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Posted By : Stephen Airey, 03-Apr-2004, 09:51am
In the Triumph service manual it says that you should check the correct operation of the vacuum advance by disconnecting the vacuum pipe with car at idle.
It says that if all is OK the revs will increase by around 500rpm. I tried this yesterday and noticed absolutely no difference to the revs whatsoever -
suggesting the vacuum advance unit is dead. However, the car runs fine so I am not sure. Are there any other ways to check the operation of the vacuum
advance unit? Is it a common problem for it to give up the ghost? It looks easy enough to change - but is it worth changing?
Any thoughts most welcome.
Cheers
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Posted By : Dom Weaver, 03-Apr-2004,
01:19pm
Hi,
To test the vacuum advance is working ok:
Take the distributor cap off and disconnect the vacuum pipe at the carb end.
If you suck through the pipe, you should see the advance mechanism moving in the distributor. If you get nothing, then the diaphragm in the vacuum unit
has perished or you have some sort of air leak.
New vacuum units aren't expensive and a second hand one will usually be fine. Don't know about Spits, but some GT6's have different connections on the
base plate so it's best to compare your original with the replacement before purchase!
Dom
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Posted By : Geoff Livesley, 20-May-2004,
10:01pm
Dom's advice proves that the diaphram works. You also need to check that a suck is getting to the diaphram. Disconnect the pipe from the
distributor while on fast idle and you should be able to detect a suck with a wet finger. I have a problem of loss of suck due to splits in those
rubber elbows (I talking Mk2 distributors). Does anyone know where to source them?
Hope you sort your problem
Geoff