Vacuum system help

Hi guys/girls

Got the dizzy completely rebuilt. But not sure if the vacuum pipes are the correct way round. Does any know or have a diagram of where the pipes go.

I have one pipe going from the plenum chamber (left hand side as you look at it from the rad end) this goes to the front of the dizzy vacuum unit.

the is a second pipe coming from the fuel rail area on the back of the plenum chamber area. (between the plenum and bulk head.) This goes to the back of the dizzy vauum unit.

A third pipe comes out of the top on the throttle area. This goes down to a ball in the front of the vehicle (where the second battery case is.) Below the power steering resevoir.
this goes through the bulk into the vehicle behind the washer bottle.

There is no cruise control fitted to this Car.

Any help would be grately appreciated

Which year do you have?

My 1990 3.9 only has one pipe from the dizzy.

How much did your dizzy cost to rebuild?

John

I have an 89 3.9 The first of the 90 models.

And I didn't need any parts for the dizzy so only cost me time and cleaner

I did ask the experts on here if it should have a pipe both sides of the diagraphm when I first got it , (I have only had it about 3 months) but they said not. only a pipe to advance I believe is what they said.

The diagraphm seems to be shot on mine and there is a bit of play in the shaft so I shall replace it.

The set up to the ball then to the pipe through to the bulkhead seems to be the same as yours though.

Have you looked in the haynes manual?

Yep. The Haynes Manual doesn't actually say anything about the damn thing. the only refernce to the vacuum system is the vac unit on the dizzy. or the vac pipes on the plenum chamber and throttle body.
Does you vac pipe go from the dizzy vac unit to the left of the plenum chamber as looked at from the front of the motor?

hang on ill go and get the torch and have a look!

ok , the one fron the dizzy goes to the throttle body and the one from the left of the plenum goes to the plastic sphere, on mine its on the engine side of the sphere and the one from the wing side goes off up the bulkhead some where.

Doesnt mean its right as mine aint exactly concourse!

Thanks for looking Fett. I have changed the pipes round to the same as your description. Let's see how that works.

Question for ya.

I just bought a secondhand one from ebay, how do you fit it, I am ok with spanners but is there any setting up or timing to be done?

Thanks

John

The vacuum unit or the dizzy?
If its the vacuum unit, there are 2 small screws/allan bolts holding the unit to the dizzy. Remove the dizzy and rotor arm. Remove the spark shield.
gently pull vacuum unit out of dizzy.when loose you will need to push the arm off of the advance retard thingy.
Vauum unit will come off now.
Reverse to fit
You may find it easier to remove the dizzy from the block though as there isn't much room in there. Mark the dizzy housing and somewhere on the engine so you can get the timing right afterwards. Remove nut securing the dizzy. This is located underneath the right hand side of the dizzy. (below the plastic amp) it's a 4/16 on my truck. I foun it easier to remoce the Alternator bracket.

Remove vacuum pipe and electrical connector. Pull dizzy out. ( try not the turn dizzt when out of engine. (I marked the position of rotor arm on the body of dizzy just to be on the safe side.
When re fitting, align the rotor to correct position and insert dizzy into hole. It should slide in smoothly and sit all the way in. If not apply gentle pressure. If that does work, pull dizzy out slightly and rotate a fraction then try again.

Oh, and the truck runs a lot better now. thanks for the info on vacuum pipes.
Now just need a new vacuum unit and tune up.

Mark the dizzy housing and somewhere on the engine so you can get the timing right afterwards.

The thing is that it will be a new used dizzy so the timing should be different? otherwise they would all be preset and un adjustable.

I have seen the vacume unit on ebay for about £40 new, which would be good for you.

I have too much play in my shaft to make it worth fixing.

is the play about 1/2 - 3/4inch?

If you turn it. Or side to side movement

Side to side movement about a 1/4 probably , may be more.

But any is bad. Also if you have it off the car and turn it its not a very good representation as it returns to where it normally wears when running at 2000 rpm as soon as you put it back in, that means more play normally.

I suppose I will have to get a new cap and rotor too as the old ones will be worn as theres so much play. pity , they have only been on about 1k miles