Vacuum hose problem where does it go
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Vacuum hose problem where does it go
I have a 1976 Ford Ranger 250 XLT trailer special. I have a 460 motor with a carter afb carburator. I need to pass smog soon but I have a hose plugged up in the front of the carburator between the mixture screws ( the biggest outlet) I need to hook this up correctly and find out where it goes to. The hose is plugged with a bolt at this moment.
Thanks for any information.
Thanks for any information.
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This is the way the truck came when I got it. I have the brake booster going to the back of the intake manifold in a metal tree. The pcv valve is going out the back of the carburator. There is a pluged vacuum on the front of the carburator.
I can not find any reference to a Carter AFb carburator in any of my manuals for this truck. I have seen them on other ford truck of similar years they are stock I hope not aftermarket?
I seemed to have a lack of brakes when I was pulling a Fifth wheel trailer could connecting the brake booster Vacuum to the back of the carburator help this. My brakes work adequate under normal load but I was going to replace the brake master cylinder to hopefully get a little more stopping power when I pull a fifth wheel.
I can not find any reference to a Carter AFb carburator in any of my manuals for this truck. I have seen them on other ford truck of similar years they are stock I hope not aftermarket?
I seemed to have a lack of brakes when I was pulling a Fifth wheel trailer could connecting the brake booster Vacuum to the back of the carburator help this. My brakes work adequate under normal load but I was going to replace the brake master cylinder to hopefully get a little more stopping power when I pull a fifth wheel.
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From: Blacksburg, VA
I think one of your problems is that the brake booster is going to a tree off the manifold, and not directly from your carb. The large connection at the back of most carbs is strictly for the brake booster - the booster has such a large hose because it requires a significant vacuum connection to the carb.
Take the PCV off the back of the carb and route to the front (like it should be). Connect the brake booster to the back of the carb, and plug the leftover hole in the vacuum tree.
See if that improves braking.
Take the PCV off the back of the carb and route to the front (like it should be). Connect the brake booster to the back of the carb, and plug the leftover hole in the vacuum tree.
See if that improves braking.
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From: Louisville,Ky.
It is an extra port. I would use the port in the front for the PCV, remove the fitting in the rear of the carb and put a pipe plug in it and leave the brake booster on the intake manifold tree where it belongs. The rear threaded port is an extra incase you do not have a port in the intake manifold to draw vacuum for the brake booster.
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From: Warrenton, VA
My truck's brake booster line is off the tree fitting in the back of the intake.
Plus, the brake booster requires straight manifold vacuum. Why would it make a difference where it was connected, so long as it's to manifold vacuum and the line and fittings are of relative size.
I've got factory ford manuals for a '79. I'll see if by anychance there are vacuum diagrams in them that may help.
Do you have a working electronic brake controller for trailer brakes? How are the brakes on the trailer? That may also help while towing.
Another question, in my area, vehicles over 25 years of model year date are exempt from emissions/smog testing. Is it something you're required to have done?
Plus, the brake booster requires straight manifold vacuum. Why would it make a difference where it was connected, so long as it's to manifold vacuum and the line and fittings are of relative size.
I've got factory ford manuals for a '79. I'll see if by anychance there are vacuum diagrams in them that may help.
Do you have a working electronic brake controller for trailer brakes? How are the brakes on the trailer? That may also help while towing.
Another question, in my area, vehicles over 25 years of model year date are exempt from emissions/smog testing. Is it something you're required to have done?
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From: Blacksburg, VA
Tapping the brake booster from manifold vacuum is not a great idea. You might not think it makes a difference, but think about it: you're pulling vacuum from a single cylinder runner on the manifold (depending on port location). If you connect to the carb, you've got almost continuous, linear vacuum. Its not necessarily dangerous, but its certainly a reason why you're braking might be bad when towing.
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In theory, Your set-up can't be much different than this one.
http://mil1ion.clubfte.com/FordVacuumDiagrams.html
http://mil1ion.clubfte.com/FordVacuumDiagrams.html
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Originally Posted by Mil1ion
In theory, Your set-up can't be much different than this one.
http://mil1ion.clubfte.com/FordVacuumDiagrams.html
http://mil1ion.clubfte.com/FordVacuumDiagrams.html
Did these trucks come with a carter AFB carburator out of the factory ? My carburator has 8 mounting holes like it might be a universal fit carb. The linkage appears to be original. I can find no reference to a carter 4 barrel in any of my ford reference manuals.
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From: Brentwood,CA
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Originally Posted by ford390gashog
I wonder if I can pass california smog with this Carter AFB carburator?
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Originally Posted by ford390gashog
I wonder if I can pass california smog with this Carter AFB carburator?
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