Slant 6- Idle and Running

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F that stuff, unplug and cap all the vacuum lines 'cept distributor advance and see if she idles hot. Lots of temperature switched vacuum ports on that cobbled smog attempt. Makes sense that some dead open vacuum leak would cause the motor to lean out and die when warm...my "hot vacuum leak' theory.
 
IIRC that CA delay solenoid prevents the distributor from snapping back to full idle advance (and causing unburned fuel) when you get off the throttle, sort of bleeds it off over about 3-4 seconds. My Mazda had same sort of delay solenoid on it like that. the open port is in fact left open to vent to atmosphere. Mine was acting weird: it would mechanically hold the throttle open too for 2-3 seconds via the pot it controlled after you let up on it. very strange experience in a manual trans in traffic when you are feathering throttle to keep up with slow traffic. You get off gas and it keeps pulling for 2-3 seconds! Found it would not hold a vacuum so I plugged the inlet with solder (metal pot) and left the hoses on so it would pass visual here in Commifornia. made it air tight and no more delayed throttle.
 
If yours has the CA emissions package there is a chance it will have bolt under the carb with a hole in it (sorry can't remember the correct name). If you take the carb off unscrew that bolt and plug it with another bolt. I won't cause this problem but does not help it run any smoother.
 
I think your referring to the EGR holes in the V8 manifold floor? Slants used a EGR valve at edge of intake under carb. HIs post #21 didnt show an EGR at that location. May want to check that threaded hole in intake under carb...EGR shown and blue bolt boss above it is where you got nothing.....
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UPDATE, my journey continues...

If you read this and something stands out, please yell at me to check something. This car is kicking my *** ha but its fun. I get short windows to work based on looking after a 3 year old. I only get a few minutes to diagnose things when running since it wont run when warm yet.

The commiefornia emissions, doesn't make much of a difference connected or not, so its not connected. I also have the pump not seen in most photos of A-body slant 6's I've seen. I'm guessing these are all unrelated to my problems.

Valves. Valve lash were off but it doesn't seem to change any of my problems. Set to 0.011 and 21 based on my moderately warmed engine.

Timing. I can't set the timing as I don't have timing marks, so I can't report what my timing is set to. I know its meant to be a welded on bracket, but mine doesnt have it. I can say retarding or advancing the timing by ear does nothing for my problem, it wont run or start warm. I have spark on all cylinders. Haven't compression tested yet. When I look at my timing under the light, my timing notch wanders. It is not stationary. (???) I have capped the vacuum advance and checked for vacuum leaks. Why would my timing be wandering? Maybe this is the source of my problems afterall. Not sure what to check here other than to replace ignition components. Obviously I can't check the timing warm, btw the engine is idling pretty calm during this warm up phase. Coil has been replaced for giggles.

Fuel leak. Now I have a fuel leak from my fuel pump, not from the fittings but from where it enters the block. So that'll need to be replaced. I didn't have a leak here before but perhaps this could have been contributing.

Hot vacuum leak. So far all I've done to test this is do the carb cleaner vacuum test, at various temps, but surely the vehicle would start back up when warm? it will crank when warm but not start or even fire. If I choke the engine, then it will.

Carb rebuild incoming, hoping this is the holy grail.
 
I would check the timing chain for excess stretch and distributor shaft for slop. You need to have some kind of timing marks, somehow someway to have something to accurately reference.

Where is the fuel leak at exactly? Is it leaking from a fitting and running down the pump to where it mounts on the block or the from the pump to block connection? If it is leaking internally in the pump (ruptured diaphragm) the fuel will mix with the oil and dilute the oil (not good). Does the oil smell like gas?

Post a couple pictures of the mounted carb and the attached linkages.
 
The fuel leaked directly around where it connects to the block. Old oil was checked, no gas in it. Changed the oil again, no gas in it. Changed the fuel pump, it didn't have a gasket but that wouldn't affect it if the diaphragm was ruptured. Who knows where that leak was coming from, it wasn't the fittings though. Now I have fresh oil, fuel pump, and did the fuel line change for good measure. No change to any of my problems though.

I can check timing chain. I've uploaded pictures as requested, including my lack of timing marks. Obviously I can imagine them and still see my timing wandering though.

Still hoping my carb is just in dire need of a rebuild. The car keeps running when warm when choked or on throttle, just wont idle.

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@Silum

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Hopefully I am leading you in the right direction and not hindering your progress. Anyone else feel free to correct me. The first picture shows that advanced timing is on the passenger side and retarded is on the drivers side of zero degrees. The third pictures shows where I measured from. There is a ‘cross’ on the timing cover, I measured from where the horizontalish cross intersects the passenger edge of the cover. The second pictures shows that 6-3/4” is about where 5 degrees advance is.
 
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That's perfect, thank you. I have enough to go on now to make my own out of cardboard, ha!
 
Silum said:
The fuel leaked directly around where it connects to the block. Old oil was checked, no gas in it. Changed the oil again, no gas in it. Changed the fuel pump, it didn't have a gasket but that wouldn't affect it if the diaphragm was ruptured. Who knows where that leak was coming from, it wasn't the fittings though. Now I have fresh oil, fuel pump, and did the fuel line change for good measure. No change to any of my problems though.

I can check timing chain. I've uploaded pictures as requested, including my lack of timing marks. Obviously I can imagine them and still see my timing wandering though.

Still hoping my carb is just in dire need of a rebuild. The car keeps running when warm when choked or on throttle, just wont idle.

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There should be a plug in the circled hole. It could be a manifold vacuum leak. Stick your finger over it when running and see.

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I won't lie, you got me pretty excited there, the prospect of a single bolt fixing my problem... i jumped out of my seat! Unfortunately I don't have any vacuum pressure at that hole and it doesn't seem to go anywhere. I plugged it with a bolt anyway and unfortunately there was no change, purrs when cold, dies when warm. Which begs the question... am I meant to have vacuum pressure there? What circuit should it be connected to? I'm still not beyond thinking I have a vacuum issue.

I will be refreshing the carb this weekend hopefully and I think I will see my fix there. Slowswinger, I have that very same vacuum kit and will try to include some readings when I put the carb on.
 
Silum said:
I won't lie, you got me pretty excited there, the prospect of a single bolt fixing my problem... i jumped out of my seat! Unfortunately I don't have any vacuum pressure at that hole and it doesn't seem to go anywhere. I plugged it with a bolt anyway and unfortunately there was no change, purrs when cold, dies when warm. Which begs the question... am I meant to have vacuum pressure there? What circuit should it be connected to? I'm still not beyond thinking I have a vacuum issue.

I will be refreshing the carb this weekend hopefully and I think I will see my fix there. Slowswinger, I have that very same vacuum kit and will try to include some readings when I put the carb on.
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I'm not certain. I just saw it empty and was hoping.
 
Have you checked to see that the hot air valve in the exhaust manifold is operating correctly? I also agree with what @pishta said. If you don't have inspection in your area, I would 86 every bit of that smog era stuff. There's absolutely no reason for it now other than to pass inspection. not saying any of that is the problem, but you'll never know with it all on there. Say for example, the EGR valve is not all the way seated closed because of carbon buildup. That's a manifold vacuum leak right there and one I've seen more than once before. I'd have a block off plate there in a Georgia minute. But again, non e of that may be the issue. It could be though. That's the disadvantage of online diagnosis. lol
 
RustyRatRod said:
There should be a plug in the circled hole. It could be a manifold vacuum leak. Stick your finger over it when running and see.

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Post #29. Thought it looked "pretty vacant" myself. I got 3 in the garage, 2 with...both are blind holes. Not there.....CA smog cut off is 1975 so he's clear of impossibly passing in a 1976 or newer carb motor here with all the visual checks. I had a vacuum hose that the guy didnt 'feel' was going to the right location (air cleaner snorkle shutter) and he didn't have a book on this Federal model. So he referred me to the (district) smog referee at a somewhat local community college, @ a 2 week appointment date (and extension), and the appointment was a 30 minute window in the middle of the F'n day that I could not miss or else I'd lose my extension and be open to get pulled over and towed. So the clown looks at it and says its a Fed motor (49 state) and writes it down on the form and then I bring up the fact that the very first smog attempt was waived off because the motor was over-revving at 25 MPH test speed (Documented...no F'n lie, the guy said I could not dyno test in 2nd gear!) and I asked him to explain HTF can I possibly pass if you (CA) wont test it in 2nd gear: its gearing, not smog equipment failing! He looked at me with the most condescending suck and slowly wrote a memo saying OK to test in 2nd gear. GD I hate this place when it comes to **** like this.
 
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Thats crazy, is that because you have a 76 or a newer Valiant? I figured that my 72 was exempt with the cut off so I could get rid of everything if needed, but I also know laws have been changed since I was last in this game. I do know my 72 is full of crappy smog equipment that they tried in CA, but I figured none of it is doing much harm either (well, maybe the smog pump).

To fill you in on my plans for this car, I am doing the Magnum 5.9/360 swap and have a collection of parts already. Your story scared me a little and I have visions of a smog referee taking exception to me. Ha.
 
Thank you to those sticking around and offering help!!

I cleaned out a rebuilt the carb... no change. :( Two things I found on my journey... one is that the fuel line going into the carb is slightly kinked, I can't see this being my problem as I can still rev to my hearts content and it gets fuel. Two, i'll show the picture of what a previous owner did to the check ball in the economizerr body. Again though, I'm not sure this is my issue, the check ball itself seems find and moves fine. This is mikes carb explaining the part that looks mangled: . Check the photo economizer to see what mind looks like.

So onto compression:
Dry they are 1-115psi, 2-118psi, 3-125psi, 4-125psi, 5-123psi, 6-115psi. My spark plug tube seals are all messed up and need replacing.

So onto timing and my actual questions for you all:
Answered my first question, crank moves twice compared to the cam. The timing still wanders 360 degrees with the engine on, why would it do that? I could show a video but it's not all that clear with the shutter speed of the camera, you can imagine a timing mark making its merrily way around though, appearing to rotate counter clockwise.

Next picture is of the rotor at cylinder 1 TDC, and spark plugs were wired correctly, with 153624 firing order. Does the rotor look correct to everyone else, it looks good to me but could someone verify? :(

What do I try next?

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^^ (rotor could be anywhere, depends on where the #1 tower is) if your timing is wandering 360 degrees (!) you sure its not 36 degrees? , that sure sounds like the friggin gear is no longer pinned to the shaft! be spinning balancer ring too.... that would surely prevent you from running, and starting it cold as the ignition timing would be so far off that it would not start. Advance plate not secured to distributor housing? Nothing makes sense that it would start up again cold and run. remove vacuum advance line and let it warm up without it (plug line so it doesnt become a vacuum leak) It should run at -10. Thats Limp home mode for a Ford EDIS.
 
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The rotor in the position shown is right where it was wired for cylinder 1 on the cap. Distributor vacuum is capped off during the timing test, though it does the same either way.

Could be my timing light I suppose. The physics of a timing situation where cylinder 1 is firing in various positions to the crank doesn't make sense for a car that idles relatively calmly at cold... and keep running when warm but choked.

I'm missing something. I can recheck my vacuum situation I guess elsewhere on the car.
 
I checked mine at TDC and the rotor looks pretty damn close to where your is. How did you verify that #1 was at TDC?
X2 on checking the distributor gear.
 
Slowswinger said:
I checked mine at TDC and the rotor looks pretty damn close to where your is. How did you verify that #1 was at TDC?
X2 on checking the distributor gear.
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I'll check distributor gear, but it's rotating normally, all are firing and in order.

It would have to be slipping somehow and then fixing itself for inspection. If the gear is not engaged I'd expect some other symptoms than struggling to run when warm right?
 
At this point you need to rule out as many things as possible. The distributor gear is one of them. Pull it out and take a picture of the gear and pin.
 
I dont think its the gear after thinking about it, it aint gonna 'heal' when its cooled down. I'm guessing the ring on the damper is moving but since you doesnt have a timing tab, your not going to have a reference to where to set it. Id suggest lining up rotor to #1 tower by hand (pull belts) and them taking white paint and marking a line on cover, through damper ring and down to damper hub, assume that is about TDC. That way if the ring is slipping youll see it move from the hub and cover mark. Only way you'll have a good idle is if the timing light is 'lying' by telling you its timed all wrong and wandering around. Dang, I even got a good damper here for ya. Id not concentrate on the timing as it sounds like its pretty close, its the hot no idle that stumps me without a vacuum gauge. if its a vacuum leak, you my be able to cover the carb with a piece of cardboard while its starting to idle like crap and see if it picks up. That would alter the A/F ratio.
 
Have you looked for a timing mark on the driver's side? That's where mine is......but it's a 64, a good bit older.
 
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