Carb Problem - So frustrating!

[Bill M.]

Re: Carb Problem - So frustrating!

Bill in the last 3 years I have changed pumps on my 65 and 67 C60 bothe were replaced from under the car I have a lift so they were not to difficult. I bought the pumps at local mom and pop parts store.

[William G.]

Re: Carb Problem - So frustrating!

Does anyone know if there is a reproduction pump that will pass NCRS judging? If I am going to have to change the pump, I might as well change it to something that will pass judging!

I am using a later non OEM Holley, as mentioned in one of my earlier posts. I am using the front original style primary bowl, so as to use the original fuel line.

Years ago, after storing the car over the winter months, I pulled the original date coded carb off and took it apart. My heart sank when the inside of the thing, behind the metering block and metering plate had been turned to black powder, apparently from the alcohol in the fuel! I figured the carb was junk, but kept it. In 2018, when I decided to put the original engine back into the car, I sent the original carb to Chicago Vette and they were able to remachine the surfaces and rebuild it. I am now protecting that piece like it is gold! Hence, I am using the generic Holley to be able to drive the car and not worry about fuel damage, should it happen again. When I know the car is not going to be run for a while, I do remove the carb and drain all of the fuel out of it, as well as behind the metering block and secondary metering plate. So far all has been good doing it that way. I am taking everyone's advice here and will replace the fuel pump, as that is the only link in the fuel system chain that has not been touched since the engine was reinstalled. I do not remember how old the pump is, but my guess is it has been used for a long time on both this engine and a 350 ci I built and used for a while.

Bill

[Richard M.]

Re: Carb Problem - So frustrating!

Bill, Yes Holly had a serious issue with their castings disintegrating from ethanol in certain years. I recall they had something on their website about it, or I read it on another forum.

So I must say, if me, I wouldn't swap out the fuel pump just yet. It's not the preferred "diagnostic" method. Plus, you could be adding another potential fault if something happens afterwards. These days one has to be very careful with replacement parts.

I'm not saying the pump is either good or bad because we don't know what the actual pressure is.

In Patrick's case, he didn't bother to do a pressure test because he saw it leaking out of the pump itself.

I'd go after this original problem using a more methodogical approach.

Test what you can before swapping things out, effectively guessing. If this means opening the carburetor again, this is what I would do.

Rich

[William G.]

Re: Carb Problem - So frustrating!

Hey Rich,

Thanks for your input. I will be going through the carb again to make sure I didn't miss something with the float. However, in all of the years I have worked on this car, other than having the hinge pin fall out and the float floating away, ( this happened in a former float bowl when I had a guy "professionally rebuild" the carb. Whatever he used to soak the bowl, caused the interference fit pin female hole to enlarge enough to let the pin fall out. ) I have never had this type of problem with any carb. My carb is doing the same thing as Pats. The fuel is coming out of the vent hole in the top of the float bowl!
The fuel pump is the only thing in this fuel system that has not been replaced. It is not an expensive part, so if I don't find anything inside the carb that would indicate where the problem is, then my instinct would tell me that something inside the pump is causing the problem. I just don't have a pressure gauge, or know anyone near me that might have one! Heck, where I live on the east coast of Florida, there is not even a Corvette shop near me, or to my knowledge, a classic car restorer!!
Before I found the gas tank all rusty, the car had run fine andI was not having a flooding issue. This has only happened after last driving the car, so maybe the same thing that caused the fuel tank to rust, is now causing the pump to not work properly!

Bill

[Richard M.]

Re: Carb Problem - So frustrating!

Bill,

I didn't know you're in FL. I just looked in your profile and see your phone#. Is that # still good? I'm in a little town just north of Sebastian, about half way between Melbourne and Vero Beach. You?

Your '67 has AC? Argh! Fuel pump is fun on a AC car.

Got lift?

If you'd like, and if we're in close proximity to each other, and it turns out your fuel pump is definitely toast(I have FP test stuff), I have a few options to consider.

I have a car trailer(enclosed), and a lift in my shop, and tools, and a little time between packing for a move. I'd offer this, all gratis. (and we could talk all we want about our stenosis in the comfort of my air conditioned shop too, offline!)lol

I'll call you later this morning.

Rich