64 Riv 425 w/ dual 4's won't run

[sparkmanttx]

I have a 64 Riv 425 w/ dual 4's that has been running great and all of a sudden it has developed a problem. It will start and run just fine for a few miles and then it will quit and acts like it isn't getting gas. We checked the fuel pump pressure and it is approx 9 PSI. Put on a new fuel filter with no improvement. When it dies it won't start at all. Just cranks and feels like there is no gas. After sitting overnight it will start right up but won't stay running. I have let it sit and idle and it runs just fine. Any suggestions.

[JohnD1956]

If the milage is between 90 and 110K, AND the timing chain and gears are original, then this is where I'd start. The parts are usually available and rather cheap. Good luck.

[Guest simplyconnected]

Is the fuel tank and pickup original? If it acts like it is starved for gas, it probably is. My '55 did the same, ran just fine until the pickup got clogged, then nothing. When the remaining gas back-washed the pickup screen, it would clear until next time.

After dropping the tank, I cut a hole and pulled out five handfulls of rust. The new tank (with new pickup and screen) seemed expensive at the time. Now I realize how IN-expensive the new tank really was.

Timing sets don't heal themselves. When they jump a tooth, it's off forever.

If your spark is wrong, you will usually smell plenty of raw gas. The absence of that smell will usually tell you that fuel isn't being delivered to the carbs. Use all your senses. Pour a little gas in the carb, and see if it starts, even if it rus momentarily. If it does, start at the filter, fuel pump, and work towards the tank. Dual quads like lots of fuel, so make sure you have lots of flow.

Hope this helps. - Dave

[JohnD1956]

Lots of good advice. I would add that I personally have never seen a timing chain jump a tooth on a Buick. I've seen them stretched so that the car would start cold but die as soon as it warms up. This would be in a few minutes time of running. I would also add that on every single Buick I've owned, and this is around 7 cars, I had to change the timing chain and gear set at the milage I indicated above, with the exception of my 56, which has metal gears from the factory. Even so, I did change those at 120K or so.

Still I agree with you Dave. When it dies, dump a bit of gas down the carb and see if it fires up. If it does, its probably not timing chain related.

[Guest simplyconnected]

John De Fiore, changing the timing chain is a very wise suggestion for an older engine. GM has had rather odd standards regarding their timing chains. In the early '60's all the gear sets were metal. When Pontiac had a '61 4-banger Tempest, it came with a heavier chain than the 389's. (All the racing guys used that one.) Then in the '70's, GM molded nylon teeth over aluminum for the cam gear. My dad's gear came apart, causing thousands of dollars in repairs because the pistons tried closing the valves with little success.

Today, I use ONLY steel timing gears and a good roller chain. It's cheap insurance and the engine runs so much 'tighter' for a lot longer.

[The Old Guy]

I have run into this before, and usually it is the filter in the tank that is the culprit.

[Guest simplyconnected]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: The Old Guy</div><div class="ubbcode-body">...usually it is the filter in the tank that is the culprit. </div></div> I totally agree, because it gets loaded with rust and debris.

[Guest rlbleeker]

When it dies, take the air cleaner off, look straight down the carb and open the throttle. You should see jets to fuel spraying from the throttle pump. If you don't it's fuel supply.

[Jim Cannon]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sparkmanttx</div><div class="ubbcode-body">I have a 64 Riv 425 w/ dual 4's that has been running great and all of a sudden it has developed a problem. It will start and run just fine for a few miles and then it will quit and acts like it isn't getting gas. We checked the fuel pump pressure and it is approx 9 PSI. Put on a new fuel filter with no improvement. When it dies it won't start at all. Just cranks and feels like there is no gas. After sitting overnight it will start right up but won't stay running. I have let it sit and idle and it runs just fine. Any suggestions. </div></div>

Are you still running stock points ignition?

[Guest brh]

I'd go the route of a little gas down the carb, but above all while playing around with a fuel problem don't forget your fire extinguisher!!

[NTX5467]

I concur, timing chains don't "heal", they stay broke. In the times when those and later GM engines were in production, it seemed that when a timing chain "went", it was usually in the 80K mile range. A friend had a BEAUTIFUL black '73 Riv whose timing chain went one night. When trying to start the engine with a jumped timing chain, there's usually some backfiring and poor running. Advancing the distributor one plug wire notch might at least let it start, if there is no other internal damage.

Unless the points have slowly regapped themselves due to wear, I don't really see that as a culprit, but it might be a contributing factor to flaky driveability.

My '68 5467 had an issue where it would be running fine, even idling, and then the rpm would start dropping (with no drama) somewhat gradually. If I caught it, with a few extra pumps of the accel pedal, it'd come back and act fine.

It also did that while driving down the freeway. Pumping the accel didn't help those times, though, as it just stopped running as I aimed it toward the shoulder or off ramp. It was hard to get it to restart and stay running, but it eventually would. Sometimes, it would run at idle and sometimes it took fast idle to keep it running long enough to get it back into "D" and hopefully drive off (usually making sure the right rear wheel was on the dirt to lessen driveline shock when I put it into gear). When I got industrious (after getting it back to my storage shop), I put a new fuel pump on it and it started and ran better than it ever had.

There might be some issues with the carb's fuel circuits being clogged internally, but getting a good fuel supply would need to happen first.

Just some thoughts,

NTX5467

[Guest low'n slow]

When you changed the filter, did you also change the filter in the carb? There is a little check valve inside the paper filter that can cause this same problem.

[Guest sledhead]

ran into same problem with my 1956 found the problem is the new gas (Vapor locking) put NAPA elctric pump a long frame with switch under dash when car is ready to stall i turn it on works great. There is a articale in Old Car News August issue that has a different fix Put tee in fuel line after the pump plug center outlet drill .040 hole run return fuel back to fuel fill tube. Put fitting in fill tube. Chrysler and others have has the same problem. It's a guess!!!