Great starting became hard starting.

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swifty said:
I think I found the problem. Was leaning out choke and hit the throttle to set choke and fast idle. When I looked down carb throat the secondary's were very wet. Car has been sitting for a few hours. This is vacuum secondaries and car has not been running. So I will take carb off and go through. I suspect the needle and seat are not sealing. Am I right thinking secondary's should be dry?
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Now after reading that, yes it could be the needle n seat.
Dual feed or transfer tube?
 
swifty said:
Picked up a half inch carb spacer to help with carb boil. Will pull carb off tonight and go through. I think I have enough parts lay in around to pretty much rebuild. I noticed some brown crap in filter. Everything on fuel system is new so I am thinking could of boiled off the fuel?
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Brown can come from gum build up in the tank, fuel deposits.
 
swifty said:
Picked up a half inch carb spacer to help with carb boil. Will pull carb off tonight and go through. I think I have enough parts lay in around to pretty much rebuild. I noticed some brown crap in filter. Everything on fuel system is new so I am thinking could of boiled off the fuel?
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New tank and lines too? The 'brown stuff' would not be from fresh fuel boiling off. Older 'gunk' is more likley, as MO sez.

BTW, consider a full heat shield, not just a spacer. The spacer does not prevent heat from radiating up from the intake and into the bowls.
Like this:
Holley 108-51: Insulating Carb Gasket Heat Shield Fits Holley Model 4150&#0153 and Model 4160&#0153 Square Flange Carbs | JEGS
 
Its usually the boring that goes bad.

JEGS 150249: Needle & Seat Hardware Kit Made in the USA | JEGS

What I have found is I'll go buy a $16 needle and seat from Holly just to have the thing flood my engine out a week later.... though when I pull it back out... it's fine except that O-ring. Save the money and just get the o ring kit if it looks good when you pull it and inspect it.
 
I would assume not due the different bolt patterns, and it does not look amenable to easy modification. Other have made their own from aluminum sheet and gaskets.
Thought you had a Holley? Future planning?
 
Pulled carb and took apart. The secondary needle and seat looked fine but put new one in anyway. Cleaned up everything and found the air bleeds on secondary were partially plugged. Cleaned everything up. Installed a 1/2" phenolic spacer with the 4 holes. Cleaned out fuel filter. Set primary transfer slot for a little past square. I then counted how far I can open throttle and be at .040. Put back to almost square. I then did not know what to do with secondary transfer slot. It was completely closed. I open it slightly but not up to transfer slot. Assembled everything. Set idle mixture screw 1.5 out. Cranked to fill bowls with no spark. Then gave it a pump and it fired right up. Idle about 1100. Let warm up and released fast idle. Died out. Opened idle screw to .040. Still to low to idle. Gave it 1 to 2 turns more and was enough to idle. Checked primary float and was fine. Secondary float was high so I cranked down a bunch. Tried setting idle mixture but screws did not do much left at 1.5 out. Vacuum is down a little about 17. Took for a drive and ran well. When I got back secondary float was low so set to just below hole. Shut off and car dieseled a little. I did not look at idle speed when I shut off. Waited a bit. Started right up. Idle was a little high, turned down to about 800. Turned off and was fine.

Messed around cleaning up. Checked a plug just for the heck of it. Tan to a little rich. Was a little lean before. Fired car up idled fine. Took for a short drive. Ran fine. I think the spacer helped the mid range but took a little off top. Came home and shut of and dieseled a little again. Temp was about 195.

So the starting problem seems fixed. Will see tomorrow on a primed fuel system and cold engine. Now the dieseling. Is it caused from to much idle and throttle being open too far? Where should the secondary be set with vacuum secondary and 2 corner idle? I was gonna switch to EFI this winter, but car is telling me now is the time. Plug fell out of bung when driving, carb issues. I just hate spend more money now and this is the best time of year for driving around here.
 
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Yes, the dieseling is often caused by too far open on the primary throttle. And if you had the primary transition slots exposed at all with the idle setting, that is too far open, and is probably why you lost command of idle mixture with the idle mixture screws. So yes, the primary idle stop was too far open.

The secondary throttle stop should be set by trial and error. It is set to make sure you have a good smooth transition, with no stumble, when you open the throttle enough to start to open the secondaries (which is usually a lot of throttle and RPM). It also effects the air into the engine at idle and very small primary throttle openings and thus effects off-idle transition stumbles, etc.

The common initial setting of this secondary stop is for the bottom end of the secondary transition slots being exposed enough to expose a 'square' shape. But you change it from there as needed for best operation. So if it runs well where you have it, then leave it there. Opening it a bit might help the dieseling; that I don't know for sure.
 
Car starts great again. I think it starts better when warm than it did before. I think I fixed dieseling problem. I gave it more timing 20. That brought idle up so I can reduce idle screw. Then I rechecked air screws and one was way out. Like 3 or 4 turns. Not sure how that happened . Put back to 1.5 out. Adjusted for max vacuum. Was able to reduce idle some more. Took for a drive and ran well. Also seemed to run a little cooler with more timing. Now to try to cool fuel line. I am getting boil in filter.
 
Sounds like good progress. Boil can be conducted heat but usually is heat radiated into the lines. Black fuel hoses are great at absorbing radiated heat so shield them with reflective foil or, better yet, replace them with metal lines that are reflective (silver zinc plated). Treat the lines this way all the way to outside of the engine compartment and anywhere near to the exhaust.
 
nm9stheham said:
Sounds like good progress. Boil can be conducted heat but usually is heat radiated into the lines. Black fuel hoses are great at absorbing radiated heat so shield them with reflective foil or, better yet, replace them with metal lines that are reflective (silver zinc plated). Treat the lines this way all the way to outside of the engine compartment and anywhere near to the exhaust.
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Gonna try insulating with some fuel line heat tube. Also try moving line around. I have ceramic headers so there is a good deal of heat under hood. Is there a safe way of running line outside of inner fender? Could try solid line up to carb.
 
Maybe if it was outside of the frame. But IMHO it ought to be metal up to the short rubber line that jumps over to the pump....

Silver shielding is the way... black shielding will just absorb heat and delay the heating process, not reduce it.
 
nm9stheham said:
Maybe if it was outside of the frame. But IMHO it ought to be metal up to the short rubber line that jumps over to the pump....

Silver shielding is the way... black shielding will just absorb heat and delay the heating process, not reduce it.
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Yeah I planned on having a rubber connection.
 
I also am looking for a heat shield for starter. Anyone use one they like?

I have a dodge Dakota starter and Doug's headers.
 
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Car started great today. Ended up being in a car show by accident. Went to check out and someone I knew flagged me over and the next thing I know I am filling out a form. Well first show . Now I have incentive to finish car.

Anyway car is starting great again. Will start new thread for heat related questions. Thanks for the help.

20180908_155406.jpg
 
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