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Help with adjusting carbs

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I don't think the dizzy has been changed. Could possibly the vacuum advance be changed but kept with the original distributor?
 
BrandonBJ8 said:
I don't think the dizzy has been changed. Could possibly the vacuum advance be changed but kept with the original distributor?
Click to expand...

Yes, that is a possibility. However, it is now necessary to quote the number on the DIZZY's body to be sure. It should be: 40966 With a letter designation following that number. Check it out and let us know what you find.--Keoke
 
Dave -

Thanks for clarfying that. I had momentarily forgotten that on all healeys the vacuum pick up is on the throttle body, not the intake manifold.

Brandon - in this case, it should make no difference whether the vacuum line is on or off, unless bleed air from the line is being sucked into the throttle body and leaning out the mixture. Try taking the line off and the putting your finger over the hole, your RPMs should go back up again.
 
Keoke said:
Yes, that is a possibility. However, it is now necessary to quote the number on the DIZZY's body to be sure. It should be: 40966 With a letter designation following that number. Check it out and let us know what you find.--Keoke
Click to expand...

I'm going off a picture I took of it when I got it back from Jeff at Advanced, but it's two rows and I'm pretty sure it's "40966 E" on top and then "1088" on bottom.
 
OK Thats good. If Jeff did this DIZZY why not ask him about the Advance unit. The numbers say it has only 3 Deg of advance and it should be 8.---Keoke

P.S. Gonna put me jammies on now and see you in the monin.- /bcforum/images/%%GRAEMLIN_URL%%/laugh.gif
 
I asked Jeff and he said it was okay. He said it was probably replaced at sometime since they only last 15 years or so but that I wouldn't notice a difference between the two units if I wanted to replace it for the proper one. (And I would have to reset my timing again as well.)
 
Well Brandon, I would not be too concerned about resetting the timing it's gonna have to be re timed anyway."I" would have it changed,but it is your call.---Keoke
 
Keoke, where is the number on the vacuum advance unit? The dizzy side has a bunch of raised letters cast on it but I didn't see and numbers (difficult angle to read anything). The other side had nothing on it. You know every time you say anything we all go out and check.
 
tahoe healey said:
Keoke, where is the number on the vacuum advance unit? The dizzy side has a bunch of raised letters cast on it but I didn't see and numbers (difficult angle to read anything). The other side had nothing on it. You know every time you say anything we all go out and check.
Click to expand...


Zip::D TH, on the nose of the vacuum advance unit where it necks down just behind the vacuum pipe connection are three numbers in this exact format; x-y-z. The part number which contains 8 continuous small numbers is inscribed there too. you may have to polish it up to see them---Keoke
 
I talked to Jeff about my vacuum advance and he told me that the #s mean ---- in. of vacuum start advance "5", in. of vacuum full in "12” and the last # total advance "8". I could not see a significant advance effect with or with out the vacuum advance connected during my 4000RPM 35deg advance check. I asked Jeff if my sucking on the vacuum would move the diaphragm. He said it would and after some work I did see it move. The vacuum unit spring link was not connected to the distributor base plate as I was not sure if I could over come the friction in the advance plate. My first test did not yield movement so I investigated the seal between the line and the vacuum unit. The connection was shot and leaking. I trimmed the end of the line and applied a new Teflon ferrule. The leak went away and the connector spring moved with sucking. If you find a similar situation I will be glad to send you a Teflon ferrule as I have a large supply. If you do not want to go through all of this then suck on the line place your tongue on the line and see if it holds.
 
We went out for about an hour drive yesterday evening. I'm noticing the car does not seem to be running as smooth since I adjusted the carbs. Previously, it was running very well, but too rich as it was emitting black particles from the exhaust. It is no longer doing that now that I adjusted the carbs, but it's not running as well.

First, when starting the car it takes a bit more effort. It struggles to hold an idle for quite a while. When it does warm up and idle, it bounces around 550-700rpms. Also, during the drive at a couple different times the car died when I came to a stop. It runs fine throughout the higher rpm range (maybe a tad less smooth) but the low rpm/idle is where I am concerned. I still feel there is room for improvement and I'm pretty sure it's all in the adjustment of the carbs.
 
Where was the choke set while it was warming up and what was the idle speed then. Brandon.??--Keoke
 
Sounds like the problem esperienced with the earlier car vacuum advance units Bob. This was corrected in the later cars, by changing the vacuum advance to line connection ,to a screw on hard line fitting. Glad you got it sorted out.--Keoke
 
/bcforum/images/%%GRAEMLIN_URL%%/savewave.gif Brandon

The choke must be full on when starting. The Idle speed should be ~1500 -to - 2500 RPM . The choke is then adjusted during warm up to show about 1200 RPM. After reaching ~ 165 DEG it should be used to hold the idle at ~ 800 RPM. When the engine is fully warmed ~180 -to -190 Degrees the choke is pushed fully home.---Keoke- /bcforum/images/%%GRAEMLIN_URL%%/hammer.gif
 
Gotcha. But what about the car dying throughout the drive? It would do this when the temp was well above 180' and 30-45 minutes into the drive.
 
Set the "Mixture" screws down one turn each. Record idle speed when hot---Keoke
 
These carbs are becoming a mystery to me now. Just went for a drive and came back...car at 190-200'F. Idled okay at around 500-700, but noticed it earlier at a stop wanting to die. So I screwed down the mixture screws one turn each (turned to the right). I started the car, and it just died. It wouldn't idle at all, even though it just did before I adjusted the screws. Any ideas?
 
Brandon -

What happens when you lift the dashpot piston lifting pins? This is the most important step in understanding if your carbs are adjusted rich or lean.
 
I did that test a few times. Not too much happens. The engine speed may barely increase, but not much at all, and then it goes back to where it was. Sometimes it seems as if the engine speed doesn't change at all when I lift them.
 
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