Thoughts on stalling?

[Dick LeRoux]

You name it, & it's been done on my '63 Avanti R2658 & if you saw a '63 Gold Avanti stalled on 405 last Tuesday between Kirkland, WA & Woodinville, WA, that was me. After 15 months, of rebuilding it, the mechanic I worked with said it was road worthy & that he had it on the freeway with no problem. Stalled on me three times on the freeway within 10 miles & three times on surface streets. Gas tank cleaned, coated and all new gas lines installed along with new high octane gas with leaded additive. New fuel pump installed. New fuel filter installed. Carburetor over-hauled, re-built, cleaned & checked out. When it ran, it was pulling strong at ~ 3,000RPM running between 62 - 65 mph. Everything seemed fine, then it would just slowly lose power, & quit. I never strayed far from the shoulder so I would coast to a stop, wait, restart, & then I was off. Plenty of spark when I start it back up but currently it makes for a less than enjoyable ride. I'd appreciate any thoughts on where to start but it sure seems to me to be fuel related. Thanks as always for any advice.

[paul shuffleburg]

Sounds like it starving for fuel. I would check filter, then the pump and
then the float setting.

[TWChamp]

My 50 Champion did that and I found the tank liner coming off and plugging the fuel intake. Carry a spare spark plug with you and as soon as it quits just pull one of the plug wires and install the spare plug and lay it on your block to check for a hot blue spark while cranking. I always start by trying to see for sure if it's a fuel problem, or a spark problem.

My neighbor had his gas tank lined (against my advice) and the liner was coating the intake because it wasn't capped off during the coating process.

[8E45E]

If the fuel tank is not vented on an Avanti, make sure the cap is!

Craig

[BILT4ME]

Unless you installed an electric fuel pump, the fuel filter should be between the fuel pump and the carburetor, NOT between the fuel pump and the tank. What you are describing sounds just like a clogged fuel filter or not an adequate supply of fuel. It will work fine at idle, but as RPM increases and time continues at elevated RPM, the fuel supply will dwindle until it cannot run.

[mapman]

A combination of the suggestions would be to check to see if the tank has vacuum in it when it stalls by loosening the cap. If so you might have the vent blocked, possibly by the tank liner sealing the vent tube.
Rob

[Dick LeRoux]

New fuel pump from SI, not electrical, and the filter is between the pump & before the carb. There were two fuel filters & I removed the one between the tank & the pump. I mis-spoke (or mis-wrote) but the gas tank was NOT lined, just cleaned. It's the original gas cap with a new gasket. I was wondering if replacing the mechanical fuel pump with an electrical one might cure it. I've already lit candles but that didn't improve the situation. I'd sacrifice a chicken if I thought it would help.

[warrlaw1]

What Craig said. Drive a spike through that new gas cap.

[Dick LeRoux]

So if I drove it without the gas cap, that would do the same, correct? If that "cured" it, then I'd know in what direction to go. If not...

[warrlaw1]

Easy test. Git 'er done.

[Dan Timberlake]

I'd install a T in the fuel line at the carb and hook a 5 foot hose to the leg of the T. Then I'd run the hose thru a hood gap to a vacuum/fuel pressure gage taped to the windshield to monitor fuel pressure real time.

https://lh6.googleusercontent.com/-yYHqxnCWaJc/U5KsSULSgzI/AAAAAAAAFQQ/0R0kzvrw-Xo/s576/windshieldGauge.jpg

If the stalling occurs but the pressure remains OK then it is NOT a fuel delivery problem.

[karterfred88]

So if I drove it without the gas cap, that would do the same, correct? If that "cured" it, then I'd know in what direction to go. If not...

Yes, but I'd check the fuel hose between the frame and the fuel pump also. Maybe the right FI type hose was used, but if it has a kink in it, the fuel pump will suck it closed at the kink and do the same thing. But it sounds like fuel supply is the problem. If it does it again, pop the bonnet and move the throttle linkage to see if there is a squirt from the accelerator pump to make sure, no squirt, floats empty. Also check the hose from the tank to the line for kinks (I assume that was changed too). Change the new filters too if you can't find the restriction.

[StudeRich]

My question to you is: "are you SURE your 'Mechanic' understands the R1 & R2 Cool Fuel recirculating system"?

If there is not a .040-.060 restriction in the Tank Return line "T" or a Glass Bowl Fuel Filter with a restricted outlet Port, you are going to return TOO much Fuel to the Tank for proper running.

Also; if this is an R2, does it have the Supercharger to upper Fuel Pump housing Fuel Pressure equalization Tube?

[Dick LeRoux]

Rich, this is an R2 and now I'll have to check for the equilization tube. It's pouring down rain for next few days & I'm not taking it out in weather like this. It runs fine at idle and always starts right up but unless we have decent weather, I'm not up for being stranded in the rain. As always everyone supplies a wealth of information to neophytes such as myself. Thanks for the advice.

[StudeRich]

I am with you on that Dick, I am hiding inside from the Rain, right now myself.