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Tips
Tips

distributor diaphragm

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19_again

19_again

Jedi Warrior
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The vacuum advance on the new gt6 is not connected, the po told me that he suspected a hole in the diaphragm. Is the diaphragm that piece that's attached to the side of the distributor and is sort of bell shaped?
 
If you want to test it, you can start the car and let it warm up and come to normal idle speed. Then hook up a piece of vacuum hose to the advance port and either pull vacuum with a pump, or simply suck on the hose to see if the advance works. If it does, the idle will increase slightly.

If you, it could be frozen and not moving. Or there could be problem sinside the distributor.

If you want it done right and for your car to run a lot better, check this out and call Jeff at Advanced.

https://www.74tr6.com/distributor.htm
 
Actually, you don't even have to start the car. Just take off the distributor cap and suck on the hose. If the diaphragm is good you should see the plate move. Make sure it's moves freely first or you might turn blue trying to get it to work. You'll know right away if the diaphragm has a hole in it.
 
Or, don't even remove the cap. If you can continue to suck air from the hose, there is a leak somewhere, likely a hole in the diaphragm.

Some cars have a deliberate leak, but not Triumphs.

BTW, the diaphragm is inside that sorta bell shaped thing.

Also BTW, my local auto parts store was able to send my advance unit out for rebuilding, when new ones were not available. If you can't find a replacement, you might investigate that approach. Leaving it disconnected won't hurt anything, except for somewhat lower fuel mileage when cruising.
 
You might want to contact Jeff at Advanced Distributors. His contact info is on this link:

https://www.advanceddistributors.com/index.htm

Last year he told me that he was expanding his services to include starting an in-house vacuum advance rebuild service. Even if he is not there yet, he still offers rebuilt vacuum advance units for many applications.

Also you can check his company out in the "Vendor and Product Review" forum. I'm a happy customer of his.
 
Thanks all, I planned to send my MG dizzy in to Jeff for recurve last year after having the rocker arm rebuilt but was having too much fun driving. Now with the new addition of the GT6 and the B going into the body shop for new paint over the winter, I'm jumping to the mechanics on the gt. From all your advice, it will be a matter of minutes once I start to determine if there is or isn't a leak. No suspicion necessary.Thanks again.
Mike
 
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