the209bnr

Help, my car has fallen victim of the fuel boiling over issue commonly associated with the 1982-1984 Trans Ams. It's sometimes a pain in the you know what to start once it gets really hot and I've had to have the "grim reaper" tow it home twice because it won't start if I have less than 1/2 a tank and the fuel boils over (Its so bad sometimes you can hear it boiling over in the tank). Plus the poor performance and sudden bogging/crapping out while trying to accelerate almost got me killed the other day when it died in traffic.

I've seen the fans that were added to help with the issue but haven't been able to find one.


I am looking for a solution that works, and I would greatly appreciate it if anyone has info on how to resolve it.

Thank.

sofakingdom

iTrader: (1)

https://www.cantonracingproducts.com...&category=8510

the209bnr

Thank You, I will try this

8t2 z-chev

i think by '84 model year,L69s had low pressure electric pump in the tank
to assist the engine mounted pump to reduce chance of vapor lock with
L69s-If your car has that pump,it might not be working or the foam
rubber coupler hose between the boost pump and the steel line inside
the tank has turned to goo and fallen off-this would also cause the
engine mounted pump to "suck air"once fuel level in the tank got below
the level of the failed coupler hose.
A 12/83 build L69 z28 i looked at had the boost pump as factory installed
but no carb blower.A 2/84 build L69 i saw had the boost pump factory
installed and had been retrofitted with a carb blower(blower was dated
1985)

the209bnr

Can you give me more info about that hose inside the tank? I just had the mechanical fuel pump go out two nights ago and just put a fresh one on it. Ran a little better but still feels off..

sofakingdom

iTrader: (1)

The standard setup, without the electric pump, doesn't have the rubber piece.

If you don't have an electric fuel pump, then the fuel boiling problem is caused by the fuel getting hot. (duh)

The fix therefore is, find where heat is getting into the fuel, and keep it from happening. (duh)

The place where heat and fuel come closest together, is the fuel pump. It's mounted to the block. The block is hot. Voilà, hot fuel. The cure therefore is, insulate the pump from the block. Even something as simple as putting in 2 block-off plate gaskets and 2 fuel pump gaskets will make a NOTICEABLE difference. In fact you could try just that, and see if it makes a difference; if it does, then you know you just found your problem, and the phenolic thing will almost certainly cure it completely.

People often get the idea that they can just use RTV on the pump, since there's no pressure there or anything, and that it will seal. They're right about that... putting a piece of paper in there doesn't keep the oil inside any better. But using no gasket allows MAXIMUM heat flow from the block to the pump, thereby raising the problem to a crtical level. If you have NO GASKET AT ALL in there, that's the very first thing to do, is put them back in.

The factory's "blower" thing was not particularly effective. I wouldn't bother. Didn't ever myself in fact, in all the years I've had my L69 car.

the209bnr

Thanks for the insight. Since you've owned one of these L69's can you provide me with any other info about them? (with minor issues i should look out for / solutions)..

dfscycle

Hello ~~~ I own a 1984 Pontiac Trans Am with a 305 H.O. engine and I have been dealing with a Vapor lock problem also, I have had it in the shop sevseal times and they have replaced the manual fuel pump ( No electric one in the tank ) removed the metal fuel line and rerouted a rubber linew, and I still have the same problem.
Also my electric fan comes on when the vehical starts and shuts off when I turn off the ignition is this supposed to happen.

Thannks in advance ~~~~~~~ Don

sofakingdom

iTrader: (1)

No, the electric fan is supposed to come on only when the motor reaches about 235°, and of course whenever the AC is on.

If you have the same problem discussed above (fuel boiling in the carb and spewing mercilessly everywhere, especially when trying to restart the car when hot) then the solution posted above is for you. $12 and about 15 minutes. You might be amazed, in fact you will be if you have that specific issue going on.

Most people who think they have "vapor lock" (a) don't know what that even is to begin with, and (b) have some problem completely other than that.

There's nothing wrong with the factory fuel line routing, or with metal line. In fact rubber line is more likely to cause SERIOUS issues (car catching fire and burning to the ground) than it is to fix ANYTHING. I'd suggest putting the car back like it came and identifying the REAL problem.

What does your car ACTUALLY do that you're trying to remedy? Leave "vapor lock" out of your vocabulary altogether and just describe in as much detail the ACTUAL behavior in as much detail as possible. "I start the car and x happens", "I push the gas pedal and y happens", "when the car is hot z happens", etc.

fteufert

The fuel line on my 1982 TransAm. It almost sits on the header. This is where the factory installed it. I never saw it until I pulled out the A/C parts under my hood.

I moved it up a few inches, and my starting issues when hot disappeared.