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Tinster
09-26-2008, 07:47 AM
Some more curiosity question1.

1. Has anyone moved their ignition coil
off the engine block to a location not
so hot?

If so, I'd like to see a photo of the new location
for the coil.

,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, ,,

I have the single piece, 1969 air filter with
the twin opening pipes in the front of the unit.

2. Has anyone ever installed hoses onto these two
stubby pipes and then run air hoses into the fan shroud
interior area? I am thinking this would provide cooler air into the carbs.

Photos would be real helpful.

thanks,

dale

KAllen
09-26-2008, 08:06 AM
Hi Dale;

I have enjoyed your write-ups on your TR6 - sorry to hear you continue to have issues. I live in SW Florida (Cape Coral - near Ft. Myers) we have fairly similar weather. 3 significant changes to my 73 TR6 has eliminated the bulk of problems.

1) Replace the distributor with a 123 electronic ignition. Its totally electronic. No condenser to fail - only problem - it will not run your mechanical tach. I have had NO starting issues since the change. And my coil is on the motor - and used to give me issues too - not anymore.

2) Install a shroud on the inside of the radiator. I wrote about mine last week. Its a toyota truck radiator shroud. Plastic and with just a few cuts it screws on - you get much better air flow and if you want - can eliminate the cardboard front shroud for better engine bay breathing.

3) Replace the carbs with Mikuni's - they are amazing by comparison to the strombergs or su's. It will require a cable accel. linkage similar to Rat-co's setup. But the do not get vapor lock - they have stunning response and get better mileage.

#1 and #2 are cheapest. The 123 distrib. was about 400 bucks. and the shroud was under 20 bucks. The carbs are just under 800.

vivdownunder
09-26-2008, 09:37 AM
I widened out the coil bracket and inserted a strip of rubber of about 2mm thickness as an insulator between the coil and the bracket. This cut engine temperature transfer to the coil quite a lot, yet kept the car original looking.

DNK
09-26-2008, 10:21 AM
dale Mine will be mounted on the fender where our relays use to be. The Ign. box will be in front of the wiper motor which is another common area to remount the coil.

tomshobby
09-26-2008, 10:36 AM
Over the years I have driven 3 different triumphs, 1964 TR4, 1967 GT6, and now our 1976 TR6, for a total of about 150 thousand miles. I have never had a coil problem of any kind with the original coil in the original location.

RonMacPherson
09-26-2008, 11:56 AM
I mounted my coil up on the engine compartment side of the drivers footwell by the wiper motor. Just need slightly longer coil wire is all.

TR6oldtimer
09-26-2008, 01:10 PM
Over the years I have driven 3 different triumphs, 1964 TR4, 1967 GT6, and now our 1976 TR6, for a total of about 150 thousand miles. I have never had a coil problem of any kind with the original coil in the original location.

Same here. On the TR4 the only electrical problem I had was the generator, and on the TR6, once the distributor ran dry and started screeching, a couple drops of oil off the dip stick got me home.

Tinster
09-26-2008, 06:31 PM
Thanks all !!

Some good ideas. My electronic ignition failed
almost out of the box so I'll stick with points
for now.

I'll post a photo after the install.

Can't afford new carbs- mine are rebuilt and good.
I installed a custom made radiator shield.

I was wondering about putting hoses on the air
inlet pipes and taking them thru the shield.

regards,

dale

Brosky
09-26-2008, 07:39 PM
Dale,

I hate to say this and don't take it wrong, but I thought that you just said the car ran great for a whole day of driving. Why the tinkering?

The hoses will bring a bit of cooler air in, but probably not worth the effort. Even the best Ram Air systems of the 60's only worked well on cool days and at very high speeds.

The coil should be fine where it is. I agree with Tom. My original was fine, but looked crappy when I redid the engine compartment a few years ago, so I replaced it. I still kept it as a spare and it is 34 years old. And the replacement is fine where it is.

RonMacPherson
09-26-2008, 09:21 PM
His idle speed changed, increased, from what he emailed me. Sounds like the warm up compensators need adjusting. I referred him to go to the buckeye site and read up. He should be able to get them in spec.

poolboy
09-26-2008, 09:55 PM
I'm not so sure that the temperature compensators have that much of an effect. When the carb is cold, all the air entering the carb passes over the bridge. When the carb warms up enough the temperature compensator valve opens allowing whatever air that can enter a 1/4" diameter opening on the flange for the air box attachment.
That air actually enters the mixing chamber, but bypasses the bridge and the jet. There is no venturi affect from this air resulting in a slightly leaner mixture reaching the combustion chambers.
I've manually closed an open compensator valve and found it difficult to detect any difference in engine speed.
My guess is that it could be determined by a CO sensor, but not easily by ear or tach.
Then again there's always the exception to the rule and I imagine that how well the initial carb mixture is set may make a difference, too. If the mixture is lean to begin with, the open valve may tend to starve an already lean carb.
But hey, who runs their carbs lean anyway ?

RonMacPherson
09-26-2008, 11:59 PM
Poolboy, what he was talking about is well within the range the temp compensator leakage, or maladjustment can cause. I hope he goes to the buckeye site and pulls it down. They have a very informative section(teglerizer.com helps too) on the Stromberg carburetors. In case you haven't researched it lately,

https://www.buckeyetriumphs.org/technical/Carbs/CarbsIII/CarbsIII.htm

I think it is very helpful...

poolboy
09-27-2008, 07:40 AM
You bet, I've been there and revisit it from time to time. I've learned a lot there.

BobbyD
09-27-2008, 08:01 AM
Maybe I'm wrong but.......doesn't a coil that's too hot to touch indicate an electrical/ignition problem somewhere? When I was having those problems many years ago my coil would get so hot that you really couldn't touch it for very long. And the hotter the coil got, the more the car backfired, stumbled, missed etc. Once the problem was resolved, the coil got quite warm but never really hot. Even now I can drive the car for hours down the highway and the coil, while warm, never gets very hot and it's mounted in the stock place on the engine.

Tinster
09-27-2008, 08:34 AM
Ron,

I've been using the Buckeye documents for some time.

I am fine with everything except the

"bypass ajustement valve" ............

I have not a clue where this valve might be located.

d

DNK
09-27-2008, 10:55 AM
On the rt side of each carb. It's the long rect. thing

TR3driver
09-27-2008, 11:21 AM
There were several different bypass valves, and not all of them had adjustments. But I don't think any of them could be described as "rect." ... perhaps you are thinking of the temperature compensator ?

TR3driver
09-27-2008, 11:27 AM
Here's another photo from Nelson, of the early non-adjustable bypass valve.

The temperature compensator is that yellow thing just showing at the left edge of the photo.

Brosky
09-27-2008, 11:40 AM
If that coil is getting really too hot to touch, that sounds like a ground problem that Dale had in the past that I thought was resolved.

RonMacPherson
09-27-2008, 12:49 PM
Okay Cuz,

When you are on the Buckeye site, skip back to carb part 1, description and theory of operation and disassembly. About halfwaydown just before they get into removing the mixture screws you will see the bypass valve.

I thought it was buckeye that talked about adjusting them, if not, perhaps Teglerizer or VTR. But I know I have seen diagnosis and adjustment procedures on the web.

Maybe someone here can remember where it was and refer to the url?

poolboy
09-27-2008, 01:50 PM
Here's another photo from Nelson, of the early non-adjustable bypass valve.

The temperature compensator is that yellow thing just showing at the left edge of the photo.
That round brass object that you see where the adjustment screw would have been on the "adjustable" versions is a tamper-proof seal. If you pry it off you can "tamper with a small adjustment screw.
There are 2 sympyoms of a problem with the Throttle Bypass Valve that I am aware of.
The first symptom would be failure to return to your preset idle speed in the normal fashion.
This is caused by one or two things. The diaphram surrounding the actual brass valve has a leak or has become too brittle to flex. Or the adjustable spring tension on the valve is inadequate to completely close the valve when you decelerate or stop.
The second symptom is backfiring in the exhaust when you decelerate. That happens because the Throttle Bypass Valve is not opening. That is usually due to too much adjustable spring tension on the brass valve.
A good starting point would be to turn the adjustment screw Clockwise all the way until it stops. Then make 7 Counterclockwise turns.
Test drive, check for backfire on decelerations and proper return to idle. Adjust as needed. Make small adjustments (1/2 turns) from this point on, inbetween test drives.
Keep in mind that if the diaphram (the diaphram around the brass valve) is torn or brittle there will be nothing else to do except replace it (Moss # 365-745) or eliminate it's function by blocking the actual bypass port that the valve regulates and take your chances with the backfire issue.

DNK
09-28-2008, 12:42 AM
There were several different bypass valves, and not all of them had adjustments. But I don't think any of them could be described as "rect." ... perhaps you are thinking of the temperature compensator ?

My bad