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Help timing my truck

charm said:
I don't know what brand it is. It's a pretty basic, non-adjustable timing light with the pick on the number 1 plug as close to the plug as I can get without having it melt to the exhaust manifold. Also, it's powered by the car's battery.
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Sorry. I was asking "7Mopar" to clarify his "test-light" connection points and test-light configuration (one lead, 2 leads) when using a test light to set static timing.

- EM
 
Any 12 volt light will work. I clip to - side of the coil and stick the probe to gound. At the spark plug just a simple inline spark tester. Same think can be done with the old points setup. Clip to distributor side of coil and probe to ground. I just stick the probe anywhere the light will light while the clip is on a hot wire. If you have a light with clip on the postive and negative it will also work. I have always just made do with what was available.
 
charm said:
I don't know what brand it is. It's a pretty basic, non-adjustable timing light with the pick on the number 1 plug as close to the plug as I can get without having it melt to the exhaust manifold. Also, it's powered by the car's battery.
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This method also works if you have a timing light. Engine doesnt need to be running. Just the ignition on.
 
Would you go over the test light procedure as if I were an idiot (since I feel like one at the moment)? Or a YouTube video would work as well.

I did spend a little time on the truck today. I removed the exhaust to check out the suggestion from my local NAPA guy, no clog, no change, and it's louder (obviously) now.

I did a once over, or would it be a fifth or sixth over?, looking for vacuum leaks. Found a cracked plug, changed that. I tried plugging all of the vacuum ports and that helped a little. I rehooked them up, one at a time and it seems like the only one that really messed with anything was the vacuum advance.

So, the truck, newly louder, doesn't totally stall when you hit the gas, but it still stumbles a touch with a hint of a backfire. With all of the poor running, I may try a new set of plugs even though the set in there only has a hundred or so miles on them (if that). They do have a lot of time under poor running conditions, so maybe clean plugs will help? Last time I looked at them, they looked pretty good.

When I first got the truck it had a pretty messed up fuel system. The tank has been restored, but, other than making sure the metal fuel lines were clear, they weren't cleaned. There isn't that much fuel line coming from the in cab tank to the engine bay, but it might not hurt to try swapping the fuel filter. Shouldn't be enough to clog it, but who knows?

So, spark appears good, but I'll test, just 'cause. Fuel is probably good, but I'll swap the filter, just 'cause. I still can't find a timing mark with the timing light even though I ensured I was at TDC before the distributor have checked twice since. I can still line the timing mark up with 0* and have the #1 intake and exhaust closed with piston at top of its travel.

It is certainly plausible I got a bad distributor. Would bad electronics in the distributor allow the engine to idle well, not take much if any load, and not show the timing mark with a timing light?

So far I seem to be working towards figuring out all the ways not to fix truck. At some point I'll find the one way that actually works.

Thanks for all your help and patience with me!
 
If it stumbles on acceleration It could be a bad accelerator plunger in your carb. If you look down the top of the carb with the engine shut off and push the accelerator yo should see shots of fuel. If not your plunger needs replaced
 
MILO said:
If it stumbles on acceleration It could be a bad accelerator plunger in your carb. If you look down the top of the carb with the engine shut off and push the accelerator yo should see shots of fuel. If not your plunger needs replaced
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Carb was just professionally rebuilt. Spray looks good. Originally thought the issue was vapor lock, if that helps.
 
7mopar said:
Does the fuel system have a vapor separator with a return line?
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No. This was on my list until I noticed that it was exhibiting these symptoms not just when the truck was cold, but when it was in the low 60s, upper 50s, first thing in the morning. It was doing vapor lock things, like running nice when cold then having issues after driving for a long while (usually while going up a hill on a two lane highway with 55 mph speed limit...made me real popular). Now, it's doing those things right after start up even when the air temp and engine are still cold.

That said, I do plan add all that to ensure I don't have vapor lock issues in the future. For now, it would be good if I could find the timing mark on my smooth idling truck. The same timing mark that I used to set the timing to 6* advance on the old, bent internalled distributor prior to replacement of said distributor.
 
Yea I could not find a good y-tube either. At present I only have internet access and no why to even post pictures alone video.
 
Update time!

Spent some time under the truck today. I have decided to move forward with the assumption that the timing mark issue and the driveability issue are separate. As such, I decided to try timing the engine with a vacuum gauge. This, I thought, went well. I discovered the engine ran better, with more vacuum at idle, with the port where I had the PCV valve plug in, plugged. I moved the PCV to share a vacuum port in the manifold itself. With the vacuum advance port plugged, I was able to get about 18 in Hg. With the vacuum advance attached, I managed about 20 in Hg...steady. The idle seems a little high, but I can adjust that down later.

With good vacuum and smooth idle I was excited to test drive the truck. Made it an entire city block before I hit the gas and it fell on its face. Still, any load on that engine and it isn't happy.

Talking to somebody at NAPA, he suggested going back to basics, plugs, wires, spark, gas, etc. Clearly it's getting some spark and some fuel. It makes noise, vacuum, and idles. Heck, it is sorta driveable. But clearly the quality of the fuel delivery or the quality of the spark is impaired. I tried putting the cap from the old distributor on, that did help a bit. I found, finally, the old rotor and will try that later as well. (By old I mean I replaced them when I bought the truck and they've got a few hours of testing on them and maybe 100 miles).

I'm also thinking I should test the spark plug wires. I'll check their resistance and make sure they're all up to snuff. I have checked the spark plug and that was fine.

Engine compression? Would a bad cylinder do this?
 
Just a thought. While tweaking the timing, engine running, I was feeling some current. I recall this being common, but is it a sign of a bad plug wire?
 
Where exactly was your hand while feeling current? Top of cap or side. Side of cap would not be normal. Even top of cap would not be acceptable with new wires.
 
charm said:
Update time!

Spent some time under the truck today. I have decided to move forward with the assumption that the timing mark issue and the driveability issue are separate. As such, I decided to try timing the engine with a vacuum gauge. This, I thought, went well. I discovered the engine ran better, with more vacuum at idle, with the port where I had the PCV valve plug in, plugged. I moved the PCV to share a vacuum port in the manifold itself. With the vacuum advance port plugged, I was able to get about 18 in Hg. With the vacuum advance attached, I managed about 20 in Hg...steady. The idle seems a little high, but I can adjust that down later.

With good vacuum and smooth idle I was excited to test drive the truck. Made it an entire city block before I hit the gas and it fell on its face. Still, any load on that engine and it isn't happy.

Talking to somebody at NAPA, he suggested going back to basics, plugs, wires, spark, gas, etc. Clearly it's getting some spark and some fuel. It makes noise, vacuum, and idles. Heck, it is sorta driveable. But clearly the quality of the fuel delivery or the quality of the spark is impaired. I tried putting the cap from the old distributor on, that did help a bit. I found, finally, the old rotor and will try that later as well. (By old I mean I replaced them when I bought the truck and they've got a few hours of testing on them and maybe 100 miles).

I'm also thinking I should test the spark plug wires. I'll check their resistance and make sure they're all up to snuff. I have checked the spark plug and that was fine.

Engine compression? Would a bad cylinder do this?
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Remember the engine is basically a compressor that creates power. You are getting some descent vacuum readings. I like to hook the gauge to the manifold port and leave everything else ported as normal. Have you by chance checked the manifold for carbon build-up?
 
7mopar said:
Remember the engine is basically a compressor that creates power. You are getting some descent vacuum readings. I like to hook the gauge to the manifold port and leave everything else ported as normal. Have you by chance checked the manifold for carbon build-up?
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When I had the carb off, resealing it, the inside of the manifold looked fine. Other than that, I have the EGR port blocked off with a plate.

As far as where I was shocked, pretty sure it would be considered the top of the cap. I was grabbing the top of the cap instead using the vacuum advance can to adjust the timing. So maybe I'll try replacing the plug wires, again.
 
Where you been getting plug wires that the insulation is that bad? If you are getting shocked they are more than likely cross firing with more voltage going threw them under load.
 
My last ones came from NAPA. Bought a set of lifetimes. I don't think they cost $30 and have been there 6 years now. Happen to think about it the spark plugs have been there that long to.
 
7mopar said:
My last ones came from NAPA. Bought a set of lifetimes. I don't think they cost $30 and have been there 6 years now. Happen to think about it the spark plugs have been there that long to.
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Whelp, wasn't the plug wires.

Could it be that I'm just an idiot trying to run a Quadrajet on Dodge 360? Would the wrong carb cause all this stumbling?

The choke is most certainly opening. I was worried it wasn't opening on the secondaries so I rigged it open. That wasn't it.

Could it be that the Quadrajet demand more fuel than the factory fuel pump supplies? That would certainly allow for the nice idle and the stumbling under load?

I would rather not figure out how to wire and plumb an electronic fuel pump and return line, but if it makes the truck run right, I'll do it!
 
The Quadrajet was original equipment on the Ram 360 in 83. Maybe time to actually check the fuel pressure. If you can run the gauge to some where it can be seen while going down the road. Just don't put it in the passenger compartment.
 
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Yeah, my 87 W250 came with a quadraje on the 360 but that burnt up and was long gone by the time I got it with a nasty holley and burnt off paint on the hood. I now have an edelbrock on it and life is much better.
 
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