The Stovebolt Site Forums The Shop Area Engine Shop THE STINK!!!!!

I drive a 57 Chevy 210 Sedan with the 235. The engine has been overhauled and currently run the split manifold set up with one rochester carb. I have run an Edelbrock dual carb set up and also run the factory exhaust manifolds, but the stink has always been present. It smells strongly of exhaust and raw gas. The exhaust system doesn't have a leak in it nor does the carborator. I have put new weather stripping in it and even a new interior in my restoration process, but still the stink is there! When I close all of the windows it isn't bad, but when I try to get some ventilation it STINKS!! I can't find where it's coming from and it is frustrating me. I love driving the car, but hate smelling like a weed eater when I get out. Please help!!! What could it be? Could it be that these engines vent to outside air.... no this couldn't be because I have installed a PCV valve on the oil breather that goes to the air cleaner and I hooked a hose to the road pipe that vents past the passenger compartment.....

I'm stumped.... Please HELP

If you get sick of the problem I'll send you my address down here and you can send her to me.

Seriously have you looked at the boot (trunk). Check your seals and any other hole that may be present that the fumes can travel through and into the car via the back seat. Same with the floor. That would help explain why it isnt so bad when the windows are up - no flow through ventialation. Good luck.

Good thought, but the truck has a new seal around it... Does anyone else have this problem? I was thinking also it might be bad intake valves that were causing the fumes to come back through the carborator, but i'm getting around 140 psi out of all cylinders on a compression check.. Anymore ideas?

where does your exhaust pipe exit the underside of the vehicle? should go ALL the way to the rear and have a small bit of extension beyond the bumper - straight or down or toward the sides, but ALL the way - if pipe[s] end just B4 or after the wheels, unless aimed well out the side, you will wind up drawing some emissions into the interior - also bad for the rear suspension and frame

I can say from experience the tri5's are really hard to seal up, firewall and front area, due to the design of the "fresh air" system, and it's always tough to eliminate ALL leakage of fumes from intake and exhaust - I've had a 55, 2 56's and 57 sedans - all smelled like old trucks so I stick w/ old trucks, where ya don't notice the smell

Bill

find a smog machine wave it around

You should have a Positive Crankcase Ventilation system or a Road Draft Tube. You have neither. The "road pipe" you mentioned, is called a Road Draft Tube. The key word here is Draft. Air passing underneath the car passes the end of the draft tube and creates a low pressure or vacuum inside the tube. This pulls the fumes from the crankcase, and the fumes are replaced with fresh air entering through the breather in the valve cover.
With a PVC system, manifold vacuum pulls fumes from the crankcase through a pvc valve. The fumes are then burned along with the air/fuel mixture. Air enters the crankcase through a filtered valve cover cap or through a tube to the air cleaner. The carb air cleaner then is filtering the air entering the crankcase. There are other ways to set this up, but the idea that you have a closed system is the same.
If you check the links above, you will find some of the ventors supply a conversion for this.

Squeeze,
The exhaust pipes go all the way to the end of the car and exit about 1 inch past the rear bumper.

Richard,
Are you saying that when I put a hose on the end of the road draft tube, I defeated its purpose? Am I not doing the right thing here? Could the smell even come from the crank case, or is it the carb?

I also had a 69 Chevy pickup. It had holes in the fire wall, but didn't smell like that.

Maybe the carb is too rich.. How can you lean one out? A new jet? And what size jet is good for my setup?

Yes, altering the draft tube would render it inoperative. A "PCV valve on the oil breather that goes to the air cleaner", could very possibly prevent any air from entering the crankcase.

Yup. Pcv valve should be connected to manifold vacuum and if you're gonna run that, the road draft tube should be replaced with some sort of filtered breather for the crankcase...like maybe at the other end of the valve cover.

Fresh air should flow into the crankcase thru the breather, thru the crankcase and then into the intake manifold for combustion. This is one "smog device" that's pretty effective.

If you don't want to run the PCV, then you should have a breather cap on the valve cover for fresh air to enter and then the road draft tube open for vapors to escape...and have it open so that air passing by it creates a negative pressure, and as a result scavenges the vapors out.