Who sells a vacuum advance dashpot for a '72 240z?

[timhypo]

So, I've been messing with tuneup-type stuff on my '72 240z after receiving my 240Z tuneup guide from Z Therapy and awaiting payday so I can buy a wheel cylinder and figured out today that my vacuum advance module is frozen solid. No matter how hard I suck on the hose going into the dashpot, the advance arm doesn't move. I've checked the usual suspects (roackauto, msa, black dragon) and don't see anyone selling one for a '72. While I realize this should probably prompt me to hit the junkyard and upgrade to the ZX model as is my longer-term plans for this car, I might be inclined to just buy one if they're reasonably enough priced. So, who sells one?

[Bruce Palmer]

Before you do that take the end of the arm loose from the advance plate inside the distributor housing and doing the sucking thing, see if it moves. If it moves, it's okay and your problem is more than likely in the advance plate in the distributor. There are three ball bearings held in place by a retainer that that allows the top plate to rotate on the bottom plate doing the advance deal the vaccuum diaphram controls. We see many aged distributors where the little ball retainers have come apart allowing the balls to escape often time wedging between the two plates showing up as an advance that doesn't.........

[oldhemi]

Good info, Bruce. If one does find his dizzy has your described problem, is there a source for the parts?

[timhypo]

Thanks for the info. I've been thinking about it and I think I'm gonna hit the junkyard this weekend and see if I can get a ZX dizzy/ignition module, alternator/regulator, voltmeter, tach, and locate a 3.90 R200 and a 5-speed. I might even pull the motor itself. There's no replacement for displacement!

[Bruce Palmer]

Good info, Bruce. If one does find his dizzy has your described problem, is there a source for the parts?

Yep, www.philbingroup.com 503-287-1718 in Portland. Ask for Mark. They can also do "done" distributors for under $150 bushed, recurved (in the case of the electronics) with new advance plates and everything ready to plug and play.....

[oldhemi]

Thanks Bruce!

[pbarcher]

I had the same problem with the vacuum advance on my '73 240Z. Since my engine is stock (except for the Pertronix and coil) I decided to have the original distributor built by Advanced Distributors in MN. They specialize in rebuilding and recurving distributors on collector vehicles, and I was very pleased with their work. The case was polished inside and out, and my car runs much better at low rpm.

The cost was about $95, but the work took about three weeks. Highly recommended.

[timhypo]

So, I took the two screws out that connect the advance module to the distributor body and when I pull the module away, the inside of the distributor swivels easily. I didn't disconnect the arm, but I think that this confirms that the issue is indeed the module itself, not the distributor. Would you guys agree? If so, is there a way I can free this thing up? I've searched and searched, but can't find anywhere on the internet that shows how this thing works...

[timhypo]

Ok, got another dizzy on ebay for 99cents plus shipping and, although it's supposedly good per the seller, the advance doesn't work on it either. I pulled it apart thinking I'd try to clean it up and fix it, but am having an issue. When I take apart the advance module and remove the spring, I can make the rod that the spring attaches to retract by sucking in as well as push back out by blowing, but with the spring attached, I cannot. The condition of the baseplate ball bearings is going to be irrelevant if I can't make this thing work. Is it possible that there's too tight a spring on this or am I just not sucking hard enough? I suppose I could borrow my buddy's vacuum dealie (it's got a gauge and a pump) to see how many PSI are required to pull it in, but it shouldn't be that much if it just uses engine vacuum...