Ford FE 390 question???

[Matt34]

If you are facing the car under the hood on the left side there is a metal tube, at least on mine, that screws on to the carb and goes down to the intake manifold and looks like it use to connect to it somehow though now its just hangs there and has since I got the car...


I found out that line is a vacuum line...I think. My question is what does it do and is it necessary or better to have it hooked up?

[martyo]

A picture is worth a billion words!

[chief455]

A picture is worth a billion words!

+50
I only recall the vacuum advance line running the route you describe

[yjmud]

Passenger side would be the choke stove

[Zack]

Passenger side would be the choke stove

That reminded me of the stupid heat risers installed on many old cars.
Quite possibly the dumbest idea ever put into production.

[chief455]

That reminded me of the stupid heat risers installed on many old cars.
Quite possibly the dumbest idea ever put into production.

EGR

[Zack]

EGR

No sir. It was to heat the engine up quickly.

Problem was, when they broke.
Exhaust from one bank could not exit properly, which led to pinging and burnt valves (in extreme cases)

[chief455]

No sir. It was to heat the engine up quickly.

Problem was, when they broke.
Exhaust from one bank could not exit properly, which led to pinging and burnt valves (in extreme cases)

Point taken, but I still hate EGR. Choke stoves too!

[Fastbob]

If you are facing the car under the hood on the left side there is a metal tube, at least on mine, that screws on to the carb and goes down to the intake manifold and looks like it use to connect to it somehow though now its just hangs there and has since I got the car...


I found out that line is a vacuum line...I think. My question is what does it do and is it necessary or better to have it hooked up?

https://www.google.com/url?sa=i&rct=...14840941861422

Is it shown in the diagram at the link? If so , it is possibly a crank case vent tube going from the bottom center of the carb spacer to the passenger side valve cover. I took a second look and the diagram at the link is of a 390 truck engine so this may or may not be helpful.

Bob

[kirk]

If you are facing the car under the hood on the left side there is a metal tube, at least on mine, that screws on to the carb and goes down to the intake manifold and looks like it use to connect to it somehow though now its just hangs there and has since I got the car...


I found out that line is a vacuum line...I think. My question is what does it do and is it necessary or better to have it hooked up?

Yes, a picture is definitely in order. You say it screws on. With a compression nut? I think you are looking at the choke tube that would go from the round black choke spring housing on the carb to the exhaust manifold, but I can't say for sure without seeing it. If it is this, the vacuum sucks air thru the exhaust manifold to heat the choke and open it.

Look at the next to last engine picture here http://homepages.wmich.edu/~dillery/3Z68G516447.html to see mine. It's on the driver's side on my car because the carbs are mounted backwards.

[chief455]

re reading his post, going 'down the intake manifold' heck, it could be vacuum modulator to transmission.
want an answer = post a picture :-)

[gdmjoe]

Tube (enclosed in an asbestos (?) woven covering) had a nipple that seated into the exhaust manifold and allowed heat to be transferred to the choke mechanism. Caused the coiled spring inside to open the choke inside of the carb' as the engine warmed-up.
.

[Matt34]

Here are a couple of pictures. The carb is a new reman i bought when i first got the car and is very similar to the one that was on it. The line is metal and has that cloth heat shield on it and it was like that when I got the car.

Just hanging there but looks like it use to insert in that fitting just below where it cuts off. But I'm not really sure, when I got the car they didnt even have the firing order right so who knows.

Thanks for the help.

[Matt34]

Found a 41 inch SK 600 ft lb torque wrench with a micrometer on it in a pawn shop today and got it for 150 bucks. Owners manual, case and all. 3/4 inch drive. Last years model.

Feeling pretty stoked about it.

Just thought I'd share

[Marauderjack]

That tube looks like an exhaust manifold "Heat Tube" for the choke!!