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sticky floats?

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Hi guys,
I'm not trying to go against the grain here,but has anyone thought that you have a very rich fuel mixture or flooding?In most cases,when a motor has a problem starting after already hot,the spark plugs are too wet to fire.I would make sure that the carbs are not dumping fuel after engine shut down.This condition is easy to see with the air cleaners off.Get the engine hot and in the no start condition and watch the carb bores for vapors.Sometimes the flooding takes a few minutes to dump.Try this and let me know.Got to go to work.
Bobby R
 
If things were too rich, wouldn't normal (warm, not hot) idle run fast? Normal idle has just the right burble. It has taken 30 minutes or more to cool down and restart. Also, in this case, what is your theory on the dying at hot idle in the first place?

healeynut: I do not think I am wasting too much gas; mileage seems normal. the oil splatter on the outside of the left hand float chamber in the picture is old and not recurring. I will clean off the chamber to confirm.
 
Hi Tom,
changing parts and talking about rebuilding carbs is all well and good,but I would do some testing before I do those things.If your coil is breaking down, then checking for a no-spark condition at the coil wire would make sense when the engine won't start.I'm not sitting in the driver seat and can't feel how the engine is cutting out.I offered a simple test.Improper fuel to air ratios can most certainly cut out an engine and they can also stop one from starting.Back in the day of real carburators,this was a very common problem.I hope you find the problem and are back on the road soon.
Bobby R
 
Checking for a no spark condition is the very first thing I would do right after it started acting up on the side of the road. But while safely in your garage, use an ohm meter and clip the leads on the primary side and look for 3 ohms. If your coil is significantly less or greater than 3 ohms, get a new coil on order as that is your problem. Do you see any signs of oily goo leaking out of the coil ?
Ed
 
TomFromStLouis said:
If things were too rich, wouldn't normal (warm, not hot) idle run fast? Normal idle has just the right burble. It has taken 30 minutes or more to cool down and restart. Also, in this case, what is your theory on the dying at hot idle in the first place?

healeynut: I do not think I am wasting too much gas; mileage seems normal. the oil splatter on the outside of the left hand float chamber in the picture is old and not recurring. I will clean off the chamber to confirm.
Click to expand...
I have had a similar hot engine problems that you describe and traced it down to a leaky jet diaphram. The jet diaphram was just bad enough to allow fuel to to bypass it and on a couple of occasions it was enough to go out the overflow tube to the ground and a couple of times it wasn't. The extra fuel(richness) did not make it idle faster as one might expect, but actually caused the engine to die with so much extra fuel.

Key "on", do not start engine, check for fuel overflow.
Patrick
 
I had a similar problem. Stalls at idle when warm. Turns out the choke wasn't coming all way off. More properly, the enrichiner. This is common. People add return springs at the carburettor. Do this: Engine off. At the dash, pull the choke on full. Note the levers that move on the carb. then put the choke off. Push the lever and see if it moves a fraction, even 1/16" If so, there is your problem. A better check, choke on full, choke off. Remove the cover and piston. At the bottom is a collar into which the needle slides. Put your finger on it and push. If it moves, the choke isn't coming all the way off. This is usually caused by a little corrosion and/or weak springs. (Do you have springs?) They might not be sticking every time so repeat the check. Start the car. Push the levers down by hand. See how it drives. Stronger springs and carb cleaner will probably cure it. Otherwise will need to clean where collar slides.
 
Minor update:

I tried to replicate the problem on a cooler day without success. Today though, upper 70s, it died in traffic as the engine temperature climbed over 200. It did not restart so I hopped out to reconnnect the three wires to the new alternate coil I had installed on the theory that the problem was electrical - an overheating coil. First try, it fired right up! Success!

I was very near my mechanic so I stopped in to congratulate him on our bullseye. That was a mistake, because it died again less than 5 miles away. After some time I got within a half mile from home and it died again. Walk home, let it sit an hour, return and start it within ten minutes. But this time it did not even go the 1/2 mile, dying four houses from my driveway. A neighbor who fiddles with an old Datsun came out and dropped the rotor as he removed the cap and it broke into pieces. Maybe it was cracked before? He is suggesting I just buy the regular tune-up parts (rotor, points, condenser, and wires) and replace. His approach is more the one you would expect from a restorer versus a mechanic: "when in doubt, replace the parts".

I realize that I have not even isolated the problem yet since I have only tested one theory and got an uncertain answer. I shall test for flooding since the restart problem (it will sputter occasionally) acts a lot like that. I also need to check some other things mentioned above, like checkng for spark etc. I have confirmed that the fuel pump works fine. Frankly, I have more to look for than my roadside knowledge allows. The coils are very hot to the touch; if they are overheating so easily, why?

I am placing a Moss order in 24 hours since I at least need a new rotor to go any further. What would you include?
 
rotor, points, capacitor, distributor cap. If the wires are old, ignition wires. Stuff is not that expensive and should be done periodically. There were (and still are) some bad rotors out there. Some rotors don't work well with some caps. Could be getting hot and rotor hits cap. Look in your cap for any odd marks. When you buy a cap, some have wires that come out 90 deg from cap and others straight up from the top. The way the wires connect to the cap and coil is different too. A cap with a hairline crack will cause problems. Also, some coil setups came with a resistor for the coil. Resistors act up when heated. When it dies, does it feel like someone disconnected the battery or is there some cough and sputter? On restart, instant or what?

Did you do the carb check I said in my previous post? If that jet is off, it can withstand the richness when the engine is cool but when it gets hot, it is too rich and dies. Have to keep blipping the throttle to keep it going. Dies but starts back up.
 
When it dies, it idles rough briefly and sputters out. Lately the restart, when successful, includes plenty of sputtering.

I have not messed with the floats or jets yet since they only explain the dying, not the restart problem. I am trying those things that seem to explain the entire situation.

My primary frustration is that I lack the fundamental understanding to weigh all the various good-intentioned ideas tossed my way. Heck, one bystander sounds as good as another. I put more weight on members here, but they cannot stand there and get the feedback or say, "here, try this".

I love driving this car way more than I expected, so I will see this through, but the lack of consensus and after today's downward spiral to where the car is now not even functional or in my own driveway, I just need to step away for a while. Keep shooting thoughts, but let's try to focus on ideas that explain both the dying when hot and the not restarting when hot.

Goodnight.
 
Hi Tom,
Let's try this again.The nice thing about this problem, is that it keeps on happening.This will make it easier to find.Checking for a no spark condition isn't really very hard to do.It's just hard to explain.You have to get back to it not starting.Get the beast good and hot and lets stay local(like in your driveway).When it stalls out,turn off the ignition key.At the coil tower,remove the coil wire from the coil.Now place the wire back to the coil tower ,but don't insert it all the way back in.What we are trying to do, is create a thin gap,so you can see the spark jump across.This is a two man job.While someone cracks the engine to start,you keep your eye on the gap and see if the spark is jumping across.If you can see spark going across and the engine is not starting,then we look for another reason it will not start.Don't let this problem get you down.I'm sure you will find the cause.
Bobby R
It's alot easier to see spark on a dark night and don't touch the wire during cranking or running.It'll light up your life!!!!!!!!
 
THe FINAL ANSWER

I think we have the problem licked, and Healeynut gets a gold star.

It appears I had two problems: One: the points were worn. This was solved by installing the electronic ignition I had and have been wanting to install. The bad points, combined with Problem Two, explain the failure to restart.

Problem Two was/is a worn throttle shaft or bushings on the forward carb. It wriggles some and our theory is that air is leaking into the carb, especially when hot parts have expanded a bit, causing the engine to sputter and die at idle. The temporary solution was to adjust idle up to 750 rpm or so; it still sputters a bit when hot and wants to die but just manages to stay alive. I now know how to adjust the idle and can crank it up a bit more if the stall recurs before I have the carbs rebuilt. Apparently the "rebuild" 11,000 miles ago by the former owner did not deal with the shaft; surely they would last longer than 11,000 miles?

Dave and others who suggested leaks in the lines get a silver star. Everyone who has put up with my frustration and ignorance gets a platinum star. I have a local guy who can help me, and this seems to be the best way to solve complex diagnostic problems and educate the ignorant. Even he was relatively clueless until he stood beside as it died. The slow sputtering and final silence sounded like fuel starvation to him (me too, which is why I originally asked about the carbs), and he went right to it.

For the kind of question this forum is guaranteed to nail, see my sequel on tachs.

Thanks for all the suggestions! Even when you miss the bullseye, I learn, and for that I am grateful. Because this car stays here.
 
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