Euro manifold nipple

[La Voce]

What is supposed to attach to this please? I discovered it as I was disassembling my Weber conversion engine (was a Spica car), and it was capped off, and I'm trying to figure out what is supposed to attach to it.
Thanks

[papajam]

The fitting has a hose that goes to the vacuum switch (that controls the ignition advance relay) and to the temp sensor on the air cleaner (that controls the blend door on the air intake).

[super1750]

On all European models with Bosch or Marreli centrifugal advance distributors that I have seen, that nipple is connected with a hose to a little nipple/fitting on the crank case vent on the valve cover (where the bigger hose goes to the air filter) and is generally plugged on one end to look original but not direct the crap from the vent directly into the carb. The nipple is also often just replaced with a small bolt and locktite.
regards
Bob

[super1750]

Here is a pic showing the hose mentioned in last post

Bob

[La Voce]

Thanks- so in the above photo, it's sucking crankcase fumes directly into the intake stream- probably at idle, then at higher rpms the majority of the fumes are pulled into the air filter box?

[papajam]

Yes, this is correct for many Euro version cars.

Keep in mind though that the Euro cars of this time period do not have an oil/vapor separator like your 79 Sprint. This is why the vacuum hose routing is different.
Is the separator and the vacuum switch still installed in your Sprint?

[La Voce]

No afraid not, when a PO converted the Spica to Webers he ran a hose from the cam cover with a filter at the end that dumped fumes in the engine bay (that were subsequently sucked into the cabin). By eliminating the filter and routing the hose to touch on the Weber's filter socks, I rigged a quick fix that works well above idle speeds but not at idle, and now that I'm rebuilding the engine I want to improve upon the solution. I've been toying with the idea of installing an experimental aircraft aftermarket oil/vapor separator. There’s a small nipple integrated into the dipstick post that I assume was meant to accept oil draining from a separator. I also may go ahead and run a hose from the manifold tap directly into the cam cover hose and replicate the setup in super1750’s picture. I’ve wondered what this is component is since I bought the car, as it has a nipple I’m assuming it’s a part of the original vacuum switch?

[super1750]

Hi Jim, or better Jims (both of you)

I have also wondered what that nipple and the hose to the crank case vent on European versions were actually good for and assumed that the hose to the vent was just a quick fix for a left over hose on cars delivered without a vacume advance distributor and actually doesn't have any real use or importance. Please correct me if I'm wrong on that. One definite downfall of that little hose is that you have to make sure that it is plugged when synchronizing the carbs or else you get corrupted vacume measurements. Another thing that I have seen on motors with that little hose still on and functional is the #1 spark plug gunking up quite badly when going down long hills (ie. in the mountains) to the point of having the #1 cylinder not fire any more. I, for my part, always leave the hose on but plug it and, as of yet, have not noticed any negative effects.

The easiest solution to that problem would probably be to install the original European filter set up. It is a good set up, directing cold air to the carbs, and can easily be made even better by drilling additional holes in the center tube. In addition, the Euro filter set up also filters the vapors before they reach the carbs. If you don't want the hot air and oil vapors going into the carbs and combustion chambers you could run the (large) hose into a little vented catch tank, as that is often done here in Europe. I will see if I have a picture of that sort of set up and post.

regards
Bob

Sorry, no pics.

[papajam]

Quote:

Originally Posted by La Voce I’ve wondered what this is component is since I bought the car, as it has a nipple I’m assuming it’s a part of the original vacuum switch?

[La Voce]

Yawsa, stock dual point distributor.

[Gordon Raymond]

BTW that little fitting has a 7 mm thread. If you plug it with anything, check to see if you have a 7 mm bolt around first! Finally found 2 in my "odd stuff" box the other night!