Vapor recovery system

Chatis · #1 (**permalink**) 04-23-2005, 08:03 PM

Looking for some wisdom.

As I progress with the rebuild of my car I have come to a point where the mods I make will impact the originality of the car.

I am not putting the Spica back in. I am putting in Webbers. Now, do I need the vapor tube that goes to the vapor recovery system or can I just duct it into the inlet manifold which is cleaner and neater. The early GT’s and Juniors did this but I am not sure if I am going to cause some sort of problem.

Also, since I am using Webbers do I need to take the line back to the condensation vessel in the trunk?

Lastly, any wisdom on putting in a more modern alternator?

**alfaparticle** · #2 (**permalink**) 04-23-2005, 09:29 PM

Are you asking about the engine breather hose that connects to the right side of the valve cover? If so, it can be connected to the air box on the atmosphere side of the carbs. I think that it should not be connected to the intake manifold. If in doubt, look at the Euro airbox.
Ed Prytherch, Columbia SC
74 GTV - Webers
79 Spider - Webers
88 Verde
73 GTV parts car - Webers

Chatis · #3 (**permalink**) 04-24-2005, 01:17 PM

This picture shows the hose I am talking about:

jpv · #4 (**permalink**) 04-24-2005, 01:44 PM

connect it to the air filter box. Thats the factory carburettor instalation.

Chatis · #5 (**permalink**) 04-24-2005, 06:52 PM

Thankyou much!

Blu Hollandese · #6 (**permalink**) 04-26-2005, 09:16 AM

Thats a very nice Super you got there JPV...although at little cleaning wouldn't harm it

**Andrew** · #7 (**permalink**) 04-26-2005, 09:49 AM

The big hose from the cam cover goes to the vapor separator, which feeds it back to the air box. The tiny hose runs the length of the car underneath, and goes to a vapor canister with a one-way valve in the trunk, behind the gas filler.

Andrew Watry

Chatis · #8 (**permalink**) 04-26-2005, 09:57 AM

So Andrew, If I vent the hose into the air box I can get rid of the vapor cannister in the trunk - right?

**Andrew** · #9 (**permalink**) 04-26-2005, 10:04 AM

It's not designed that way, but you could. The vapor canister in the trunk also is mainly a closed vent for the gas tank; it has several fittings, and I believe it works by vacuum at the front sucking the vapors from the canister up to the engine, where they get recirculated and combusted.

You'd need to re-vent the tank some other way (1969 US cars did it in the wheel well, without a vapor canister, which resulted in dirt and corrosion getting up into the system), or it will implode, and yes, the tiny vent at the front for the long hose to the vapor canister could vent to the air filter or vapor separator too. It looks externally like it comes from exactly the same point as the big vent for the vapor separator, but remove the two bolts and pull it out to see how the source is different. But if you don't have to worry about smog checks, or aren't concerned with increasing emissions, it should work fine, I'd think. But the gas tank must have some venting, or the fuel pump will cause it to collapse.

Andrew Watry

turbolarespider · #10 (**permalink**) 04-26-2005, 10:15 AM

I hate to rain on your parade, but hook the evap system up.

Since the basic system uses the PCV system that is already in place, it's hardly any harm to have it all installed, including the pipe that leads back to the trunk.

The benefits of using that system are quite large- vs. free venting the engine and gas, you eliminate roughly 70% of your car's raw HC emissions. That is a lot, especially since you live in California. And it's not like you are making the car drive worse or anything, just that you need to get the right tubing to connect the vapor tank to the PCV system.

Let me put it another way- the emissions that you'll clean up JUST by doing that is the equivalent of ~ 1000 new PZEV Focuses. I kid you not.

Eric

jpv · #11 (**permalink**) 04-26-2005, 02:36 PM

Quote:

Originally Posted by Blu Hollandese

Thats a very nice Super you got there JPV...although at little cleaning wouldn't harm it

Alex · #12 (**permalink**) 04-26-2005, 03:38 PM

Andrew,

Sounds good in theory but no vacuum that strong will ever build up in a gas tank. Sprint GTs have no venting at all and mine has yet to implode or collapse in the way you're suggesting. Just my two pennies worth, etc ....

**papajam** · #13 (**permalink**) 04-26-2005, 06:47 PM

The principles of the Euro carbed and the US injected crankcase venting systems are the same; routing crankcase gases back to the intake system to be burned. The difference is in the application; the US cars have an oil separator and the Euro cars do not. The separators only function is to separate out the oil vapor from the crankcase gases and send the liquid oil back to the sump. The Euro cars simply burn it all.
I'd try to leave the separator in place. Just run a large hose from the bottom of the separator to the Euro airbox. Ditto for the evap hose; leave it hooked up.

Alex,
Yes, 'tis true. Fuel tanks can collapse from too much vacuum. What typically happens first though is that the fuel pump can no longer pull fuel from the tank and the engine dies from lack of fuel.
Your fuel tank is vented, thru the gas cap. Note the holes at the arrows on this standard issue (pre-emission) Alfa gas cap. This is how a non-evap equipped car vents the tank. This cap BTW, 101.00.32.018.01, is listed in the parts book for your Sprint.

jpv · #14 (**permalink**) 04-27-2005, 11:19 AM

Quote:

Originally Posted by papajam

The principles of the Euro carbed and the US injected crankcase venting systems are the same; routing crankcase gases back to the intake system to be burned. The difference is in the application; the US cars have an oil separator and the Euro cars do not. The separators only function is to separate out the oil vapor from the crankcase gases and send the liquid oil back to the sump. The Euro cars simply burn it all.
I'd try to leave the separator in place. Just run a large hose from the bottom of the separator to the Euro airbox. Ditto for the evap hose; leave it hooked up.

turbolarespider · #15 (**permalink**) 04-27-2005, 11:33 AM

If I could suggest...

Instead of trying to find an oil separator for a US GTV or Spider, find one for a 164. They are a far better desing, primarily since they are plastic and not metal. The metal ones are notorious for rusting and plugging up.

So, feed PCV line to it, take oil drain back to dip stick tube- which you should be able use on the dipsitck tube.

The fuel vapor line should feed the raw PCV line, which will then feed into the intake.

If you replace the cap that Jim showed, you will have to install the one way valve that the later spider uses- I have one on my car- works like a charm.

I know that's not exactly clear, but it's something...

Eric