D-jet troubleshooting, Only one item left on my list! Options

[914_teener]

Bob,
Some may remember my long thread after installing my 2.0 djet bucking at 3300 rpm.
After months and tons if money changing injectors ,tps ecu, vaccum lines trotle body and gasket, the issue was a $100 fix.

It was the vacuum advanced on the dizzy getting stuck. I replaced it and that was it.

I know it could be a number of things as stated in your thread, but you can do a simple test by sucking air out of the tubes and see if the arm moves.

Give it a try
Here is the thread Buckling at 3300

Yep.....and testing the vac at the can....it has been suggested a couple of times.

[zymurgist]

Wow, good info in the linked thread. Mine is doing this too. Distributor is fine, though, I just had it apart and lubed everything and made sure the advance plates and can were all in working order.

[luskesq]

Timing (and it wasn't off by much) caused my issue as well as a defective vacuum advance (wouldn't hold a vacuum for long).

Keith

[watsonrx13]

Well finally had a chance to check the vacuum advance on the distributor.

Here are the steps I took (photos to follow).

1. Removed distributor cap
2. Disconnected the vacuum hose
3. Hookup up a vacuum gauge (hand pump to bleed brakes) to vacuum advance on distributor
4. Pump up the vacuum and checked movement of arm.
5. No movement on arm
6. Hookup vacuum gauge on other line
7. Pump up vacuum and noticed movement on arm
8. Reconnected vacuum line to other side of vacuum advance (using a hose clamp)
9. Test drove car

Conclusion: the car didn't sputter, but now the idle is around 1600 RPM, before was 900 RPM.

So is this a good solution?
If this is a good solution I'll readjust the idle.

Vacuum pump hooked up to first vacuum line


Close up of connection of vacuum pump


Vacuum hose hookup to second vacuum line with extra hose clamp


Wide shot of distributor/vacuum hose connection


Vacuum pump set up


Vacuum pump kit

[r_towle]

The distributor has never been cleaned...well it's 40 years old and it may be time to relive the advance plates...

Cost is about 5 cents of grease and some time.

Rich

[type47]

I checked the vacuum advance on a distributor on a project motor and was surprised at how little the plate moved with vacuum applied. Anybody have an estimate/comment about the amt of movement?

[r_towle]

I checked the vacuum advance on a distributor on a project motor and was surprised at how little the plate moved with vacuum applied. Anybody have an estimate/comment about the amt of movement?

Depends upon the distributor.

Rich

[watsonrx13]

The distributor has never been cleaned...well it's 40 years old and it may be time to relive the advance plates...

Cost is about 5 cents of grease and some time.

Rich

Rich I think you missed my point. When I checked the second vacuum line on the vacuum advance, the arm DID move.
My question is: 'Is it OK to use either vacuum line on either side of the vacuum advance?'

--- Rob

[TheCabinetmaker]

One port is advance, the other is retard.

[boxsterfan]

I think your vacuum line (as pictured) is hooked up to the wrong port on the cannister for a 74 2.0L. Mine is hooked to the other port on the cannister. And the port you are hooked to is left open (mine has a short 3-4" piece of rubber hose on it connecting to nothing). Some cars had a connection on the plenum for that side of the cannister.

[r_towle]

Yup, one is advance, one is retard.
Retard was left up capped and floating in the atmosphere on stock cars.

Also I think some parts swapping was going on because in order for it to work properly, you would need a throttle body that has one vacuum port in front of and one port behind the throttle plate.

Not every car has the right throttle body and not every distributor has both ports for retard and advance.

Mixed results in the car I tuned that had everything required.
It would slam back to idle between shifts....

[watsonrx13]

Rich thanks for the reply, that explains everything.

--- Rob

[type47]

I checked the vacuum advance on a distributor on a project motor and was surprised at how little the plate moved with vacuum applied. Anybody have an estimate/comment about the amt of movement?

Depends upon the distributor.

Rich

039.xxx.??? but it's a 2L distributor...

[TheCabinetmaker]

Where does the hose with the clamp go to? It's headed the wrong direction. That hose is to too big also.

[914_teener]

I really think you should yank that dizzy out and make sure the the little ball for which the advance plate rides is clean and moving fully....if you haven't already.

My .02...just from the look of it.

[watsonrx13]

Thanks for everyone's suggestions. I have pulled the distributor and removed the vacuum advance. I visually checked the arm and it looks clean. I also manually was able to move it. I hooked up a vacuum gauge to the advance port and nothing moved nor did it hold vacuum. I hooked up to the retard port and was able to get vacuum and movement.

At this point I'm assuming the advance side isn't working and I've placed an ad for a2.0l vacuum advance.

Once I've replaced the vacuum advance I'll reinstall the distributor, hook up the vacuum hose and test the car again.

Also someone commented about the vacuum hose not routed correctly, I've included a photo of where the hose is connected to the plenum.

Stay tuned for more updates.

Vacuum advance, advance side where arm comes out.


Distributor (039 905 205A) with vacuum advance removed. The advance is removed by removing the circlip from the distributor and (2) screws.


Distributor removed. The distributor is easily removed by removing the wires to the FI trigger and coil and unbolting the mounting nut and washer. Do NOT loosen the locking arm.


Location of the vacuum advance hose on the plenum.


--- Rob

[r_towle]

Remove the other two screws and pull out the actual advance plates...the plates that your points are attached to.

Be careful not to break the ground strap between the two plates.

Pull them out, pull off the little clip on the side.
There is a single ball bearing in there that could fly across the floor....so go slow.

Open them up and see the sludge....
That is why they don't move well when it gets hot.

Clean and re grease that setup and out it back in place.

Your car will run fine without the vacuum advance. That is there to being on the advance a little earlier, but eventually the rotating for extends the advance plates anyways to full advance.

[watsonrx13]

Rich, which (2) screws are you talking about removing?



--- Rob

[watsonrx13]

OK, I reread your reply and did the following

1. Removed screw from condenser and removed from distributor
2. Removed (2) screws that held the clips
3. Carefully removed the actual advance plates
4. Removed clip with ball bearing

What should I use to clean the parts? Can I use some aerosol electronic cleaner I got from Radio Shack?

After cleaning, where should I put grease?

Before shot


After condenser removal


After (2) clip and advance plate removal


Dirty distributor


Clip with ball bearing removed



--- Rob

[Dtjaden]

Carb or brake cleaner would work well. The RS cleaner will most likely not be strong enough.

OK, I reread your reply and did the following

1. Removed screw from condenser and removed from distributor
2. Removed (2) screws that held the clips
3. Carefully removed the actual advance plates
4. Removed clip with ball bearing


What should I use to clean the parts? Can I use some aerosol electronic cleaner I got from Radio Shack?

After cleaning, where should I put grease?

Before shot


After condenser removal


After (2) clip and advance plate removal


Dirty distributor


Clip with ball bearing removed



--- Rob

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