Behind the Tachometer
Thread Starter
Drifting
Joined: Jul 2002
Posts: 1,254
Likes: 1
From: Edinburgh
Behind the Tachometer
I have a little cannister (actuator?) bolted to the rear of my tachometer in my 1970, it has a vacuum hose and electrical wires attched. Whats its function and what is it called?
Thanks
Graeme
Thanks
Graeme
Last edited by Graemeinvette; Mar 12, 2008 at 06:05 AM. Reason: Want to see replies
Safety Car
Joined: Feb 2006
Posts: 3,557
Likes: 0
From: Ridgeway VA
That solenoid is available from major cat houses - however, I've seen some priced at $80. (If this part is made in China cost is probably under $3.oo - but it is a hard to find part thus the price.) Do a search because some time ago - months - there was a thread on how to rebuild that piece.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
Doesn't it function? It is merely a 12v solenoid switch that has a valve for passing vacuum. Test it first to make sure there is something wrong with it before you throw $80 at a new Chinese part. Many times the solenoid just gets "cruddy" inside and won't pass the vacuum. It may just need a good cleaning.
Le Mans Master
Joined: Mar 2001
Posts: 6,640
Likes: 287
From: Ann Arbor Michigan
Doesn't it function? It is merely a 12v solenoid switch that has a valve for passing vacuum. Test it first to make sure there is something wrong with it before you throw $80 at a new Chinese part. Many times the solenoid just gets "cruddy" inside and won't pass the vacuum. It may just need a good cleaning.
Not very complicated. Put 12VDC to the coil and listen for the click. Use a hand vacuum pump (you have one right?) to check for leaks.
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Le Mans Master
Joined: Mar 2001
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From: Watkinsville, GA and Glen Cove, NY
A related question. I have one of these off of a car I parted out and the two terminals are broken off. If I take it apart is there a way to fix that. It seems they were just held by a very small "corner". Thanks for the help before I take it apart.
Bill
Bill
Thread Starter
Drifting
Joined: Jul 2002
Posts: 1,254
Likes: 1
From: Edinburgh
Thanks for all your help guys.
Graeme
Le Mans Master
Joined: Mar 2001
Posts: 6,640
Likes: 287
From: Ann Arbor Michigan
If the 2 terminals are broken off, it might be junk. The coil is connected to these two terminals which are molded into the coil bobbin. The 2 terminals need to be insulated from each other.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
The only feedback I would add is this.... The original part lasted well over 20 years before it malfunctioned; and it is probably only dirty. If you get it cleaned up, it will likely work well for another 20 years. A "modern" replacement will not be made to last nearly as long. So you can install a new one which may last 5 years; or you can clean up the old one [assuming there isn't any permanent damage when you check it out after cleaning], put it back in, and probably never hear from it again. Your choice.
