Truck dies while in gear and stopped, but not in neutral or motion.

[cheetah79857985]

I have an automatic '77 610 Datsun and the engine will die on me while I am in gear and not moving (stoplights, stop signs, parking, etc...). It has zero problem or indication of this while actually in motion and in gear or while stopped and in neutral. I have increased the idle and checked all my hoses, but am lost beyond that. Does anyone have any ideas?

[racerx]

check to see if you have any vacuum leaks. While truck is idling, spray carb cleaner around carb, its base and hoses. If rpm goes up then you have vacuum leak. Also check your choke setting and float.

[cheetah79857985]

Well, while attemtping to DO your suggestion, another problem cropped up. Brand new one.

 

The engine will turn over, catch, be on for a brief moment and then die (this is normal, not the problem). The problem is that now, after the initial start-up, the engine won't turn over! And it sounds as if the battery is dead, but everything needing power (lights, radio, etc...) turns on. I guess I'm just looking for confirmation if my guess is wrong or not; the battery is no good anymore?

[datzenmike]

If you have headlights and they seem normally bright then the battery has power, it's just not available to the starter. If it cranks slowly, possibly the positive cable (the big one) is not making good contact at the starter terminal, the starter is loose and not making good ground contact with the block, or the negative ground cable from the battery is loose or dirty where it is bolted to the head.

 

Inspect both cables and the end lugs that are crimped on for damage, wear or corrosion. I assume the battery terminals are clean and the cable ends are in good shape and are properly tight.

 

If it does not crank over at all or the starter chatters, the start signal to the starter solenoid from the ignition switch may bad. Look on the starter, there should be a large cable from the battery and a small single wire (possibly Black/Yellow stripe) The Black/Yellow wire should have 12 volts when in the start position. If not suspect the ignition switch.

Edited November 7, 2008 by datzenmike

[datsunaholic]

Well, this second issue could be something else. When it doesn't start, do the lights dim out and the gauges fade when turning the key, or do they stay at full (or close to full) intensity? If they fade dramatically it's the battery. If they don't, something in the starter circuit went haywire.

[cheetah79857985]

Yeah, I gave the battery and it's wires a cursory inspection. Everything is tight and clean. The gauges and lights did fade out significantly though. When I first turn the key, the engine cranks, or tries to crank, then as I keep the key in the start position, it just stops trying to crank and I am left with the chattering-like noise. Guess I'll take the battery to the auto-shop and have it tested. Thanks guys.

[Nicholas7620]

try reading this to help you get started.

 

http://www.recarbco.com/technical/newtrouble.html

[DISLEXICDIME]

your first issue sounds like points . do you have a electronic distributor or points

[cheetah79857985]

Thanks for that link, that will help a lot, regardless. I guess I'll check the points :( I did a full re-wiring under the hood just a year ago because the points went bad and I didn't figure it out until I had... re-wired! haha The distribrutor is on nice and tight though, and I'm pretty sure it's electric. I don't really know what a non-electric one looks like though.

[DISLEXICDIME]

if you have an electric dizzy you will not have points you will have a reluctor wheel inside . if you have points and the gap is wrong the car will die when it is idoling . so if you have points under the cap then you do not have a el dizzy

 

hope this helps

[cheetah79857985]

Well, the second issue ended up being a bad battery, so easy fix there. My points and gaps are fine, but I did notice the choke regulator had fallen off the flap's pin (I don't know if these are the correct terms, but that's what it looks like). So I'll see if the problem is better or gone.

[cheetah79857985]

I don't have any vacuum leaks, but I set my choke to stay open all the time and I haven't had it die since. It will "jump" once in awhile though. I probably should have mentioned this earlier, but I don't have the original carb, I am using a weber.

 

The metal coil that is supposed to move the pin/arm that operates the choke; is it supposed to tighten, or loosen as the truck warms up? I let the truck idle for about five minutes and I didn't notice any movement, so I wonder if it's working at all, and how can I check that for certain? Do I need to buy a voltometer (tool that has two metal tips and tells you how many volts are going through something, among other things. I just don't know the tools real name) and check the wire that runs into it?

[cheetah79857985]

I used a voltometer but I got two different readings. .08 for one reading and 16ish for another :S What is is supposed to be?

[datzenmike]

The choke coil should unwind as it heats up.

 

The heater for the coil will show some resistance is it's goo, and infinite resistance if bad. Test using a multi meter set on the resistance scale. One lead on the input wire (ignition off) and ground the other lead to the side of the carb

 

The input wire to the choke heater should read 12 volts more or less compared to the ground on the carburetor, with ignition on and running.

[cheetah79857985]

I checked the resistance and it turned out good. I re-adjusted the choke position. I turned on the truck and let it idle and the butterfly opened up just fine. But now it has been sitting for 24 hours and they have not closed. They've closed partially (less than halfway), but shouldn't they close to within just a fraction of completely closed? It still does the jumping while in gear and stopped. It's lessened, but still there.

[cheetah79857985]

So after several days, the butterfly didn't close. First of all, can you guys tell me what the name of this piece is? It's the piece that is supposed to operate the arm the opens and closes the butterfly. Secondly, does it look like it should? Should it be tightly coiled or what? Third, do you have any suggestions or advice on why the butterfly may not close to the position I had started it in? Thanks guys.

 

[datzenmike]

That's the bi-metallic coil. Behind it is the electric element that heats it up. As it heats it expands and un winds in a counter clockwise direction as it sits in that picture. For the choke butterfly to close, the loop at the bottom must engage the 'tang' or lever on the choke assy when it is installed. Because of design, the cooled spring exerts a closing pressure on the choke butterfly but the throttle is in the way preventing this. When starting the engine you must depress the throttle allowing the butterfly to close and set the fast idle cam in position. When the throttle is let go the fast idle screw sets on one of a series of steps on the fast idle cam.

Edited November 23, 2008 by datzenmike

[cheetah79857985]

So, it sounds like you are saying if I had just started the truck, the butterfly would have popped into the correct position, and that that is the way it is designed to function. Ha! Ok, thanks, I will go put it back together and drive the thing.

[datzenmike]

Yup, pump the gas once (or twice) to richen it up and set the choke butterfly, and crank it over.

[cheetah79857985]

:( So after checking for vacuum leaks and finding none, cleaning the air filter, replacing the fuel filter and spark plugs, and re-positioning the choke to operate properly, it still has the same problem.

 

It will die while I am stopped and in gear, but operates perfectly while driving (though I should specify at high speeds). While stopped and in gear the engine will "jump" forward once, twice, maybe a few times, and then it will die. So to counter this I throw it in neutral (automatic BTW) and wait until it's time to go. When I go into gear it will move forward but very badly. Pressing the pedal too much causes a reaction that makes me think it is getting too much fuel, like it's flooding. In addition to that, it accelerates very slowly until I hit about 30 MPH, which is pretty close to 3rd gear (four speed). If you consider the type of gap-in-traffic you normally wait for befor you make a left turn, I usually wait for one that is two to three times that size so I have enough time to make the turn. I also suspect that starting on an incline makes this worse, but the incline I am talking about can't be more than ten degrees (Basically, the incline you get from the middle of the road to the end of it so rain runs off to the sides.) And it will die sometimes when I go from neutral to gear, hence why I wait for large gaps in traffic when turning left, although I am pretty sure that this particular reason is because the engine is still cold as it happens, most of the time, at the beginning of my day.

 

Any advice is appreciated! Please and thank you!

[Cuts metal like mad]

I reread through this thread and did not see where you are located, but... Obvious question is, why haven't you installed a weber yet?

 

Also being an auto, have you checked your trans fluid yet? I think it's about time d to do so.

[cheetah79857985]

I do have a weber (post 12) and I did include checking the transmission fluid while trying to fix this problem.

 

I am wondering, would a higher idle help get rid of this problem? I already have it set higher than what it was when I bought it, though I couldn't tell you the RPM because the truck doesn't have a tachometer.

[Cuts metal like mad]

have you tried warming it up completely before driving?

 

I don't know... I'm reaching at this point. Timing?

 

Since you have a weber I'd try richening the Idle air mixture... 1/2 turn at a time...

Edited December 5, 2008 by zuum510

[datzenmike]

I do have a weber (post 12) and I did include checking the transmission fluid while trying to fix this problem.

 

I am wondering, would a higher idle help get rid of this problem? I already have it set higher than what it was when I bought it, though I couldn't tell you the RPM because the truck doesn't have a tachometer.

 

Don't go high idle, find the problem. Not good to shift into gear with high idle... rough on tranny.

 

 

Webers are sensitive to too much fuel pressure and will flood. Check your plugh.... if black and sooty, it's too righ or flooding. I think it sounds like not enough fuel... running lean. Check plugs. Very light color is lean. White is super lean.

 

Check timing advance.

 

Check valve lash. A tight valve won't close and cause a power loss if exhaust and a vacuum loss if intake.

[cheetah79857985]

Now you're getting a little beyond my knowledge. I can check the spark plugs no problem, but how do I check the timing advance and what/where is the valve lash?