Thermoquad Rebuild and Throttle Linkage Setup

[mgm1986]

Starting to dig into the fuel system on my '68 300. The 440 has an Edelbrock Performer intake and a Carter Thermoquad 6518s from a "Chrysler Industrial" application, guessing an RV. Once she is running she starts and idles okay but the Carb is definitely in need of a rebuild as every moving piece is "Sticky", even after cleaning with aerosol carb cleaner.

Two questions. First, should I plug the inlet on the passenger side of the Carb when putting everything back together? Picture three shows with an arrow what I am referencing.

Second, the throttle linkage looks suspicious. Should there be a spring running from the throttle back towards the linkage near the firewall? Any pictures of what the linkage setup should look like? It seems to shift okay so I think it may be adjusted properly but it looks funny for some reason and I think something is missing or backwards.

As always, thanks for your input!

 

[Big_John]

First, should I plug the inlet on the passenger side of the Carb when putting everything back together? Picture three shows with an arrow what I am referencing.

That's the bowl vent. That needs to be open.

Regarding the linkage, yep, that spring doesn't look right.

It should look something like this where it pulls the trans throttle linkage (often wrongly called kickdown) against the stud. That spring you have looks too heavy also.

 

[mgm1986]

Thank you, @Big_John. That picture is exactly what I needed. I will have to measure to make sure I get the right spring.

 

[70bigblockdodge]

No plug that hanging off the passenger side it is the vent to the vapor canister, will leak gasoline on a very hard left.
The vents for the float bowls are the 3 tubes sticking straight up into the air cleaner, they will not leak fuel unless your floats are stuck down and or your upside-down.
Bend that spring anchor to make it more in line and flip the other spring to bellcrank pivot at the rear. May need a different spring.

 

[Big_John]

No plug that hanging off the passenger side it is the vent to the vapor canister, will leak gasoline on a very hard left.

Geez... I never thought about that. It's kind of a "duh" moment for me. Too obvious.

 

[70bigblockdodge]

Geez... I never thought about that. It's kind of a "duh" moment for me. Too obvious.

To be honest you would have to really be generating some pretty good G's to get the gas to spill out and if you hit the throttle the linkage (Y shaped thingy) near it shuts off the opening.
I'm pretty familiar with TQs I have 2 of them on the road and running beautiful.

 

[mgm1986]

So no plug = no track days? Otherwise plug it up?

 

[Big_John]

So no plug = no track days? Otherwise plug it up?

I'm deferring to @70bigblockdodge 's wisdom on Thermoquads and say to plug it.

If my TQ '70 wasn't up for the winter, I'd plug mine and try it.

 

[70bigblockdodge]

So no plug = no track days? Otherwise plug it up?

It only vents at idle to the vapor canister. The linkage right by it controls a cap that closes it off at pretty much anything over idle.
You have to really be flying in a left turn to get it to splash out, but better safe than sorry, and its basically pointed right at exhaust manifold or header. The 3 other vents are more than adequate.
If you have any problems with yours beyond a simple rebuild I would suggest sending it to Dave at Woodruff's carburetor
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@Dana
He will make your TQ more perfect. He did mine.
Ran flawless through all the traffic and heat on Power Tour and on the other car I picked up a tenth and a half in the quarter.