I've been getting some gas odor from my '71 Cutlass after I shut it off. I decided to remove/replace the charcoal canister. I admit I never paid much attention to this - and I see from the service manual that the "To Tank" outlet should be routed to the fuel vapor stand-pipe behind the rear seat. My outlet was just routed down to exhaust the vapor under the car.
Is this ok?
Is there any advantage or reason to route it back to the stand pipe?

And speaking of the stand pipe... it's always struck me as a bit odd that the fuel vapor system is located behind the seat - essentially in the passenger compartment! I guess this was ok in 1971, but is it truly safe? Are there any concerns with after-market fuel pumps/carbs that may be pushing slightly higher than factory fuel pressure??
Thanks!

 

There is a lot to learn in the details of how this system works. Perhaps someone could link you the correct routing, but I encourage you to do it factory correct. That stand pipe is probably safer than you think it is. Factory manuals are really great to have in this case.

There are several small hoses about 3-4'' in length, in parts of this system in the rear of the car. These hoses should be inspected and replaced. You don't have to drop the tank for these, and you'll find them at the corners of the gas tank near the rear end area. There are a number of components in this system but its pretty straight forward in operation.

About running higher fuel pressures...If you run too much pressure the carb will flood and thus not work. That is a another concern all together. That is why they make regulators.You can't run past 7lbs, the float can't hold it. And maybe not even that much before you'll have carb issues.

 

Mine is a '70, and the canister and all the hoses had been removed - and the garage smelled like gas. I took the time to get it back to the way it was from the factory https://classicoldsmobile.com/forums...utlass-131869/ and since I finished the project, the gas odor is gone. There are quite a few threads on the system if you search "standpipe". I'm happy I put mine back together.

 

tmbrennan:
I have attached a page from the assembly manual that shows the connections between the standpipe and the gas tank. I hope this helps!

Rodney