the mark moved out of sight (advance),and when the motor returned to about 800-900 rpm, the mark returned exactly to the 4 degree mark. My friend said that this is exactly what it is supposed to do and was not doing with the old defective spings.

My friend then tinkered with the mix and got things "just right."

He added that it would have been very hard to get this right just using the "static timing method." (I'm not taking sides here, but for me the advance timing light method is way easier than the static method.)

He also added (as most of you already know) that until the distributor is working properly and the timing is as correct as you can get it, no amount of working on the carbs or the idle will make the engine run well.

Lesson learned: the MOSS springs, although not exactly correct, can be used if correctly configured ones are not available. According to Jeff, you should use the two lightest springs. Just be very careful when bending the ends into the correct 90 degree configuration that you don't stretch the springs.

I won't say that this is "the way" to do it, but it works for me.

DNK
05-19-2011, 10:28 AM
Ed,It's is nice to have a friend with the experience of yours. I would keep him in a closet at home so you don't lose him.
Con grats

LexTR3
05-19-2011, 11:00 AM
Hi, Don,

Yes, indeed, this guy is a real treasure. He owned a foreign car repair shop here in town for about 30 years and it had the best reputation in the entire county. After he retired, with back trouble, he taught auto mechanics in the vocational high school for some years. Now he occasionally gives instructional sessions to car clubs. He's the kind of mechanic we all hope to meet: down to earth, very careful, skilled at finding ways around problems, knowledge from years and years of practice.

He's been a friend for at least 40 years. I hesitate to impose on his time to help me but he always counters by saying that I should call him any time because this kind of work is fun for him.

Car guys... I have found ... both locally and in this Forum, are great guys.

LexTR3
05-20-2011, 07:48 AM
Just a note to newbies... like myself:

From reading this thread, you will see that before you try to tune your car (balance carbs, set the mixture, set the idle, install new needles, etc.) be sure the timing is correct. This comes first; all the work on the other side of the car comes after.

Use the static method or the dynamic method -- or a combination of both (my preference) -- to get the timing as correct as modern fuels and old cars will allow. And don't just adjust the timing but look under the contact breaker base in the distributor and check out the two springs attached to the weights. If the distributor is 50 years old, it is possible that the springs will be frozen (rusted) solid or someone may have put in the wrong springs or -- unlikely -- a spring may be broken or have lifted off its post. New springs with the correct configuration are no longer available from the big suppliers, but you can adapt some Moss springs (see the thread for information). Also, if gunk has built up on the plate, clean it well, and put a few drops of clean engine oil (not grease) on the moving parts of the plate before reassembling.


Once the timing is correct, you have a fighting chance to continue with the tuning.

If anything I have said raises a red flag, the more experienced contributors to this Forum will correct me.

CJD
05-20-2011, 09:13 AM
Wow

It always amazes me which threads take off. There is 10 times more info on timing in this thread than in the service manual!

Back to the show.....

LexTR3
05-20-2011, 11:52 AM
CJD,

I have found the same thing. The service manuals leave a lot unsaid, so the good additional information from members of this Forum is of great help. It's why this Forum is "the best."

tdskip
05-20-2011, 01:32 PM
Ed,It's is nice to have a friend with the experience of yours. I would keep him in a closet at home so you don't lose him.
Con grats

LOL

LexTR3
05-20-2011, 01:56 PM
The number of practicing mechanics who know anything about these old engines and their components, carburetors for example, is growing smaller and smaller by the year. Moreover, forget about parts and tools. Our local NAPA auto parts store, for example, doesn't even have timing lights in stock and hasn't had a request for one for some years! When I describe to the guys who work there some of the things I'm doing on my car, they just give me a blank look.

TR3driver
05-20-2011, 06:23 PM
And don't just adjust the timing but look under the contact breaker base in the distributor and check out the two springs attached to the weights. If the distributor is 50 years old, it is possible that the springs will be frozen (rusted) solid or someone may have put in the wrong springs or -- unlikely -- a spring may be broken or have lifted off its post.
A better way to do this check, IMO, is to hook up a timing light and watch what the timing mark does as you slowly rev the engine up and let it back down. You should be able to see the mark appear to move steadily with rpm, not jump around or stay in one place. There may be an upper limit to the movement (depending on which distributor is installed), but it should not be until the rpm is fairly high.

This will point out problems not just with the springs, but also worn bushings or the point cam binding on the shaft.

Ed, I'm not questioning whether you can hit exactly 4 degrees BTDC better with a light; but rather whether 4 degrees is "exactly right". Most people still running 83mm liners find that they get more power and burn less fuel up around 8 degrees.

But since you apparently now have no idea how fast the timing advances, perhaps it is safer to stick with 4 degrees.

LexTR3
05-20-2011, 08:31 PM
Randall,

In fact that is exactly what my mechanic friend did -- With the new springs in place, he hooked up an advance timing light and watched the timing mark as he slowly revved the engine to 2500 rpms and let it back down. The mark advanced steadily with rpms -- it didn't jump around or stay in one place. At 2500-2700 rpms, the advance, as measured by the advance timing light, was around 15 degrees. (This matches about what the manual calls for.) As the rpms returned to idle, the mark returned to the beginning position, which was established with 4 degrees advance on the advance timing light. I believe there was an upper limit to the advance at 3500 to 4000 rpms at which it no longer advanced -- but I'm not sure about this.

Before the new springs were installed, the timing mark didn't advance as it should and jumped around some. Very inconsistent.

With the new springs in place and the timing performing as it should, and by physically checking the distributor, my mechanic friend determined that the bushing was not unduly worn.


Neither of us felt that we had "exactly 4 degrees" BTDC but close enough. I'll mention the 8 degrees to him.

I should add that after setting all this by the timing light and "by the book," so to speak, my friend then fine-tuned the timing, idle, and mix until to his ear it sounded right. This is a procedure I can't do because my friend can draw on 30-plus years of experience with these distributors and these cars.

As for knowing how fast the timing advances, all I can say is that my friend said that īt looks right" and īt "sounds right."

Bottom line: the car runs extremely well -- smooth, good acceleration, good power up hills, good smooth idle, no pinging. I don't think I could ask for better performance.

One other observation: Before replacing the springs on the weights in the distributor, I had to keep the idle at 1100-1200 rpms or the engine would become very lumpy and sometimes stall. Once the new springs were in and the timing was finally set properly, I was able to lower the idle to about 800 rpms while maintainning a smooth idle, and may be able to go even lower.

tdskip
05-21-2011, 08:07 AM
Bottom line: the car runs extremely well -- smooth, good acceleration, good power up hills, good smooth idle, no pinging. I don't think I could ask for better performance.



So isn't this time to call it done and drive her? Everything is approximate at this point anyway, right?

LexTR3
05-21-2011, 08:20 AM
tdskip,

You are right. Time to hit the back roads of the beautiful Valley of Virginia... In fact, run well or not, I've been putting on the miles since January. Any day is a good day for a ride... to echo that other adage: Any day above ground is a good day.

However... and there's always a however with me ... now that the timing is correct (or as correct as we can get it), on some rainy day I will probably go through the carb balancing and mixture setting routine again to get it just right.

One more last thought on static timing vs dynamic timing. I have come to the conclusion that a combination of the two is the way to go. Using the static timing method, I can get to TDC. Then, using the dynamic timing method I can advance it four degrees and check the advance at 2500 and 3500 rpms. Thereafter, from time to time, I can use the advance timing light to check on the timing. Does this sound reasonable?

swift6
05-21-2011, 08:48 AM
Ed,

You already stated that your mechaninc friend with 30 plus years experience of tuning these cars already fine tuned your timing, idle and mixture. Why are planning on mucking with it on some rainy day? The only time these cars need CONSTANT tinkering is when everything is worn out. If all the parts are in good shape they can hold their settings for quite some time and many many miles. Don't mess with the carbs or distributor until you notice a change for the worse in your idle, performance, gas mileage etc... Then have your friend teach you how to do it correctly, not just show you.

LexTR3
05-21-2011, 01:21 PM
Hi, Shawn,

You are absolutely right, and it is the advice my mechanic friend gave me (except that he said I might want to continue to fine-tune the carbs until I have the idle as low as possible and the carbs running as lean as I can without running too lean.)

One problem -- and it is a bit of an unknown -- is that about a year ago the guy at shop where I have much of my work done was tryig to tune the car and was having trouble. He didn't check the timing, but worked on the mixture and the idle. When he couldn't get things the way he wanted them to be, he put in new needles in the carbs. (My mechanic friend suspects that the guy took out standard SM needles and put in RH rich needles.) The reason for this suspicion is that my mechanic friend said that he was unable to lean the mix for optimum performance. So, he said that now that the timing is set properly, I might want to inspect the needles and, if they are RH needles, re-install SM (standard) needles. If that is done, I will have to re-set the mixture.

I've gotten pretty good at balancing the carbs and setting the mixture and idle, but I have been hindered by the problem with the timing.

You are right also: once the timing has been set, it should remain good for some time, and once the carbs have been balanced and the mixture set, that should remain good for a reasonable time.

All this comes as somewhat of a pleasant surprize to me however because back in 1962, when I had another 58 TR3, the Carbs had to be adjusted almost weekly, and I was told at the time that "that was normal for these cars." It was a complaint I heard from other owners of cars with dual SU carbs. .... But those were the days when some guys changed the oil in their cars once a week, and many others once a month!

TR3driver
05-21-2011, 06:04 PM
(My mechanic friend suspects that the guy took out standard SM needles and put in RH rich needles.) The reason for this suspicion is that my mechanic friend said that he was unable to lean the mix for optimum performance.

RH needles would not prevent setting the idle mixture to optimum. They are not rich across the range, but only at mid to upper throttle.

If you can't get the mixture down at idle, the most likely suspect is leaking gaskets inside the jet housing, or the jet itself is worn internally. This is a dangerous condition, since setting the mixture "correctly" at idle will result in being overly lean at cruise; which can lead to overheating or even internal engine damage.

I learned that one the hard way back in college. Dad's TR3A had worn jets and the overly lean mixture eventually burned an exhaust valve stem so badly that the head broke off and went through the piston. He said he looked in the mirror and saw a cloud of engine parts, chasing him down the freeway.

The liner came out in pieces, the rod was bent into a "C", but I cleaned up the mess over Christmas break (without even pulling the engine) and it still runs today (or will, if it ever comes home from the body shop).

HerronScott
05-21-2011, 07:09 PM
All this comes as somewhat of a pleasant surprize to me however because back in 1962, when I had another 58 TR3, the Carbs had to be adjusted almost weekly, and I was told at the time that "that was normal for these cars." It was a complaint I heard from other owners of cars with dual SU carbs. .... But those were the days when some guys changed the oil in their cars once a week, and many others once a month!

I don't know about H6's but I do know about HS6's. When my TR4A was my daily driver and my wife's Spitfire was her daily driver back in the 80s, I rarely had to touch them once they were rebuilt and I had them tuned in and both of us put over 75,000 miles on each car.

Scott

LexTR3
05-23-2011, 06:30 PM
Randall,

I have complete rebuild kits for the two jets, which I intend to install as soon as I find the time. (I suspect that the gaskets are worn out in the jets. And one jet sticks a bit.)

In the meanwhile, following your advice, I will not make the carbs any leaner than they are now, and I won't put the new needles in until I can rebuild the jets.