Stubborn starting question...

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Your problem might be as simple as the choke pull off is shot, not opening the choke when the engine starts. Then it floods the engine.
 
Your problem might be as simple as the choke pull off is shot, not opening the choke when the engine starts. Then it floods the engine.

I think you're onto something.

I played with the mix and dropped it to 1/2 turn and it worked much better; without the staining of the pavement and rich flooding. I then dropped the idle down and she ran smooth.

I am wondering how much the up and down weather might be playing with things too. If the choke is sticking, like your suggesting, and I will check, and if the weather is spotting at 20 F one day and 70F the next, maybe I'll be adjusting the carb for cold/warm weather daily, till a stable temp results on the coast?
 
Your problem might be as simple as the choke pull off is shot, not opening the choke when the engine starts. Then it floods the engine.

You need to start the car cold with the air cleaner off. Press the gas pedal to the floor ONE time, then check to see if the choke really is almost fully closed, just a tiny bit of clearance. There is a specification, but I can't find it now.
I'd bet it's in here:

[ame]http://u225.torque.net/cars/SL6/docs/Carter_BBS_Service_Manual.pdf[/ame]

If the choke plate is right, start the engine and watch what happens on the carb. When the engine starts, manifold vacuum starts to pull the choke plate open if the choke pulloff is functioning. If that doesn't happen, the choke plate will remain mostly closed, the engine will run rich and you'll soon have a black sooty patch on your driveway. Hope that helps.

BC
 
The above is good, because it checks the linkage, but you can also check the choke pull off after the engine is running. All the time the engine runs, the pull off should be "sucked" in. You can unhook the vacuum line to the pulloff, hook it back up, and watch it "suck in" if it's working.

Also look for sticking linkage parts, bent, stuck, corroded, gummed up, etc.
 
Ditto on the "choke pull-off" or "unloader". I am guessing you don't know what that part is since "choke sticking" isn't the same. Look for photos. It is bolted near the top of the carb, with a short linkage to the choke plate and a vacuum tube from the bottom of the carb to it.

They often go bad (carb cleaner ruins the rubber diaphragm). Besides the steps above, a good way to test one is with a hand vacuum pump. Without that, the "poor man" method is to disconnect the vacuum hose, push in the plunger, block the tube with your finger, and see if the plunger stays in. If it moves out, the diaphragm is bad. Costs <$10 and makes a big difference in easy starts and avoiding "dying rich" on cold mornings.
 
You need to start the car cold with the air cleaner off. Press the gas pedal to the floor ONE time, then check to see if the choke really is almost fully closed, just a tiny bit of clearance. There is a specification, but I can't find it now.
I'd bet it's in here:

http://u225.torque.net/cars/SL6/docs/Carter_BBS_Service_Manual.pdf

If the choke plate is right, start the engine and watch what happens on the carb. When the engine starts, manifold vacuum starts to pull the choke plate open if the choke pulloff is functioning. If that doesn't happen, the choke plate will remain mostly closed, the engine will run rich and you'll soon have a black sooty patch on your driveway. Hope that helps.

BC



This was real helpful. Thanks.

I adjusted the carb and idle and she's running pretty well, but I want to be prepared for a carb rebuild. Its a B&B carb but they made 4 versions and the tab is gone off this one.

Any idea how to determine which? 3 of the versions produced use the same rebuild kit and the fourth one a different set.

As soon as i can find an affordable OEM shop manual, I'm reading it cover to cover! This is the first car I've ever owned where I hadn't gotten one right away.

I just don't like reprints!


Slainte,
 
Ditto on the "choke pull-off" or "unloader". I am guessing you don't know what that part is since "choke sticking" isn't the same. Look for photos. It is bolted near the top of the carb, with a short linkage to the choke plate and a vacuum tube from the bottom of the carb to it.

They often go bad (carb cleaner ruins the rubber diaphragm). Besides the steps above, a good way to test one is with a hand vacuum pump. Without that, the "poor man" method is to disconnect the vacuum hose, push in the plunger, block the tube with your finger, and see if the plunger stays in. If it moves out, the diaphragm is bad. Costs <$10 and makes a big difference in easy starts and avoiding "dying rich" on cold mornings.

Again, thanks! Good tip.
 
You have to read down through the thread, I don't remember what all is there. Also go over to the link for MyMopar. At there very least, there's a 67 Dart over there
 
Bear with me. I'm new to this list, but not new to driveability.

Nobody has mentioned the possibility that his timing chain may have skipped a tooth, am I right?

To run well, you need fuel, a good and properly timed spark, and good compression. If you didn't have to move the distributor very far to re-establish good initial timing, your timing chain is probably ok. But if you had to move it quite a bit... check your compression. If it's low, odds are your timing chain has skipped. After all, your car ran well, and then was a "little" rough at idle (where the chain slops around) and did NOT start after shutoff, in the convenience store parking lot -- a classic symptom of timing chain problems. If this is the case, you can install all the electronic ignitions and new carbs you want without fixing the problem.

Another good way to investigate a loose chain is to put a socket on the crank (I'm assuming you CAN on the 273, I don't know, but if you can't, then use a strap wrench or whatever turning device you can "McGyver") and then take the cap off of the distributor. Work the crank one way and then the other. If you get 10 degrees or more of movement on the crank before the distributor rotor moves then, Houston, you've got a problem.

1. Good spark, properly timed.
2. Fuel.
3. Compression.

These are what you need.

Hope this helps.

Ex-tuneup mechanic,
JD
 
oops, did my last post get into the wrong thread? I looked upward to check to see if anyone HAD mentioned timing chain, and all of the feedback looked unfamiliar... do they truncate it or did I screw up and post to the wrong place?

With possible egg-on-face,
JD
 
Ok... me again. Yes, I see I'm still in the right place.

One other even quicker check of timing chain -- does your timing mark bounce around a lot at idle? That could be a tip-off of slop there.

I'll quit now.

Sleepy, I am,
JD
 
Ok... me again. Yes, I see I'm still in the right place.

One other even quicker check of timing chain -- does your timing mark bounce around a lot at idle? That could be a tip-off of slop there.

I'll quit now.

Sleepy, I am,
JD



You guys are really helpful, all of you. Thanks.

I am beginning to suspect a combination of gremlins. Last night, after running smooth as a Taco Bell inspired BM, she started coughing out on me while idling. In fairness, I didn't let her warm up.

I stopped at a store and when I came out she wouldn't start. The starting motor was turning but no spark. I checked the fuel filter [I replaced the old one with a new clear one that let's me track the fuel flow since I last emailed you] and she was full. I tried some carb start and she didn't even try to catch.

:banghead:

This morning I went back to the parking lot where I had left her with my doctor's bag of tools and a fresh battery. Before doing anything else, I hand primed the carb to see if anything was getting into the bowl and noted adequate spray. So, planning to check the line from the pump to the carb, in case the flow appeared restricted, I tried the ignition to clear the bowl.

She started.

She not only started but she ran and idled fine, if not fast.

I'd brought a timing light with me and noted that she's slipped out of timing a bit about two points off dead since I set her two weeks ago. I also ran my engine analyzer and noted she was idling at 1600 RPM.

To avoid a tow charge, I held off playing with anything else and took her home. :burnout: She ran fast, wanting to pull at every stop and when I got home she was still advanced. Two times she hesitated quite noticeably.

Now, here's what i am wondering; might I have a distributor problem, advancing the timing, and also maybe have a fuel pump going out or the choke plenum issue mentioned? It might also be the timing chain suggestion, but I am wondering if I am setting my timing on an inconsistent fuel pump or worn choke which is causing me to chase my tail; not a very dignified activity?

I seek a delphinian solution to a gremlin infestation!

What do you think, oh oracles of the mopar? :prayer:
 
Ok quit flopping around like a fish out of water, LOL

You say you "checked the spark" and there was NONE

STOP RIGHT THERE

Just exactly what did you do to accomplish this? Details of how you did so?

Now if there REALLY was no spark, that should have been a giant clue.

The very first thing I would have done is get out a clip lead, hook from the coil + terminal to a battery source, and re-crank and re-check for spark, and go from there.

You cannot just wonder. You cannot just guess. You actually have to CHECK some of this stuff. Now I realize that if this is a sometime thing, otherwise known as "an intermittent" this can be difficult.
 
Early timing gears have/had plastic caps/covers on cam gear teeth some of these may be coming off and affecting timing drift.

Do you know any history on this motor?
 
Ok quit flopping around like a fish out of water, LOL

You say you "checked the spark" and there was NONE

STOP RIGHT THERE

Just exactly what did you do to accomplish this? Details of how you did so?

Now if there REALLY was no spark, that should have been a giant clue.

The very first thing I would have done is get out a clip lead, hook from the coil + terminal to a battery source, and re-crank and re-check for spark, and go from there.

You cannot just wonder. You cannot just guess. You actually have to CHECK some of this stuff. Now I realize that if this is a sometime thing, otherwise known as "an intermittent" this can be difficult.



I may not be using the same vocabulary as you. My experience is limited to shade tree experimentation.

When I said "checking for spark" I was referring listening for any ignition past the turnover of the starting motor [the car was on the side of the road at the time.

When I got it home I checked more specifically by pulling the middle distributor wire free and seeing if it arced against the breather case, and putting an old plug in the number 1 wire to see if there was any pop. That was only after I got her safely off the street.

I am leaning toward some earlier suggestions regarding a combined choke-fule pump problem, confounded with a slipping distributor. She shouldn't have gotten that far out of Time that quickly.
 
Early timing gears have/had plastic caps/covers on cam gear teeth some of these may be coming off and affecting timing drift.

Do you know any history on this motor?



Sadly, no.

This was an impulse buy. I did get her checked at the local AAA before buying it, but the previous owner knew nothing about cars except where to put gas and he had a mechanic that made some repairs [that I learned later, after buying it] that might have caused some problems [ie. drilling holes in the brake shoes to force springs to fit; she has new shoes now, minus any extra holes, / or / by passing the wiring to the fuse box with a series on inline fuses, too small for the loads, also repaired.].

I've done a lot of rewiring and repair of the inner door linkage, locks, and recently the tune up efforts previously discussed.

A little bit at a time!

Thanks for the tip about the plastic teeth.

Regards,
 
Finally got my shop manual today!

Will be nice to have a set of instructions!

I'm going to run her through some tests this week, hopefully now with some standards to compare. She runs smooth as silk some days and then randomly chokes on others, like this week.

Thanks all for your input and suggestions. I'll keep you informed.
 
When I got it home I checked more specifically by pulling the middle distributor wire free and seeing if it arced against the breather case,.

OK, but keep this in mind. Just about all "no run" problems are in these categories:

spark, fuel, compression.
 
I hear you.

I have replaced the coil, spark plugs, wires, points, condenser and checked the battery for spark. Not much left to replace or repair!

Before making those modifications I'll get the carb rebuilt.

I'll let you know when its back this week.

Again, thanks,,,
 
The camshaft timing skipping a tooth is a good suggestion. However, most here would say that would cause a permanent problem, not the erratic "no start" condition experienced. You can easily test for slop in the chain by turning the crankshaft by hand forward, then reversed and see how much "lost motion" in the distributor rotor. Many posts here detail that. If <5 deg slop, unlikely it could have skipped, but who knows if your engine has the nylon cam sprocket since might have lost some teeth.

I am confused by the 1600 rpm idle and the timing light measurements. Your engine would be "racing" and would kick hard when put in drive. I wonder if the idle (600 rpm) timing is way too retarded (after TDC). Forget the manual specs. Most people find their car runs better with much more initial timing, say 15 deg BTDC at least. Some racers even go further, since they don't care much about idle anyway.

If it only runs well at high rpm, you likely have a vacuum leak, but could be a bad distributor (check "centrifugal advance" works), or a timing chain that skipped a tooth (runs better at higher rpm, drag racers do that on purpose).
 
Give that man a cigar!

Well, I have news and got back to a wyfy bar to read this today, only to find out that the previous poster had it right, at least partially.

Yesterday I went by to get the carb adjusted and she died again. I checked the points; all burnt.

I had a spare set of point and condenser I bought a week ago in the glove compartment, so I put them in. They burnt out in the test drive around the corner.

A old time mechanic at the shop heard about my woes and gave me some advice, that I am sharing with you.

He said that buying points for these cars from Autozone or Advanced was a waste. He'd had similar problems, and it was only after buying a set of heavier [Blue Streak] breaker points that he could get his late 60's Ford Mustang to work dependably, as the material used in the cheaper sets that he got from local chain stores kept burning out.

Well, in the mean time, I had bought a replacement distributor with a lifetime warrantee from O'Reilly, [the only place that had one available in town, and it initially worked but it burned the points out again in the parking lot. So I ran down the street and got the Blue Streak points that he suggested and they worked. She's starting well and I got the carb adjusted and Rubie's running smooth [for now!!!}.

Now, I am not saying that this was all absolute, but I swapped three sets of points and condensers in an afternoon, 2 from Autozone, one from O'Reilly's that came in the distributor, that same day and only the heavier set worked, getting me home.

So the previous poster was correct that the cam was slipping [there was heavy wear on the distributor shaft, making opening the points up difficult, and the new distributor seems to work better with the Blue Streak points, but if what I learned is true, then buying a set of points over the counter will lead to early burn out?

I have to field test this, but has anyone else heard this about points? Honestly, I had not heard that points were that cheaply made, but there did seem to be a visible difference in quality when I compare the old sets with the Blue Streak.

I'll field test her over the next weeks and if she holds, I'll be following advice posted here and getting an electronic distributor. I swapped out points when necessary, in years past, but chasing points this much was no fun. If its a matter of not trusting what I am buying over the counter, I'll want an alternative.

What do you think? Am I on to something?
 
So the previous poster was correct that the cam was slipping [there was heavy wear on the distributor shaft,

What do you think? Am I on to something?
At the risk of speaking out of turn, I am pretty sure the cam post was talking about the "timing chain" slipping a tooth on the "camshaft gear", nothing to do with the distributor internals. A skipped tooth can happen if the gear is greatly worn, or an old and brittle original nylon gear (used on some early cars).

I think you will forever be spending much time fooling with points. I sure wouldn't have bought a new points distributor. Better to have bought a later (~1972+) electronic distributor. Add a cheap GM HEI module and coil, lose the ballast, and your ignition would be much better and more reliable.
 
I would guess points burning up is some other problem OTHER than bad points, here are some check points, LOL pun fully intended

BATTERY CHARGING VOLTAGE. Running, battery voltage should be 13.8--14.2 with engine warm, in no case above 14.5

COIL could be bad. Check coil running voltage. This varies greatly, might be, idling, anywhere from 10-12 volts but in no case more than 12. Typically less.

SUSPECT bad condenser. Check that the external condenser is hooked to the POSITIVE coil connection, and that the distributor wire is hooked to the NEGATIVE coil connection. The external condenser is for radio suppression

SUSPECT points gap. If the points are set too close, they will burn. Check with a dwell meter. ALWAYS set points "on the wide" side as they will wear closed. Always set timing towards "more" advanced because as the points wear "shut" timing will retard. Always put a tiny tiny amount of hi temp lube on the points rubbing block on the "approach" side. Points, back in the day when "points" were "real" came with a tiny capsule of lube.

MAKE SURE your feeler gauge is clean, and again, set with a dwell meter. Hell, I never even used to USE a feeler. I used to estimate gap, set them with a dwell meter (scope) "on the starter. Then I'd start it up and recheck. They would change some between "on the starter" and running, but after you did this a few times, you knew how much to "adjust." Back in 70--74, I set hundreds and hundreds of 'em
 
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