Truck dies when I put it in reverse

[Busster]

Hey,
Im new to the forum, this has possibly asked before.... bear with me.

I just aquired a 72 with the original 350 and auto trans. There is some rust in the fuel, but I got it running rough but running. I can shift into drive and go forward, but everytime I put her in reverse she dies very quickly. Im thinking tourqe converter, what do you all think??

Any info is apprieciated!!
Thank You!

[NoNeck]

First of all WELCOME TO THE BEST TRUCK FORUM ON THE INTERNET!

There is some rust in the fuel, but I got it running rough but running.

If you have noticed rust in the fuel, more than likely there is rust in the carb. That's where I would look first. Contaminants in the fuel bowl will normally settle in the back of the fuel bowls. When you put the truck in reverse, the rust is probably sloshing against small inlet ports in the carb. The inlets get blocked, cutting fuel off to the engine. I would recommend a carb rebuild/cleaning using compressed air on the metering plates and carb body. You didn't say what kind of carb you have.

After the carb is rebuilt, I would thoroughly clean that gas tank before I reinstalled it. If you don't, you will just have to rebuild all over again.

There are dozens of excellent threads on cleaning the fuel tank on here. Just use the "Search This Thread" feature for all the info you would need to do it right.

I have never heard of a torque converter stalling the engine in reverse... but then I'm not Mr. Goodwrench either.

Good luck!

NoNeck

[LockDoc]

-
My '39 Ford Coupe does the same exact thing. It is a rebuilt TH350 won at a car show. I don't know about your truck, but after the '39 warms up good it doesn't do it again until you let it sit long enough to cool down. If you don't hold the brake pedal down you will go backwards about 20 MPH. I have asked every transmission guy I know or meet and none of them have had a definite answer for it. All have said they would have to tear it down and check it out.

When I first start mine and have to back up I shift it into reverse and as soon as it starts moving I shift it into neutral and let it roll backwards far enough to be able to drive forward.

If you find out what the problem is post back here or PM me if you would...

Thanks.
LockDoc

[Busster]

It has the 4 barrel quadrajet on it.
I am going to clean out the tank this week and hopefully it will keep running and shift into reverse. I will read those threads on tank cleaning thanks NoNeck!

LockDoc I will let you know when I find out what it is.

[LockDoc]

Originally Posted by Busster

It has the 4 barrel quadrajet on it.
I am going to clean out the tank this week and hopefully it will keep running and shift into reverse. I will read those threads on tank cleaning thanks NoNeck!

LockDoc I will let you know when I find out what it is.

Thanks. I find it hard to believe it will have anything to do with the carb or fuel system. I put a new BG Demon carb on mine for a different reason but that didn't change anything. I suppose it could have something to do with vacuum but why just reverse?.

LockDoc

[Square_78]

my truck does that in the cold before its warmed up.

[mrein3]

Originally Posted by Busster

Hey,
Im new to the forum, this has possibly asked before.... bear with me.

I just aquired a 72 with the original 350 and auto trans. There is some rust in the fuel, but I got it running rough but running. I can shift into drive and go forward, but everytime I put her in reverse she dies very quickly. Im thinking tourqe converter, what do you all think??

Any info is apprieciated!!
Thank You!

Way back in the day, I had a 1971 Monte Carlo that was original right down to the Transmission Spark Control (TSC) system. When everything in the TSC is working, it is supposed to not allow vacuum advance until the engine warms up a bit. Early emissions stuff. My monte developed a condition where it would run fine when cold until I threw the th350 in reverse then it would simply die.

I was working at a small time garage at the time so I told the head mechanic about it. He had me pull it in his bay where I stayed in the car and showed him how reverse would kill it. He pulls the air cleaner, did something and the problem went away. I asked what he did and he said he simply "disconnected this emissions crap". If I remember correctly there was a vacuum switch mounted on the carb. That must have developed a leak that when removed and plugged fixed the problem.

I hope this helps.

That stuff was long gone on my truck when I got it. When I put an Edelbrock 1406 on it I used that TSC wire's +12V to run my electric choke.