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Tinster
06-29-2008, 07:44 PM
I'm still trying to get my car streetable.
Multi part question:

Do distributors fail suddenly and leave you stranded?
Or do distributors fail gradually and give you warning?

Is there a diagnostic procedure to test the viability
of a distributor? How can I determine if my distributor
needs to be rebuilt?

Do bad distributors burn up condensor cans?

thanks,

dale

TR3driver
06-29-2008, 08:12 PM
Never seen an LBC <span style="font-weight: bold">distributor </span>fail suddenly ... but since I don't trust my electronic ignition, I keep a fully loaded distributor (complete with adjusted points, condensor, cap, rotor and wires) in the center of the spare tire. It's both a source of spare parts, and an easy swap if the electronics module dies (or even becomes suspect) far from home.

Main things to look for are excessive play in the shaft/bearings; and proper operation of the centrifugal advance.

Both can be investigated with a timing light. If the timing mark seems to jump around under the light, the dizzy is worn. As you slowly rev the engine from idle to about 3500 rpm, the timing should smoothly advance. (I forget offhand where it stops advancing for a TR6; likely the value depends on which year dizzy you have.) Then let the rpm drop slowly, and watch the timing go back to it's idle value. If it starts jumping around, or suddenly changes, or doesn't change, there is a problem with the advance mechanism.

As a final check, hook the light up to #6 instead of #1 and check the timing again. Should be exactly the same; if not you may have a bent shaft.

Brosky
06-29-2008, 08:14 PM
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Do distributors fail suddenly and leave you stranded?[/QUOTE] No.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Or do distributors fail gradually and give you warning?
[/QUOTE] No.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Is there a diagnostic procedure to test the viability
of a distributor?[/QUOTE] No.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]How can I determine if my distributor
needs to be rebuilt?[/QUOTE] Please review your credit card receipts. Jeff just rebuilt it. It's fine.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Do bad distributors burn up condensor cans?[/QUOTE]

No, but condensors can suddenly fail without warning because stuff just happens.

It is time to drive the car...............

swift6
06-29-2008, 08:18 PM
I've never seen a distributor fail suddenly either. Points close yes, condensor fail yes, but nothing else on a distributor fail suddenly. The pin for the drive gear can shear, which would be sudden, but for that to happen there would be a whole lot more going wrong suddenly in the engine internals. Which I HIGHLY doubt is happening. It usually takes many, MANY more miles than you've put on Amos to wear a distributor out.

swift6
06-29-2008, 08:23 PM
It is time to drive the car...............

:iagree:

If your still unsure of Amos' trustworthiness, drive progessively farther with each drive to build your confidence and shake out anymore bugs from what is left, or not left, of Cryptie.

First drive, MINIMUM of FIVE MILES! No more around the block, unless its five miles around the block.

On your next drive double that to ten miles minimum. Double the next one to 20 miles minimum. Keep going until you find the car trusty enough to no longer think about it. Go drive it and enjoy it.

Tinster
06-29-2008, 09:07 PM
"If the timing mark seems to jump around under the light, the dizzy is worn"

<span style="color: #990000">That is EXACTLY what I see.
I tried reversing the clip-on for wire No. 1
and still got the bouncing, jumping timing mark.

The shaft inside the dizzy does NOT wobble.

I'll try the experiment with wire No. 6

I did have the Petronix but it died in under
200 miles. I got just about 1,000 miles from
the condensor.

Maybe Jeff needs to rebuild it again?

thanks,

dale</span>

Brosky
06-29-2008, 09:28 PM
Before you jump to any hasty conclusions try a different wire on the number one spark plug and check the readings again.

Have Wendy hold the throttle steady at 1,000 - 1,500 - 2,000 and 3,000 PMS and observe the readings on each. Then post back.

This would be AFTER you put about 20 well run miles on the car to blow out all of the carbon from the garage cruising.

tom628
06-30-2008, 01:04 AM
Dale, if you have the points back in you may find that you do get more timing lite fluctuation with the points than with the Pertronics installation. But, if you're not used to looking at this stuff, you may be exaggerating the problem. It's almost certainly not going to stop the car dead in its tracks.
There have been some rotor failures and condenser failures. If you don't feel confident, carry a couple of each with you when you take it for a ride. But, as others have said, make it a good ride so that everything gets up to temperature, the cobwebs get blown out, etc.
Good luck,

Tom

KVH
06-30-2008, 02:39 AM
Tinster, if the shaft isn't wobbling, I'd check a few other things.

First, of course, make sure you have a good rotor and that your points are set correctly.

One thing that will go "suddenly" is a distributor cap. I had it happen twice (different cars), and the second time I was too stubborn to suspect it. I had my car towed when all it needed was a new cap. There's something about the conductors and the rotor interplay that can make them "go" when they reach a critical point of wear. I doubt your cap is the problem here.

I'd check the wires as others have said, and I'd also check your carburetor shafts. If they suck air, your idle speed will be uneven and that can cause that timing mark to act irradic as well. Proper carb shafts and bushings make a big difference.

If the carbs are set right and aren't sucking air, I'd reset the points, time it, and check it with a light. I can't recall if your car is static timed or not, but you can check it with a light in any event.

I'd not suspect the distributor unless there's something obviously wrong from a visual examination.

What did you do about the gas tank? And domestic pacification?

Good luck.

DrEntropy
06-30-2008, 05:00 AM
With the rotor firmly in place, move the thing back and forth by hand and observe whether or not it has movement past where the mechanical advance stops the shaft. IOW, as you turn it the "stop" on the plate will halt the shaft, but the rotor may travel further. If so, the rotor has wallowed out and needs replacing. Otherwise, drive the thing.

If Jeff's been thru that diz there's NO NEED to fret over it for YEARS. The points can wear, that's why they're adjustable/replaceable. Condensors the same. They're both small, inexpensive and fit in a glovebox...

Cap and rotor are asked to do a demanding job and can "fail" but usually there's a lot of warning. Post pix of the inside of the cap and the shaft socket of the rotor.

...don't MAKE me come over there. :devilgrin:

dklawson
06-30-2008, 07:01 AM
I'd like to direct you back to the comments of Kentvillehound and Randall about timing scatter/bounce and carbs.

Though intuition tells you that the carbs will have no effect on timing... look carefully again at your carb adjustments. You may find that after as much major work as you have undertaken you need to go through an iterative tuning process where you start with the "basic" carb settings and the default ignition timing, then adjust each a little while paying close attention to the carb balance and mixture. I have seen timing scatter on engines that persisted until both the timing AND the carbs were adjusted. Once the mixture was really right and balanced the timing became very, very, steady. Intuition and logic tells you this shouldn't happen but I've seen it before.

As for condensers burning out... it does happen but I can't think of a reason why it would be in any way associated with a worn dizzy. I haven't been following all the threads here so forgive the following question if it repeats what's been covered in previous threads. You do have the correct coil for your ignition type don't you?

Tinster
06-30-2008, 06:33 PM
Dale, if you have the points back in you may find that you do get more timing lite fluctuation ...make it a good ride so that everything gets up to temperature, the cobwebs get blown out, etc.
Good luck,

Tom

<span style="color: #CC0000">So OK!

I took the Crypt Car out and performed the EYE-tal-yun
tune up, as suggested. 1 hr and 50 minutes drive time should
have blown out some carbon.

Now, I'll next perform the timing light diagnostics and post
back with findings.

thanks one and all for your generous help and suggestions.

This car is getting closer and closer to being streetable.

yup! :yesnod:

Dale</span>

DNK
06-30-2008, 06:35 PM
Ya drove it on the Street today dinja. Then it's street able.

Tinster
07-01-2008, 07:50 AM
Continuing with sorting out the carbs and ignition:

I pulled the No5 cyclinder plug this morning and
this photo is what I found. I know there are plug
images for comparison but what can the Triumph experts
tell me from looking?

Also a small question: Where is engine vacuum tested?
I attached my vacuum meter to the intake manifold nipple
that goes to my brake canister. Is this correct? I got 20.

thanks, dale

https://i134.photobucket.com/albums/q101/TinsterTR6/plugsNew2.jpg

TR3driver
07-01-2008, 08:17 AM
That plug looks fine to me. Just perfect, considering that your driving is mostly low speed, short trips.

Vacuum gauge can be connected anywhere there is manifold vacuum; the nipple for the brake booster is fine. 20" and steady is also fine. There's a nice chart of vacuum readings and likely causes at
https://www.classictruckshop.com/clubs/earlyburbs/projects/vac/uum.htm

Tinster
07-01-2008, 08:28 AM
Wow, Randall-Thanks!!!!

I had no idea such a graphic chart existed.
What a great diagnostic tool.

Now off to the Doc's.

d :thumbsup:

Mickey Richaud
07-01-2008, 08:32 AM
ALL of our plugs should look so good!

Brosky
07-01-2008, 08:52 AM
Please remember that a camel was once a great race horse until engineers got their hands on it. Read as over analyzing.........

Stop looking for problems and drive the car. It's the best medicine for you and the car.

dklawson
07-01-2008, 11:18 AM
This is a general question related to Tinster's.

None of my LBCs have had the vacuum advance/retard distributors, they have all been advance only. Those connected to a venturi port on the carb for ported vacuum, not the intake for manifold vacuum. So... when did BL introduce the advance/retard distributors?

TR3driver
07-01-2008, 12:28 PM
The vacuum retard was introduced around 1968, in response to new emission control requirements. The dual advance/retard was only used for a few years, then they went to retard-only.

Some cars didn't have vacuum retard but instead extra mechanical advance, so the idle timing could still be 4 ATDC but it would advance to the normal range once the engine was revved to operating rpm.

In theory, the retard at idle helps lower HC (unburned hydrocarbons); while the lack of vacuum advance helps lower NOx (nitrogen oxides). But better methods were found to control both of these pollutants later on, so it was only the 70s engines that were saddled with such poor compromises.

Silverghost
07-01-2008, 01:03 PM
Wait.....wait......WAIT!! Did I read that correctly??! An HOUR AND 50 MINUTES of drive time??! HOLY GAS PEDALS, BATMAN!!!! &lt;sniffs smelling salts!&gt; Ok, ok....first, call NBC, then CBS, then ABC....get Oprah on the phone! That's some of the best news I've read from Dale in a while! I DO so hope I read that correctly!! :laugh:

Tinster
07-01-2008, 02:29 PM
Wait.....wait......WAIT!! Did I read that correctly??! An HOUR AND 50 MINUTES of drive time??! HOLY GAS PEDALS, BATMAN!!!! &lt;sniffs smelling salts!&gt; Ok, ok....first, call NBC, then CBS, then ABC....get Oprah on the phone! That's some of the best news I've read from Dale in a while! I DO so hope I read that correctly!! :laugh:

<span style="color: #990000">Yup, Peter!! Indeed you are reading it correctly.

All time daily record for year-to-date 2008 at 73 miles.

67 miles total driven in 12 months of year 2006

Year 2007 record (unknown by most) 5 hours @ 170 miles driven
during one day I lost the Crypt Car demon in the mountains.

dale</span> :thumbsup:

Tinster
07-01-2008, 02:57 PM
OK! Paul, Doc, Randall, et al - Dizzy Timing Test results!
Requested photos below text- Any and all coments are
appreciated to help finally sort out the system(s) bugs..

Dale :cheers:

Both ears on distributor plugged off
Both vacuum lines on carbs plugged off
Car engine warmed to 160*, smooth idle at 700 rpm
&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;
<span style="color: #990000">Cylinder No. 1 wire hookup
0700 rpm..........at 10* BTDC advance
1000 rpm..........at 18* BTDC advance
1500 rpm..........at 24* BTDC advance
2000 rpm..........at 27* BTDC advance
2500 rpm..........at 27* BTDC advance
3000 rpm .........at 30* BTDC advance

Observation: timing arrow steady as steel on
the timing mark from 1500 rpm and higher</span>

<span style="color: #000099">Cylinder No. 6 wire hookup
0700 rpm..........at 10* BTDC advance
1000 rpm..........at 17* BTDC advance
1500 rpm..........at 24* BTDC advance
2000 rpm..........at 27* BTDC advance
2500 rpm..........at 27* BTDC advance
3000 rpm .........at 30* BTDC advance

Observation: timing arrow steady as steel on
the timing mark from 1500 rpm and higher
</span>

https://i134.photobucket.com/albums/q101/TinsterTR6/dizzyCap.jpg

My new distributor cap has 183 miles on it. It arrived from
the vendor broken as shown but seems to work OK.

https://i134.photobucket.com/albums/q101/TinsterTR6/dizzyRotor.jpg

My new rotor has 183 miles on it and is matched to the new cap

https://i134.photobucket.com/albums/q101/TinsterTR6/dizzyGuts1.jpg

My advanced Distributors dizzy has about 1700 miles, the points
have about 1500 miles and the condensor can has 74 miles on it.

I reinstalled the two vacuum lines when the timing testing was completed.

&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt; &lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;,

I also performed intake manifold vacuum testing today.
Here are my results: My carbs and manifold have 1700 miles.
Jeff Palya's all components.

https://i134.photobucket.com/albums/q101/TinsterTR6/vacgauge.jpg

A warm idle, steady as a rock at 19 inches- no flicker at all.
A rise to 24" at 2000 rpm and then a uniform downward flow to 19 inches but NOT instantly back to 19". I have a 6-3-1 header.

https://i134.photobucket.com/albums/q101/TinsterTR6/manifoldVacuum.jpg

DrEntropy
07-01-2008, 03:08 PM
This is ALL good news, Dale. All 'cept th' broken cap bit. Non-critical, tho. Jus' don't go charging thru any standing water at speed. :wink:

From the dizzy photo I may make one eensie suggestion: see if you can coax the bare ground wire away from proximity to the lead goin' to th' points from the white connector. It makes me nervous.

Thanks.

Silverghost
07-01-2008, 03:33 PM
I noticed the ground wire too. Do I detect a bit of rust, er, I mean corrosion at the screw and possibly along the wire in addition to what you saw, Doc? Other threads have mentioned this ground wire as a potential cause of woes. I am not trying to fix something that's not broken, just making an observation.

Silverghost
07-01-2008, 03:36 PM
WOO HOO!!! Dale, I am sending an email to Mayor Daley to see if we can get you a parade!! :laugh:

DrEntropy
07-01-2008, 03:42 PM
Surface rust on that screw, naught to worry over. More concerning is the ground's proximity to that points trigger wire.

Tinster
07-01-2008, 04:04 PM
Surface rust on that screw, naught to worry over. More concerning is the ground's proximity to that points trigger wire.

<span style="color: #006600">Bloody Ground Wires!

They have been a curse on this car since day one!

I use this green goo stuff on all the electrical connections of
my boat and wiring of my trailer. The green goo dries into a water
tight plastic.

Should I green goo the ground wire and points trigger wire?
It would be easy.

d</span>

Brosky
07-01-2008, 04:15 PM
One or two minor issues as outlined in two previous posts and get in the car and drive it.

angelfj1
07-01-2008, 04:19 PM
Dale: just drive the car and PLEASE don't adjust anything. :nonono:

Brosky
07-01-2008, 04:20 PM
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Should I green goo the ground wire and points trigger wire? It would be easy. [/QUOTE]

Dale,

It has made it 38 years without the green goop. Just clean it up and don't start putting stuff in there.

Also, add two drops of 3 in 1 oil down inside the distributor shaft, on the screw under the rotor, if you haven't already done so lately.

TR3driver
07-01-2008, 04:27 PM
Remind me again ... were you actually trying to fix a problem here ? Cuz I sure don't see much of anything wrong with all above; certainly not enough to cause problems.

The spark scatter at idle might be the light itself, or possibly too much end float in the distributor drive gear; but it doesn't sound like enough to worry about. My TR3A dizzy IS worn, and has lots of scatter, but runs fine.

The 'hitch' in the advance curve is also a bit odd; but again is most likely an artifact of your timing light and won't cause a problem even if it's real.

So, quit tinkering and drive it!

Remember to keep the oily side down
:driving: :driving: :driving:

Tinster
07-01-2008, 04:29 PM
Dale: just drive the car and PLEASE don't adjust anything. :nonono:

<span style="color: #990000">Hey Frank!

It would APPEAR I have things properly adjusted as are.
How'd THAT happen? :rolleyes:

But I am wondering something. The bottom of my distributor
(the dog?) is out by 180 degrees and thus so are my spark
plug wires. If cylinder No1 and No6 both fire at 10* BTDC
can I simply switch out the two wires on the distributor cap
and have a "normal" looking distributor cap?

d</span>

<span style="color: #3333FF">Randall, yes I was trying to get the car operational
at rpm over 1500. To refresh the memory, the engine would idle
but fall apart and stumble over idle speeds. I rebuilt the fuel delivery
system. Then installed a condensor and today tested the dizzy. Tomorrow
I will street the car again.

d

d</span>

TR3driver
07-01-2008, 04:53 PM
If cylinder No1 and No6 both fire at 10* BTDC
can I simply switch out the two wires on the distributor cap
and have a "normal" looking distributor cap?<span style="font-weight: bold">NO !</span>

In addition to the piston being near TDC, the valves must be closed when the cylinder fires. But when #1 is firing, the valves on #6 are open, and vice versa.

Whatever is causing the breakup above 1500 rpm, it doesn't appear to be the distributor; at least not the low tension/timing portion of it. Might be a high tension problem, but I think fuel is more likely.

eejay56
07-01-2008, 04:57 PM
can I simply switch out the two wires on the distributor cap
and have a "normal" looking distributor cap?

Dale,
NO, it goes intake,compression,&lt;spark&gt;power,exhaust
if you did that 1 and 6 would be firing between exhaust and intake. That would be bad.

Brosky
07-01-2008, 05:08 PM
Dale,

Remember that the crank turns twice for every turn of the cam. Four cycle requires that the pistons go up and down twice to complete the process which is two revolutions of the crank, but only one of the cam as the intake and exhaust open at different intervals of the 360 degree cycle.

Please......take the advice given above and stop tinkering and just drive a nice running car.

martx-5
07-01-2008, 05:44 PM
NO, it goes intake,compression,&lt;spark&gt;power,exhaust


It's easier to remember ... suck, squish, bang, whoosh! :laugh:

Of course a 2-cycle is just bang, whoosh, bang, whoosh.

TR3driver
07-01-2008, 06:13 PM
Or as I learned it : Suck, Squeeze, Pop, Fooey

dklawson
07-01-2008, 06:53 PM
Randall, thanks for the explanation on the advance/retard distributors. I'll be picking up our "new" '72 Spitfire this weekend and I assume from your information I can expect it to have such a distributor.

Dale, I wouldn't apply any insulating coating to any of the components in the dizzy. What all of us seemed to notice was the bare wire from the dizzy housing to the breaker plate runs very close to the end of the points trigger wire where it passes out of the distributor. Just re-route the breaker plate ground wire a little to avoid the trigger wire. As for the screw corrosion, a little ScotchBrite and the application of some dielectric grease or Vaseline to the cleaned surfaces will help without locking things permanently together.

Brosky
07-01-2008, 06:58 PM
Amen Doug, Amen.

Now you can drive it!!!

TRDejaVu
07-01-2008, 07:40 PM
or Suck, Squeeze, Bang, Blow as I learnt it.

startech47
07-01-2008, 09:12 PM
The slotted tab with the screw holding the condenser to the movable breaker plate needs to be moved slightly towards the center of the distributor to prevent the tab from rubbing on the inside of the distributor housing and perhaps limiting breaker plate travel if the vacuum advance is used.

Silverghost
07-01-2008, 11:01 PM
Dale, mine was just an observation. Follow the others advice about the proximity and get three hours of drive time tomorrow! Still working on that parade and waiting a return call from Oprah! :wink: