Tri-power issues

[KULTULZ]

Now to find someone who has the skills to correctly machine the main body of a carb. Any thoughts?

- https://www.corvetteforum.com/forums...ng-blocks.html

- https://www.holley.com/blog/post/how...ey_carburetor/

[Jeff Norwell]

I would speak with Drew Pojedinec, runs Air Fuel Spark.... deals with every Ford carb made.Holley Specialist...
He is very good.... and I mean GOOD.


https://www.afscarbs.com/?fbclid=IwY...98XX6vFMI_pGdg

[SoCalCoupe]

Originally Posted by Jeff Norwell

I would speak with Drew Pojedinec, runs Air Fuel Spark.... deals with every Ford carb made.Holley Specialist...
He is very good.... and I mean GOOD.


https://www.afscarbs.com/?fbclid=IwY...98XX6vFMI_pGdg

Thanks for this great referral. Checked it out online; didn't know someone like this existed. Will definitely give him a call.


Although the seller of this car, 18 months ago, claimed that the carbs had been rebuilt; a more accurate report would have been that some imbecile with a hammer and a screwdriver who couldn't count to four hacked away at the carbs while he owned it. I now see what a total mess they are and am too slowly analyzing and recovering. Should have paid much more attention in the beginning.


Hope I don't have to do an engine rebuild from all the raw gas these things have been pumping through.

[KULTULZ]

Originally Posted by Jeff Norwell

I would speak with Drew Pojedinec, runs Air Fuel Spark.... deals with every Ford carb made.Holley Specialist...

He is very good.... and I mean GOOD.

https://www.afscarbs.com/?fbclid=IwY...98XX6vFMI_pGdg

... damn! ...

ALSO - https://www.ford6vcarburetion.com/home/joe-bunetic/

[alt63bird]

Originally Posted by KULTULZ

... damn! ...

ALSO - https://www.ford6vcarburetion.com/home/joe-bunetic/

Joe Buentic passed away earlier this year (March, I believe). I second Jeff's recommendation for contacting Drew at Air-Fuel-Spark, but be aware as often as he's out to sea, and with all the Facebook posts and emails he gets, he's very particular as to how he responds to inquiries.

BTW I'm trying to find a spare secondary C1AE-AV carb and got a PM in response to a Barn 'wanted' post from a guy calling himself 'cutoff' who just joined the Barn a few days ago saying he had one. With only 10 posts - most of them 'test' messages, I'm real suspicious it could be a scammer since he wanted my phone # for texting me info. As Ronaldus Magnus said, "Trust but Verify."

[SoCalCoupe]

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Originally Posted by alt63bird

I second Jeff's recommendation for contacting Drew at Air-Fuel-Spark, but be aware as often as he's out to sea, and with all the Facebook posts and emails he gets, he's very particular as to how he responds to inquiries.

I sent Drew a pretty detailed email—he replied. I was hoping for a limited rebuild on the center carb, but he prefers to do all three or none. I understand that; I’m self-employed in a service field too, and sometimes selective jobs aren’t worth the time or hassle.


I’m sure he could restore the carbs to factory spec, but like others have said in this thread, the real issue seems to be heat—fuel is boiling over, and a factory rebuild won’t solve that.


I’m now less than 75% convinced my warped main body was the culprit. I carefully filed a couple of high spots—took off very little material—and it sealed fine, so I'm confident to move forward.


I just ordered about $250 in parts, including phenolic spacers. Nothing off-the-shelf fits exactly, so I’ll Dremel them to match. Found enough small issues I can fix to justify seeing this through before jumping to an extremely pricey tri-power EFI system.


One of the missing parts was the center carb’s fuel bowl vent baffle. Installing that might help a bit.

[SoCalCoupe]

Originally Posted by alt63bird

BTW I'm trying to find a spare secondary C1AE-AV carb and got a PM in response to a Barn 'wanted' post from a guy calling himself 'cutoff' who just joined the Barn a few days ago saying he had one. With only 10 posts - most of them 'test' messages, I'm real suspicious it could be a scammer since he wanted my phone # for texting me info. As Ronaldus Magnus said, "Trust but Verify."

I’m always happy to exchange ideas with new members—but I don’t do transactions. Ten posts? Fuggedaboutit.


For what it’s worth, I tried to sell a car on Cars.com a few months ago and got hit with a classic scam. I still have the fake cashier’s check:
– The name didn’t match the buyer.
– The address was from one state.
– The routing number was from a different region.
– The phone number that texted me traced to yet another person in yet another state.
– And of course, the check was for “just a little extra to cover shipping.”
Luckily, I’m skeptical by nature. I didn’t deposit the check—just reported the whole thing to Cars.com and walked away.


Scammers are getting clever, but the red flags are still there if you’re paying attention.

[Rice]

I appreciate the updates. Thanks

[SoCalCoupe]

Can't fit more than 1/2" spacer and still close the hood. The only 1/2" spacer I can find is aluminum. Doesn't seem like there's much point in an aluminum spacer is insulation is the goal. Thoughts or alternatives?

[miker98038]

It used to be common to make a spacer out of hardwood or phenolic. Just trace from the gasket. Now mostly done for older carbs. Not difficult, just a bit time consuming. A coping saw and a drill will do it. A drill press is easier.

[KULTULZ]

Here are two choices -

INSULATING SPACER KIT - https://hotrodcarbs.com/store/holley...nsulating.html

INSULATING SPACER KIT w/ CARB FUEL BOWL SHIELDS - https://www.hotrodcarbs.com/store/ho...1/2-thick.html

[SoCalCoupe]

Here’s where I’m at: I did an amateur rebuild on the carbs, but the same problems persist. I did manage to reduce some warpage using a file—carefully—but I now don’t think that was the core issue.


One thing I discovered: these carbs should have fuel bowl vents, but they don’t. I plan to fix that, and I think it could help with the hot start problem. I also added spacers that fit under the hood.

Idle speed and mixture are now adjusted pretty well. The car’s a 4-speed, so automatic transmission gear lever position isn’t a factor. In the driveway, everything seems fine—throttle response is good, idle is stable and blipping the throttle everything seems fine. But on test drives, when I push in the clutch, the engine often slows down and dies. If I try raising the idle speed to compensate, it holds a good idle in the driveway—but then during a test drive, it won't return to idle and just races at 1500–2000 RPM.


It’s maddening. I don’t think this is an ethanol issue. I suspect it’s a transition circuit problem caused by opening the throttle blades too far to achieve idle.
(Quick recap for those less familiar: a typical carb has five fuel metering circuits—idle, transition, cruise, power, and accelerator. The transition circuit bridges the idle and cruise circuits. It’s controlled by a slot in the venturi that gets progressively uncovered as the throttle blades open. If the blades are already too far open at idle, the transition circuit is compromised.)


I had a similar issue years ago with a Chevy running a low-vacuum, high-duration cam. The fix there was to drill small holes in the primary throttle plates to allow more air at idle without opening the blades too far. That kept the transition circuit working properly, and it worked great—but that was a modified engine, and I eventually sold the car (but regret it).


Now here’s the thing: I’ve run a bunch of AI queries on my Galaxie setup, and it keeps recommending the same fix—drill the throttle plates. But I’m hesitant. That fix made sense for a modified engine. This Galaxie is (supposedly) a stock 406 with a stock cam and stock carbs. I shouldn’t have to modify things like that. I can't say for sure the cam hasn't been changed at some point, but everything seems stock.


Any thoughts on how to pin down what’s causing the inconsistent idle return and/or stalling while driving?

[Gene F]

Or the power valve was the wrong size to start with. The heat spacer...if necessary stack up mounting gaskets.

I assume you solved your machining need, so I won't even go there.

[SoCalCoupe]

Did some more troubleshooting. Disconnected the PCV valve, maybe a slight improvement, or maybe it was just wishful thinking. Used lots of carburetor cleaner spraying carburetor cleaner everywhere looking for leaks. Nothing.


Now that I've disconnected the PCV valve, I have a place to connect a vacuum gauge and REALLY dial in the carbs.


Learned something new, air is sucked in through the choke tube. I'll check that area of the carb specifically for leaks and proper gaskets where the choke housing connects to the carb. Don't think that will make too much difference though.


Had a thought, maybe it's ignition and not fuel. What I'm hopeful about now is looking at the distributor mechanical advance. (There is no vacuum advance.) A sticking or lazy return mechanical advance would cause exactly these problems. Did an AI search and found that "[t]here is considerable history and ongoing discussion about mechanical advance issues—specifically, sticking or lazy return—in early 1960s Ford V8 distributors. The mechanical advance mechanism in these distributors uses weights and springs to advance ignition timing as RPM increases. Over time, these weights can become stuck due to rust or debris, or the springs may weaken or get gummed up, which can cause "lazy" or slow return to the normal (retarded) position once RPM drops."

[Gene F]

SoCalCoupe, you may be onto something. That choke tube in a lot of cars is supposed to draw in a small amount of exhaust gas from the exhaust manifold to heat the choke coil. Certainly for the purposes of diagnostics it will be good to plug that.

Advance may be a significant issue, so keep working on that

[dmsfrr]

Originally Posted by Gene F

SoCalCoupe, you may be onto something. That choke tube in a lot of cars is supposed to draw in a small amount of exhaust gas from the exhaust manifold to heat the choke coil. Certainly for the purposes of diagnostics it will be good to plug that. ...

Heated air, Not exhaust gasses. Depending on the year & style intake manifold there is a choke stove on, or a heat exchanger tube in, the intake manifold exhaust crossover or an exhaust manifold.

Only heated air is drawn into the choke mechanism. If exhaust gets into the choke thermostat it can be quickly ruined.