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Tips

1967 Healey 3000 Keeps Stalling

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Oh, NO! You violated the cardinal rule!
You HAVE to change the coil first!


Joke, son, just a joke.

That said, for me, testing the coil in the field when I suspect I have a problem, and no scope, is to locate a spare high tension lead (coil to distributor cap), long enough to reach the upper parts of the engine.
STart the car and get it warm (runs with no choke). Shut it off, pull the wire out of the coil, insert the new one, key on, brakes on, neutral, hold the end of the wire 1/2" from metal, crank with the button, and see how much spark you get, and if it's even, like, "zap-zap-zap-zap-zap".
Put it back "right" and drive it until it quits.
Do the same test, important the amount of spark throw is real close to what you had initially, and that the even "zaps" aren't "zap..............zap-zap..........zap-zap-zap" which indicates a breakdown. You pass that test, it isn't the coil.
 
IIRC, the nominal float valve setting--the gap between the valve fork and the edge of the float bowl cover--is 7/16". By decreasing the 'gap,' you've raised the float levels hence the level of fuel in the jets. For a given (tapered) jet needle height, you've decreased the annular ring between the jet opening and the needle. IOW, you were running way rich and now you're either running slightly rich, at correct mixture or slightly lean. This probably explains your stalling. At idle, especially, your engine was 'loading up' with unburnt fuel, to the point the mixture couldn't support combustion (this is also why your idle drops off on hot days--the less dense air causes a somewhat rich mixture).

The float levels are critical adjustments--they should be set to the correct level and the jets adjusted accordingly. If not, you may have other drivability issues; e.g. poor mileage or lack of power. Take the vacuum chambers ('dashpots') off the carbuettors and check the jet height. The top of the jet should be about 1/16" - 1/8" below the top of the jet bridge. I wouldn't be surprised if yours were close to level with the bridge or even above, which could be a problem if the pistons have peened the tops of the jets.
 
Thanks TDC and Bob.

As for jet height, I do see how they are presently below the jet bridge up to about 1/8" (both do not appear to be at exactly the same depth, but both are below and is approximately 1/8"). I never touched their position.

BTW, can anyone post pictures here? I can make sketches and so to fully understand something, I would like to know in more detail and by drawing it (or photograghing it). This might help me to better understand.

I've also kept a journal from day one with sketches and notes, and so if I can offer how to, say, rebuild a generator or other tricks I know, then I wonder if it would be okay (and only if the question came up, of course).

If so, then maybe one could guide me how to post here??.

Just a thought.

Thanks!

Paul
 
Did you check the position of the needles in the pistons? Some needles supposedly came with a shoulder that should be just covered in the piston, but all the needles that I've seen have a circumferential groove to indicate depth. The needles should be inserted into the piston so that the bottom of the groove is flush with the bottom of the piston. Not knowing the correct procedure, I set my needles to the top of the groove and adjusted the carbs. The car ran good, but eventually I learned the correct 'technique' and set the needles at the correct depth. The grooves are very small--probably less than 1mm wide--but this made a big difference in the way the engine ran. I was now running too rich. When I adjusted the mixture correctly all was well.
 
Thanks Greg about posting pictures. I will look into that.

Bob, When I get to moment to figure out how to post pictures, I can show you exactly what I did with the needles.

What still bothers me now, learning from other folks, is the float level settings I had may of been set correctly before I adjusted them. They were set at about 1/2" or slightly so and I reduced it to about 5/16" or slightly more. So now I am very cautious and confused as to why I was able it drive the car for 25 minutes without it stalling out.

I will keep going with checking and improving the easy areas anyway from the list I put together and hope for the best!

Thanks again!

Paul

PS - Bob, I reread your thread about the float levels, etc. Sorry, I didn't absorb all that before, especially about the carbs now possibly running a little leaner or richer. I guess I will have to just keep tinkering and hope I find to right markings, settings, etc.
 
I use www.photobucket.com to upload photos. They have an editing function which allows adding text boxes etc. You then can copy the image info and paste into the forum post.
 
Was the car stalling on hot days but not on cold (warm air effectively enrichens the mixture)?

Float level should be set by a 7/16" gap between the straight 'shank' of the forked lever and the bottom edge of the float bowl cover (a 7/16" drill bit works well for this adjustment). Half-inch would have been too low a float level, resulting in a rich(er) mixture. It's also possible--if the level is too low--for a needle-type float valve to cock sideways and jamb, resulting in flooding.

Once the float level and needle depth are set correctly the mixture is set by raising or lowering the jet. If everything else is correct, the top of the jet will end up 1/16" - 1/8" below the top of the jet bridge. If not, something is wrong somewhere (or mixture isn't set correctly).
 
Bob,

Hopefully today, I will have a chance to look over the float settings and jet heights. I "think" I am getting a better hang of what is needed to be done to tune the carbs up.

I will remove the float chamber covers again, readjust the float levels to 7/16", make sure the gross jets are opening and closing properly, then remove the piston chambers and examine the jet heights, (maybe I should establish new bench marks on both by having each jet adjusted to about 1/8" below the jet bridge??). Then take it from there and see what happens.

Right now, on cold starts, she wants to stall out real badly, backfiring a lot, too (popping with real flat acceleration). At the moment, I am blaming that on the timing (and/or maybe the vacuum advance as well??). After the engine warms up, the car behaves tame enough where I can drive it without it stalling out. I also hope I can find the timing mark. If not, then for now, I will use Keoke's proposed idea of averaging the distributor by swinging it to opposite extremes, then average out the distance and add a notch to get close to the 10 degree BTDC (I hope that is the desired degree setting).

I will let you know how things turn out.

Thanks!!

Paul
 
Sounds like the choke needs some attention to.---Keoke
 
Legal Bill said:
I doubt it was the float adjustment. I'm voting for the fuel filter
Click to expand...


------------- :thankyousign:


-------------- :iagree:----------------------------Keoke- :laugh:
 
Legal Bill and Keoke,

You might just be right. Today, a friend and I looked over a few things.

First we tested the voltage output of the generator. Then located the timing mark (hooray and about time).

Then we noticed 2 things about the newly installed clear gas filter by the SU's. It has evidence of some debris inside already and there is the presence of air visible inside the filter (more so today than when I installed it on this past Friday). My friend feels the fuel pump should of had enough pressure to force out all the air. Is he correct to say that? The debris must be eminating from the gas tank or even debris found in the fuel pump.

BTW, our findings of the generator is as follows: While in normal idle, voltage output was registering at 0.6 volts. After revving a bit, it registered as high as 1.8 volts. Then we tested the charge of the battery and that was at 12.0 volts. The same goes for most connections of the voltage regulator. I believe three of four registered 12.0 volts, the fourth at 0.0 volts (I can check this again). I believe the voltage output from the ignition coil registered also at 12.0 volts. I explained to my friend that if he had any doubts as to why some readings may be low (as well as why the ignition light remains lit--besides a short existing somewhere), that it may be because of this conversion process not being complete, due to the change of negative from positive, plus things like the cut off switch not hooked up, and the tach not working (but am I making real sense here?!).

She still drives along without stalling. SO far, that's good, but I will go back and makes adjustments. Another "btw", the so called "slow idle" screw, is it always the rule to turn it 2 1/2 turns and then leave it alone??

Thanks again, as always.

Paul
 
Hi GregW,

"Flash" is a term I am hearing for the first time (that shouldn't surprise you). I have heard the word "spike" and applied that principle when I rebuilt the generator (bearings) and also applied some "liquid tape" to exposed wring which is what I assume serves as a bridge between the outer wire wrappings (on the inner housing part).

The ignition light has always remained dimly lit from day one when I bought the car. So for the moment, I am assuming it is a short relating what I mentioned above or certainly not the generator, unless one tells me otherwise.

After the generator was reinstalled, I spiked the larger of the two connections (I assume that is the positive), before attaching. The smaller wire connection was left connected.

I hope that is what you mean by flash. Do my voltage results sound okay? I never had a problem turning over the engine since a new battery was installed.

Thanks,

Paul
 
To flash or repolarize the generator, Norman Nock gives the following direction:
disconnect the wires from the D and F terminals on generator. Connect a length of wire to positive terminal of battery and touch the other end of wire to the small (F) terminal on generator briefly several times. Reconnect wires to D and F terminals.

The voltage of a fully charged battery should be 12.5 to 12.7 volts. I don't think your generator is charging. A new battery will start the car until it looses about 25% of it's charge. You should buy Norman Nocks tech tips from British Car Specialists.
 
TimK,

Thanks for the knowledge about how to flash the generator. Any minimum size (gauge) wire needed to do this flash process properly?

I will check again what the voltage output is for the battery. When we tested the battery, it registered 12.0 volts at idle. Just curious, if the voltage increased as a result of revving the engine, would this suffice that the generator is functioning as it should? I have had this "new" battery in for about a month and cranking away, letting it idle for hours and now driving it around town. Wouldn't any new battery go dead by now after that?

I will certainly look into this Norman Nocks tech tips you suggested. Thanks for that, too.

Much appreciated!!

Paul
 
I will let Keoke answer about voltages. I have not tried to measure generator voltages, I have an ammeter which measures amps. I get 15 amps at startup briefly to top up the battery. The regulator controls generator output. I don't know how the voltage changes with engine speed.
Any 14 gauge wire should do.
 
TimK said:
The voltage of a fully charged battery should be 12.5 to 12.7 volts. I don't think your generator is charging. A new battery will start the car until it looses about 25% of it's charge. You should buy Norman Nocks tech tips from British Car Specialists.
Click to expand...

:iagree: 12.78 volts on a fully charged battery. If you see
12 volts that means you have a problem especially after running the car for a while.
If you look in the maintenance manual, ( you should buy one since you are trying to do it yourself ), you will find how to check the output of the generator. If I remember you should see
15 to 16 volts output when the engine is reved.
If you see the little red light on all the time, then the combination of the generator and the voltage regulator is not charging. If your battery is good but only shows 12.0 volts ,
then it is already discharged quite a bit.

There is a little black ground wire leaving the bottom of the voltage regulator that should be fastened to the firewall along with a couple of other black ground wires. The paint surrounding the hole in the firewall where that screw fastens MUST be scraped free of paint and a star washer placed between the firewall and the ground wire lug that is next to the firewall. A lot of folks don't want to do that after getting a shinny new paint job. Without the proper ground connection to the voltage regulator it will not charge and the red light will stay lit. Of course if the generator is not putting out voltage then you will get the same result. Use the manual and check the output as directed to determine if the generator or the voltage regulator is the cause of your low voltage.

Happy hunting,
Ed

:hammer:
 
Another good way to check a coil is with an ohmmeter. Put the leads across the primary side of the coil and you should have close to three ohms ( disconnect all of the wires from the coil first ). The farther off from 3 ohms, the more likely the coil is shot. If it checks ok when cold, Drive the car until the backfiring starts and then pull over and check it right when the car is acting up.
If you see signs of goo leaking out of the coil down onto the generator case then there is a good chance the coil is shot.
...
I am not saying the coil is YOUR problem but just explaining another way to check it.

Ed
 
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