New/Repro YF carburetor for the 300 six

Good idea! Glad you received yours, and it’s sounds identical to what I got. Three gaskets, but only one had the right spacing for the intake studs. It was packaged very well with model-specific foam shapes. I look forward to hearing how it works for you 🙂

Just following up this thread since I finally fired up this engine today.

I bought this carb on Amazon:

https://www.amazon.com/OCPTY-Carburetor-Carter-240-250-300-BARREL/dp/B084YWG1K2

It ran great right out of the box. I plugged the hot air port, and in the video below have the choke tied wide open. I didn't even touch the idle...nothing, it just ran. After a few minutes it would start instantly, and idle at 600 RPM according to the factory tach. Pretty happy with it.

That's great, Cory!  

Sounds good, Cory!

Anyone else get one of the 2 carbs used here?
It looks like I will be going with the ECCPP carb to replace the one on my truck as it is not working right at high way speeds.

I see Jonathan & Cory both use manual choke.
I can hook up the heat tube as I had to make one to work with the EFI exh. manifolds but have a question?

What if I was to take the electric part from my old carb and install it on this new carb do you think it would work like the factory wanted it to?
Dave ----

Choke caps are pretty much interchangeable Dave.

Mine came with a plastic cap over the choke lever, but there was no bi-metal spring or electric hook up. There has to be choke control, either manual or electric, and the supplied cap does neither. I assume this is just to protect the lever and mock up the retaining hardware, and you are supposed to install the existing control mechanism from your truck, whichever you have.

I imagine that eliminating the choke mechanism is a way of making these replacement carbs more universal.
And probably saves another $5 at the retail end.

Ford F834 wrote

Mine came with a plastic cap over the choke lever, but there was no bi-metal spring or electric hook up. There has to be choke control, either manual or electric, and the supplied cap does neither. I assume this is just to protect the lever and mock up the retaining hardware, and you are supposed to install the existing control mechanism from your truck, whichever you have.

I figured if I did not get any answers I would pull the cap and I would have seen it was gutted.
So I will swap my electric part onto the new carb.

UPS has the carb showing up around the 25th
Thanks
Dave ----

So this Amazon YF has been working well for the short little bursts that I've actually been able to run the truck. However, now that I'm able to drive the truck a little bit I am having a problem. It works great when it is cold (choke is tied wide open), but once the engine gets up to temperature the carb starts leaking terribly. I took it all apart thinking the float was stuck, or needle valve stuck, but it was all clean as a whistle. Put it all back together, and again it ran just fine while it was cold...but once it warmed up it started leaking terribly again.

This time when I pulled back up to my garage, it was leaking and I could hear the gas sizzling...on the intake and probably some of the exhaust manifold. It got me thinking though...am I overheating the carb somehow?

There is an valve in the exhaust manifold for heating the intake manifold...and I thought I tied it shut, but maybe I tied it wide open?

Any thoughts from the experts?

If it was a float or needle valve or fuel pressure issue, it wouldn't matter if it was warmed up or not, would it?

Right, if it was float level or pressure then temp shouldn't matter.

So it does sound like you may be overheating the fuel, causing it to boil.  I'd tie the valve the other way and see what happens.

Do you have any kind of insulator gasket under your carb?

It certainly sounds like the intake manifold floor is getting heat all the time.
Doesn't the exploded view show which way the flap below is positioned?

ArdWrknTrk wrote

Do you have any kind of insulator gasket under your carb?

Just the factory style gasket, which is an insulated one, but it just covers the perimeter of the opening in the exhaust manifold.

I'm going to try and flip the exhaust the flap the other way and see what happens.

I checked some pictures and videos of 300 exhaust manifolds, and it looks like mine is tied closed.

Are you sure the flap is still attached to the shaft, and not rotted through?

It seems odd that your carb would be getting that hot.
I don't think that is any fault of the carb.

I meant is there any insulator where the carb body attaches to the (non) EGR spacer.   ?

Jim,

That exhaust valve flapper was still intact and in good condition when I installed the manifolds, or at least it appeared to be. It has a counterweight on it to close it (on top of the thermostatic spring that was there), so I did have it tied in the closed position.

The only thing between the carb and manifold is a non-EGR aluminum spacer. The trucks never got the feedback carbs up here, but the earlier Bullnose 300's all seem to have EGR systems, while later on they just had spacers like this one (1986).

I was thinking back to the fuel pump...the one I installed was a higher pressure one, but not that high...and even if that was an issue, it should be cold or hot.

Googling around a bit I did find one guy that installed a thicker gasket somewhere for this same reason, and cured it.

The temp gauge on the truck stays pretty low, so I don't know what temperature it is actually running at.

Looks like the float was the culprit. I don’t know how the temperature affected it, but the Amazon carb had a plastic float in it. I swapped in the metal float (which had more heft to it) from the original carb that was in the truck (an original YF that had been reman by Autoline p/n C6077.) works great again, and no leaks. Carb is cold to the touch even when up to operating temp. Thanks guys for listening to me whine LOL.

Interesting!  I would never have guessed that the temp would affect the plastic float.  Obviously it must be made out of the wrong material 'cause billions of plastic floats don't have that problem.

I wonder if it is expanding with the heat?  But that would seem to mean it would float easier and lower the fuel level and this would suggest the fuel level was going too high.  

Well, I'm glad you've got it figured out and it was an easy fix Cory!  

If it was a common problem you'd think it would appear in the Amazon reviews.

I've seen 'waterlogged' foam floats before. But it seems this is not that.