timothypaul

Hi All, I have a question. Was driving my Olds the other day to the market and it ran fine. I parked it and went into the store. I came out, and it was a little tough to start - like it wasn't getting gas. I chilled for a minute or two, and tried again, it started right up.
About 5 minutes later - it did a burpie type thing and hiccupped, then it just cut out on me. I coasted into a safe area and shut it off and called a tow truck. Forty minutes later, when the tow truck got there, it started fine and he was able to drive it up on the ramp with no issues. I didn't want to risk driving it back to my place because if it happened again, there would be no safe place to pull over. When we got back to my warehouse, he started the car, drove it off the ramp and into my warehouse bay with no issues.

I am thinking perhaps the float got stuck? I've never suffered from a vapor lock issue before - so not sure what that would be like. I have a manual choke on the carb, and that was fine. I don't want to take it out and have it die somewhere. The carb was done by Cliff Ruggles a few years back, and has been flawless since I installed it..

Any ideas?...

Thanks...Tim

Vintage Chief

Belching & burping could be a couple of things. You're correct in assuming it might be the float, but it might be the accelerator pump, also. The easiest to quickly check which could be the issue as well is to remove, inspect &/or replace the fuel filter. Look for signs of contamination in the fuel filter.

Olds64

Tim, did Cliff install the manual choke for you or did you do that since Cliff rebuilt it? It's not unheard of for a carburetor to need another rebuild after a few years. Do you have a mechanical or electric fuel pump?

droldsmorland

At first glance, it sounds like a combo of heat soak and today's shizt fuel.
How does it perform under hard acceleration warm and hot at WOT?

Step 1. Check all the simple items...
a. choke setting,
b. replace carb fuel filter, (as VChief said),
c. carb to intake tightness and the carb assembly itself for tightness. Check the carb to intake gasket. All of this is easy now as the fuel line is off for filter R&R.
Careful it's easy to overtighten all carb fasteners and filter inlet thus damaging/wrapping the carb. If you do replace the carb intake gasket check it again for tightness after 500-1000 miles as the gasket will settle.
d. vacuum leaks. A vacuum gauge is your friend for tuning & tbl shooting. I rarely use a timing light.
e. all rubber jumper sections in the fuel line. Older than 10-15 years, likely needs attention.

Step 2. Move on to more complex items... verify fuel pressure, timing and whole ignition system condition & settings.

Step 3. Clean/Rebuild carb.

Step 4. Eliminate the heat soak if this is the root cause. Install carb base insulator(see c above), plug exhaust gas heat riser crossover in the intake. Install integral electric choke if it has the divorced type.

Step 5. When root cause is found please report the fix to close this thread.

timothypaul

Hi Jesse - no, actually Cliff sent the carb back in 10 million pieces and I had to reassemble myself. I'm actually pretty good with Q'Jets so it wasn't a big deal for me. He sent it back with an electric choke, but I decided to go manual. I just recently replaced the mechanical fuel pump. My only weakness on Q'Jets is understanding the metering rods... so when I was working on the carb, i experimented with three different sets Cliff sent out. Still not sure if I am happy with my current choice. I was actually thinking it could be that. My workbench has been a huge mess lately and I haven't felt like cleaning it so I have a nice area to pull the carb apart. lol - maybe this is the incentive.....

drolds - excellent points. I have been messing with my vacuum lines recently, I did not think of that. It started to get a bit cold down here in Florida, so I hooked up my heated control valve. Perhaps I did a crappy job.I will double check that later today, or actually probably disconnect it. I believe winter is over here in Florida. What is "heat soak" ? Also, yes - I have not checked the carb to intake in quite a while. I can pop a new gasket on.

Vintage Chief

I don't believe you want to overthink this - which becomes easy to do. Re-reading your first thread, then reading your follow-up thread, I could easily assume the plot thickens. But I suspect, in your case, the plot really does not thicken if what you stated in your first thread is true:

1) If the car was running fine - I would not suspect any of the metering rods are suspect (unless you accumulated some rat turds in the metering rods orifices during the time you went indoors to shop).

This just sounds like it could be basic stuff. Start w/ the fuel filter R&R. Tighten up your carburetor bolts so you're not introducing external air and the carburetor gaskets are doing their job. If your carburetor gaskets are soaked w/ fuel, consider changing them. Be certain to adjust your A/F mixture screws w/ a vacuum gauge. Run each one in & out until you achieve maximum vacuum (which should be ~17"Hg).

Start simple - stay simple until you can identify a true issue. But if this car ran fine I don't suspect it's going to need a complete rebuild after only three years of operation.

drolds is referring to fuel boiling in the carburetor I believe.

Greg Rogers

I think that usually a carb problem doesn't just quit. It will run poorly and maybe restart, smell like gas, etc,etc. But if your car just plain quits, and then restarts later and again quits that sounds like ignition to me. Do you have HEI or pertronics, or still points? If HEI I would look at module or pickup coil problems. Especially modules will quit when hot then work after cooling on and on. If it happens again check for spark right then while it won't restart. Good luck, let us know what you find..

droldsmorland

Heat soak occurs when the engine is shut off from a full temp run.
The underhood temps spike and will boil the gas in the carb and possibly the lines and pump.
In 1970 the gas was a different mix compared to today. Today the gas can tend to boil at a lower temp. Thus something that wasn't a problem in 70 is in 2020.

Blocking off the heat riser ports in the intake and installing an insulator gasket under the carb fixed it for me.
I also installed a heat shield on the starter, HD truck starter solenoid on the OEM High toeque 442 starter, new starter cables and wrapped the exhaust head pipe by the starter.
You dont need this unless you run into starter troubles

Another tuning tip is to pull the plugs and read them. Black Tan or white? (Rich, OK or lean).