mauls

The jetstar has been running great since the 425 swap. Drove it to work Yesterday, topped off the fuel tank and it drove fine to work.

One the way home from work, I had just got on the HWY, left lane and it cut out, acted like it wasn't getting any fuel. The car died and I had to weave through traffic to get to the right shoulder while the car was dying.

I know these are hard to trouble shoot without looking at it. But I pulled the air cleaner and looked at the carb, it appeared to still be getting fuel. Had spark etc. No fluids leaking under the car, car was right at 190 deg

Checked all spark plug wires, all other electrical wires and everything was solid.

My only guess is maybe the fuel pump is weak and going out?

Do you guys have any suggestions of what else I should look far. The car was towed home to my garage.

cutlassjoe

Maybe getting too much fuel, like the float may be sticking a bit. Could you see if the carb was damp where the gaskets are.

mauls

Yes the carb was damp, wasn't saturated though.

BTW i'm running a Holley 630

Edit, I'm sorry I misread, the carb was dry around the gaskets

joe_padavano

If there's fuel in the carb (you see a pump shot when you move the linkage) then the fuel pump is unlikely to be the problem. A temporary fuel pressure gauge installed at the carb will verify this.

I hate to say this, but you may be the latest in the timing chain epidemic. If fuel pressure is good, throw a timing light on the car and watch the balancer while cranking.

mauls

When I move the linkage I can see the fuel pumping in there fine.

Didn't even think about the timing, I will pick up a timing light tomorrow at the auto parts store.

Thanks Joe for some idea's

Texas Jim

Just wondering, how do you know that the spark is good? Do you mean that you saw a good spark jump from end of wire to metal, or w/ plug in ign. wire, you saw spark in the plug gap? From my experience of years ago, the old coils go out sometimes, and you could just pull the coil wire and see if it's firing.
Joe, you're giving this guy "nightmares." LOL! The timing chain??? Oh no!!! LOL! Check the spark, as I hope that Joe is wrong. Hopefully your coil went out. Just a guess ofcourse. But I have to say, Joe seems to know his stuff. I'm just saying, I'd check the simple stuff first.
Those two cars you have are great! You have great taste in cars and they remind me of the better days in my life, as a younger guy w/ less responsibility. I love the kids more than I loved my younger days, but it's fun to remember having a ball w/ the fellas and girlfriends.
Good Luck. Hope it's an easy fix.

mauls

Thanks Jim for the kind words

The car started up today and ran fine for about 10 mins. I was able to check the timing and it was fine. I'm thinking It's a carb issue. It seems once the car warms up to 190 deg, is when the issue starts to happen. I think it may be getting to much fuel and flooding itself out.

Strange how it just happend while I was just out for a normal drive, maybe a piece on the carb broke off or is gummed up.

The motor has a new HEI, new plugs, wires, I bought the carb used and have only put about 100 miles on it. I will focus my attention on that unless anybody else has any other suggestions.

Oldwolf

Take of the fuel tank filler tube cap, just maybee it´not ventilating enough (sealed up), and that would prevent the fuel going to the carburator., just a guess but it´s happend before.

Stanley

Higgins

I got some bad gas one time, had water in it. I never get gas at a station if the delivery truck is there. They stir up whatever is in the bottom of the storage tank. Might check your gas for water in it if you filled up lately.
Higgins

mauls

Never thought of the bad gas issue, I just filled up that morning, should I just throw some stabil in and see what happens?

Rickman48

Think I'd be filling a coffee can w/gas from the line and pump, after adding the Stable.
It'd tell you if there's water, and get the 'good' fuel to the carb faster!
From your description, I hope that's your problem!!

X2 on no gas during a tank fill!

oldcutlass

You can buy stuff called gas line antifreeze or dry gas, basically it has alchohol in it. Mixes small amouts of water in your tank with the gas. What I would do first is get a sample pf fuel from the fuel right when the car quits, and litmus test it for water. Sometimes if there is enough water you can see it seperate in the jar. The water will be on the bottom as its heavier than gas.

MDchanic

With HEI, it's aways possible that you've got an intermittent in the coil or the module.
You'd need to check the spark WHILE the problem was occurring - it could return to normal and start right up, and you'd never see anything wrong.

If the problem only occurs on the highway, while you're going at a good clip, then consider the coil or the module (especially the module) the fuel pump, or a restricted fuel line or filter.

- Eric

Higgins

Not sure Stabil will do much for you. If it is bad gas you need to find out by getting a sample as Rickman suggest. If you find out it is bad gas & have the receipt, the gas station should cover the expense.

MDchanic

You're kidding, right? :rofl:

- Eric

Rickman48

Must be - while a Manager @ Tuffy's in Lockport, we had 5 customers come in from the same Speedway down the street - cars wouldn't run!
ALL fuel samples were GREEN - someone had put diesel in the regular tank!!!!
They came and got the samples, said it was normal, and wouldn't pay **** for their repairs!
Kinda why I never by off-brand fuel, ever!

TripDeuces

Being you stated it happens when the car warms up I'm leaning toward electrical issue. It's an HEI? Do you have a dedicated 12v going to it while running?

Guy who owned my car before me put a Mallory Unilite in the stock distributor. I was always wondering why there was a ballast resistor on my firewall (ceramic block type). I downloaded the directions for the Unilite on line and it says you needed a resistor inline for it. What the idjit before me failed to realize is these old cars have resistor wires (for the most part). My ignition was getting double resisted and when it got HOT the resistance went up further in the wires and the car would shut off. Leave it sit for half an hour and gtg again.

Maybe you just have a bad component in the HEI, like the ignition module (common if it's a cheap aftermarket one). The Delco ones are the best along with Performance Distributors (Davis Unified)

Higgins

All I can relay is my personal experience. My girlfriend, at the time, had a fuel injected Toyota and got bad gas, water in it, at a TOTAL station in Colorado, where I lived at the time. They paid for all the repairs.
The time it happened to me, it was just 3 gallons of Mobile in a commercial lawn mower so I didn't persue it. The mower had been running perfect until I got the gas. I drained some out into a glass jar and let it sit for a while and you could see the water in it. Drained it out, put fresh gas in it and it ran perfect again.
Speedway is Marathon. They have hundreds of stations here in Michigan.
I'm sure they wouldn't volunteer to pay for it unless you pursued it. Bad gas may not even be the problem, just a possibilty that's easy to check.

Texas Jim

So I see you have an HEI. Still, after getting to operating temperature, that's when "shorts" occur. Electrical components break-down after getting warm, epoxy/insulation... The one post was right, to check the problem out-w/ a multi-meter-when it occurs, otherwise you'll see no indication of a problem. I'd dive into the electrical system. Only my opinion. Best of luck w/ that beautiful ride.

Jim68-442

I would lean towards electrical as well. The car runs till you reach a higher temp.
Had a sim problem. All it happened to be was a bad connection. Car ran fine till it reached a certain temp and then would stall. After 15-30 min of cool down it would run for another 20 min till temp would rise again ,and then repeat. wasted weeks of time with checking carb, fuel, spark, never accured to me a loose slitely corroded connection end. Good idea to start off checking the things u did . Just from past experiance i would lean to electrical at this point.

mauls

Gonna give this a shot as well. My electrical system is very sketchy, it was that way when I bought the car. It needs some TLC for sure.

gonna go an easy route real quick check the fuel filter as well. Will report back

Tahnks

TripDeuces

Thought of another idea. Your car has an HEI? Is it a full 12v going to it while running or is it powered off the resistor wire? I know some GM 65's came with a resistor ignition (key) switch rather then a wire. You have to bypass that and make sure a full 12v is getting to that HEI while running.

I didn't see if you said you have an HEI or not but if you do this is valid.

67442nut

I've had a similar problem before.
It would be running fine and then just suddenly stall and wouldn't restart until later.
Turned out it was a bad coil wire.
It was one of those random things that was hard to diagnose because it was intermittent.
When it finally wouldn't start at all, I was able to track it down to no continuity in the coil wire.

mauls

coils are fine, timing is fine, getting great spark, has plenty of air. My only idea is bad fuel pump / filter

The car set for 14 years before I bought it. After the new motor build, I ran some seafoam in it added gas and just went. I'm guessing the gas broke loose rust in the tank which clogged the fuel filter

mauls

Finally solved the problem, the fuel filters were clogged with rust, I replaced the fuel pump also.

Rear Filter


Front


All the debris I knocked out of it


I'd hate to see the inside of my tank, I guess I'll be on the watch for a OEM fueltank, and replace the lines as well. If not I feel this will be a recurring problem.

TripDeuces

Funny, this exact same thing happened to me last year. Was so packed with rust I couldn't even see the filter. I think it's time I get a new gas tank I removed the filter in the carb and put an inline see-through filter on it that was bigger so I can tell next time. It's not my ideal setup but I have to live with it for now.

mauls

Yeah it all makes sense now, The same morning it broke down I topped the fuel tank off, which I'm assuming it broke all the old rust free at the top of the tank and sucked it through the lines, I'm just glad it wasn't anything major with the engine, I just had it rebuilt

projectheaven

where exactly did those fuel filters come from on the car?

MDchanic

That's the factory sintered bronze filter from the carburetor fuel inlet.

- Eric

projectheaven

Oh ok.
Thanks