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#1 |
Member
Join Date: Jan 2011
Location: Stuart, Florida
Posts: 459
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What's this?
I know this is on a Pontiac (please don't rip me) but my 70 chev. p/up also had one. A guy on the Pontiac Forum wants to know and no one has figured it out. I thought it went to the air cleaner, regulating the fresh air flow from outside to hot air by exhaust, but i was never 100% sure . Thanks!
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#2 |
Registered User
Join Date: Apr 2010
Location: McFarland CA
Posts: 1,392
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Re: What's this?
Appears to be a TH400 kickdown switch
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Pancho 69 c/10 step side 454/400 with 3.07 |
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#4 |
Jamie Hyneman is my twin
![]() Join Date: Nov 2005
Location: La Junta, Colorado
Posts: 705
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Re: What's this?
It may be part of the anti-dieseling solenoid. I believe that 72 trucks had a vacuum pod like this that was connected to the carb and distributor. Power ran from the trans. to the vacuum pod then to the carb solenoid. 72 solenoid had one electrical connection.
71 had a similar setup, but it combined the vacuum on the back of the solenoid. 71 solenoid has two vacuum ports, and two electrical connections.
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Justin SOLD 1967 K10 Fleetside, 283, Front and Rear Posi SOLD Color Wiring Diagrams Now in High Resolution V8 and Cab and Cab and Chassis |
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#5 |
Registered User
Join Date: Aug 2009
Location: Bowser
Posts: 13,626
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Re: What's this?
IIRC it's a tvs. Transmission vacuum solenoid. Had one on my chevelle. One wire is powered. The other goes down to a switch on the transmission on a 4 speed tranny.
When you finally shift to 4th the switch on the tranny provides a ground. The vacuum switch opens and allows vacuum to the vacuum advance on your distributor. Lots of high compression motors ran like that. Very aggressive timing curve in the distributor but vacuum advance only under cruise conditions. |
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#6 | |
member #16
![]() Join Date: Dec 1999
Location: Yuba City Ca.
Posts: 3,618
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Re: What's this?
Quote:
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john http://67-72chevytrucks.com/vboard/showgroups.php board vendors ![]() http://www.flickr.com/photos/1745471...7602865984234/ |
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#7 | |
Member
Join Date: Jan 2011
Location: Stuart, Florida
Posts: 459
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Re: What's this?
Quote:
Posted via Mobile Device |
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#8 |
Jamie Hyneman is my twin
![]() Join Date: Nov 2005
Location: La Junta, Colorado
Posts: 705
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Re: What's this?
TCS solenoid is what I was talking about too.
__________________
Justin SOLD 1967 K10 Fleetside, 283, Front and Rear Posi SOLD Color Wiring Diagrams Now in High Resolution V8 and Cab and Cab and Chassis |
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#9 |
Senior Member
![]() Join Date: Jun 2005
Location: Winona Lake, IN
Posts: 6,284
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Re: What's this?
My 70 had the TCS system on it, but I don't recall a vacuum line, only a wire that ran from the solenoid to a relay box one the firewall and then down to a switch on the side cover of the trans.
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70 C/10 SWB 402/TH400/3.73 "The Needy Beast" 200,000 Mile Club Disc Brake Club Owner installed options: Front Sway Bar Power Steering Power Brakes Cigar Lighter Courtesy Lights Deluxe Side Markers Wiper Delay Power windows Power Locks Sniper EFI 2015 Silverado 1500 LS 4.3/6L80/3.23 lowered 2" front & rear |
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#10 |
Registered User
Join Date: Aug 2009
Location: Bowser
Posts: 13,626
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Re: What's this?
That was probably the kickdown for your tranny if you had a T400 in it. Different beast!!! LOL!!!
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#11 |
Senior Member
![]() Join Date: Jun 2005
Location: Winona Lake, IN
Posts: 6,284
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Re: What's this?
Nope, it was a 3 on the tree. It was definitely TCS, because I thought the switch on the trans was for the backup lights, and when I traced the wire and found what it was connected to, I looked it up and found out what it really was for.
__________________
70 C/10 SWB 402/TH400/3.73 "The Needy Beast" 200,000 Mile Club Disc Brake Club Owner installed options: Front Sway Bar Power Steering Power Brakes Cigar Lighter Courtesy Lights Deluxe Side Markers Wiper Delay Power windows Power Locks Sniper EFI 2015 Silverado 1500 LS 4.3/6L80/3.23 lowered 2" front & rear |
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#12 |
its all about the +6 inches
Join Date: Jan 2001
Location: Hilliard Ohio
Posts: 2,693
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Re: What's this?
That is part of the TCS system. It was plumbed in line with the vac line feeding the distributor. It would shut off the vacume unless the tranny was in top gear and regular engine temp was reached.
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