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76 TA Vacuum / Thermac Lines

Seventy6er

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So after much distress elsewhere, I finally got to my 400 4bbl's sensitivities and realized that not only had some previous owner jacked up all the vacuum lines in every wrong way possible but also that I seem to have some mutant edition for which there is no correlating diagram, anywhere.

Anyways, so back to the beginning of time, I go and ultimately started from baby scratch and discovered what worked to get her purring again, and she runs like a champ now.

I thought I'd share my own diagrams in the event there is some other unfortunate soul who is in a similar dilemma in need of a possible solution (and I keep copies in the vehicle should she ever need to stay at a shop with a Wile E. Mechanic prone to spaghettified the system).

Enjoy.

Seventy6erVacuumLines.png
Seventy6erThermacLines.png
 
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Seventy6er

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What makes you say you have a mutant edition?
My Rochester (17056274) has two ports missing, the T and H.

Images from carb shops online show the same carb model with at least the H present, as well as my Haynes manual, with only one source without it, but that was eBay, yet they all identify the model as correct for the 76 TA with 400.

Even stranger is that while some online references suggest that the carb model "---56" is correct for the 400, the factory assembly manual identifies the part number as "---57."

So, I'm not sure what the discrepancy is.
 
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bhill86

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Gotcha. I thought I had a ‘76 service manual to compare, but I don’t have that one.

I’m not much more help.

This would be my go-to for info if you haven’t run across this site.

Cliff has the utmost knowledge of Qjets, which may assist you some.

If not, he could also probably provide some insight via phone.

 

Seventy6er

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That was a great resource; thanks, B.

With it, I've confirmed mine as correct in series, year, and manufacture, which gave me some further direction.

Somewhere down the road, I'll figure out the reason for the missing ports, which I may be too OCD-focused on at the moment for no reason, LOL.