What is this?!? Long distance trip tomorrow!

[disco_fever]

please help. I found this part sitting on the belts and pulleys in the engine bay, the tube seems to have been sliced through by the pulley and there was gouging. Luckily the belt looks fine. Tried to read the # on it, but it was illegible, it does say Lucas on the top. So what is this!?

the car runs fine and i browsed through the rave cd looking at diagrams... I am a little worried

thanks for the help guys.

 

[Sergei]

Vacuum advance unit from your distributor it is. I wouldnt try to drive without it..

 

[Louis Juarez]

Yup , vacuum advance for your distributor. There's two little screws that hold it on the outside of the distributor body, and a vacuum hose that connects the advance to the top of the plenum chamber....if it is not connected you will have a vacuum leak.

 

[disco_fever]

thanks guys, looking at the distributor i see how and were it attaches and the vacuum line, it seems the bolts just fell out. Long shot here, what kind of bolts/screws would work and is there a proper side up?

any Suggestions on what to do with it? what exactly is its purpose and consequences of running without it?
if i need a new one(mainly just need the screws), what would it run me?

A source I read says(basic google search) it helps with fuel economy, I have noticed a drop in fuel economy recently.

 

[Louis Juarez]

Chris , I believe that you only need the two screws. I don't know the size but I do know that they are small....like an #8/32 or #10/32 screw ( I am only using these sizes as a comparesion for approx size)...also these screws are very short so as not to protrude into the dist body . My workshop manusl shows the screws, but doesn't give the size.
I beleive that the screw that holds the electrical connector to the dist. body is the same size...I am not certain of this but I kinda recall that it is the same screw.

Check the dist. body to see if one of the screws still might be there. When you go to reinstall the advance, the little arm goes through a hole in the body and around the post on the plate where your pick-up coil is mounted to, replace the two screws and connect the vacuum line. You should be able to do this by only removing the dist. cap and not have to removethe clear dust cover under the cap.
If you do have to remove the dust cover you will have to remove the rotor....be very careful on this because I Went to change my rotor last tune-up, and the roter was stuck on the shaft. I pulled up on the rotor, which pulled up the shaft, which pulled the springs off of the centrifical advance weights.

 

[Steve83]

3.5mm x 0.60mm x ~9mm long. I have the leftovers of a rebuild kit (RTC5971) that includes them. I'll upload a higher-res version of this in the Diagrams album of my signature link.

 

[Louis Juarez]

Good move Steve

 

[p m]

Vacuum advance unit from your distributor it is. I wouldnt try to drive without it..

Sergei, not that much of a problem. It's just a little sluggish, that's all. Can set initial advance sooner, and live with it.

 

[Sergei]

Hmm.. Little sluggish?

My understanding was that it basically got this device as part of timing advancing, i.e adapting ignition timing to engine situation. Should it fail to advance - wouldnt it cause fuel to not burn completely/properly, thus moving it off to exhaust and get O2s flooded and screwed?

I am little bit nutty about ignition lately, i know..

 

[p m]

There's mechanical timing advance. Vacuum advance works off the ported vacuum - that is, proportional to airflow through the intake rather than engine speed. I bought my rangie with vacuum advance inop - but I could drive it okay in most situations.

 

[Sergei]

Thanks for info, Peter. Meditate on it i shall

 

[Electro Gremlin]

3.5mm x 0.60mm x ~9mm long. I have the leftovers of a rebuild kit (RTC5971) that includes them. I'll upload a higher-res version of this in the Diagrams album of my signature link.

All I know is that this odd-size 3.5mm screw is a pain in the butt to find -- I've had them fall off twice, so now will apply low strength Locktight to them and hope they hold. They are a pain in the butt to install, too. You need a 1/4" ratchet with a Phillips screw driver head to get the one on the right. Torx head screws would help if you can find them in this size.

Luckilly, I had extra screws from an Atlantic British kit that hold down the round plastic plate under the distributor cap -- they are the same size as the ones that hold the vacuum advance on. Also, if need be, you can use those hexagonal fittings that mount the above plate to the inside of the distributor.

If only they used 4mm screws, you could find them at any industrial bolt & screw shop.