Evaporation control system

[PeterBiggerstaff]

Hi all,

I've started pulling my D's fuel system apart, and I'm glad people here told me to do that before I tried starting it! If you want to see the details check my blog as this is not what I'm asking about here:
http://delorean.co.nz/mydmc/?p=140

My question is, how critical is the evaporation control system? None of the hoses are connected to the carbon canister apart from the one line that goes back though the rollover valve and into the fuel filler.

The other 3 hoses have all been cut off and are just hanging out the side of the pontoon. Do I need to replace all the hoses as per the vacuum hose routing diagram, or was this just a subsystem that was installed for emissions compliance like the catalytic converters?

[DMCMW Dave]

Hi all,

I've started pulling my D's fuel system apart, and I'm glad people here told me to do that before I tried starting it! If you want to see the details check my blog as this is not what I'm asking about here:
http://delorean.co.nz/mydmc/?p=140

My question is, how critical is the evaporation control system? None of the hoses are connected to the carbon canister apart from the one line that goes back though the rollover valve and into the fuel filler.

The other 3 hoses have all been cut off and are just hanging out the side of the pontoon. Do I need to replace all the hoses as per the vacuum hose routing diagram, or was this just a subsystem that was installed for emissions compliance like the catalytic converters?

It's an emission control system. You can't just cap off everything as that would seal the system and cause pressure to build up. The hose(s) that comes from the front of the car needs to be open to something to let the tank breath. The other hoses are the purge line to the engine, and the purge control that opens the vent when the engine is running to burn off the fumes that are stored in the carbon can. Assuming you don't mind disabling the system and the associated legalities (may not be issue in New Zealand, but if you are subject to a mechanical MOT type inspection they may look for it) you can cap off the two engine hoses and leave the tank line open. Somewhere away from the engine or somewhere that the fumes would get into the car.

It sounds to me like that's what has already been done. There is no reason to disconnect all this, it has zero impact on engine performance.

[David T]

Hi all,

I've started pulling my D's fuel system apart, and I'm glad people here told me to do that before I tried starting it! If you want to see the details check my blog as this is not what I'm asking about here:
http://delorean.co.nz/mydmc/?p=140

My question is, how critical is the evaporation control system? None of the hoses are connected to the carbon canister apart from the one line that goes back though the rollover valve and into the fuel filler.

The other 3 hoses have all been cut off and are just hanging out the side of the pontoon. Do I need to replace all the hoses as per the vacuum hose routing diagram, or was this just a subsystem that was installed for emissions compliance like the catalytic converters?

The system is not critical and will not affect performance as long as you plug all of the vacuum ports. Besides emitting more fuel vapor you may smell fuel around the vehicle especially on a hot day. Since it won't take much or cost much to put it back together (assuming you still have the cannister in the left, rear pontoon) I would hook it back up.

[Nicholas R]

I repurposed the space in the pontoon that originally housed the carbon canister during my swap. The line that went from the the tank to the canister I kept, and routed to a pressure relief valve in the bumper that is designed specifically for fuel tank vapor relief. No negative effects as far as I can tell. Not sure a 30 year old carbon canister was really filtering as well as it once was anyway.

[PeterBiggerstaff]

Thanks for the feedback everyone, I might just leave it as-is until I get the car running, then replace all the vacuum hosing before I get the car compliance tested.