Will this vacuum switch work?

[GoHaunter]

So i bought a vacuum switch for my 78 280z and they sent me a 3 ported vacuum valve rather than a 2, do you guys this will actually be able to work?

Picture:

https://imgur.com/BtyrU3F

Thanks for any information!

[Lockleaf]

If you know which port does what, then there is no problem capping the the port you don't need.

[GoHaunter]

Yea that's what I was thinking of just capping off the middle piece but I'm worried that the thread my be different since there is only 4 on this one but on the actual switch it's 8 threaded. Do you think that could be a problem?

[datzenmike]

I would try for the correct one. I don't even know where your two port valve was used. Was it screwed into the engine coolant at the thermostat?

 

The 720 uses a similar one to your picture. The top port connects to the air filter, for clean air. The other two are for EGR and vacuum advance and are open or connected to the top one. Basically it's a vacuum leak that removes the vacuum advance and the EGR signal and deactivates them when the engine is cold. As the engine warms the wax pellet inside blocks one and then the other sealing the vacuum leak. At what ever the melting point is for the wax, this is when vacuum advance and EGR are allowed.

 

Now some L28s did not have EGR so this may just be for distributor advance, I don't know. What I do know is this is the wrong one for what you have.

[GoHaunter]

Hi sorry for the super late response and thanks for the info! The ported vacuum valve/switch thats on my car right now is this one: http://imgur.com/eW28LbV

I was wondering is the pvs suppose to be loose like that or tighten all the way?