Need Carb help.
FTE Legend
Joined: Nov 2015
Posts: 30,935
Likes: 4,124
From: Angier, NC
Thank you Lightning on the bowl vent hose & lever, thought it may have been just mine.
For my choke I am on the fence on how I am going to do mine.
Stock uses 7 volts off the ALT, yes 7 volts not 12 volts. It also uses hot (clean) air pulled from the air filter thru a metal tube that runs thru the exh. manifold to heat it up then up to the choke housing. The 2 work together to open the choke. You can run into issues is you only run 1 or the other.
I may go stock but I plan on a 3G ALT and have to look into picking up 7 volt power.
I am also running EFI exh. manifolds and they do not have the pass thru of the metal tube for hot air. The work around is get copper tubing and wrap it around the manifold to heat the air. Then it would work like the stock set up, just does not look too good in my book.
Another way is to replace the black 7 volt cap on the choke with a 12 volt one, plug the air tube hook up at the carb as you will have a vacuum leak, run 12 volts with motor running (relay) to the new cap and be done.
This is the way I am leaning to go.
Dave ----
For my choke I am on the fence on how I am going to do mine.
Stock uses 7 volts off the ALT, yes 7 volts not 12 volts. It also uses hot (clean) air pulled from the air filter thru a metal tube that runs thru the exh. manifold to heat it up then up to the choke housing. The 2 work together to open the choke. You can run into issues is you only run 1 or the other.
I may go stock but I plan on a 3G ALT and have to look into picking up 7 volt power.
I am also running EFI exh. manifolds and they do not have the pass thru of the metal tube for hot air. The work around is get copper tubing and wrap it around the manifold to heat the air. Then it would work like the stock set up, just does not look too good in my book.
Another way is to replace the black 7 volt cap on the choke with a 12 volt one, plug the air tube hook up at the carb as you will have a vacuum leak, run 12 volts with motor running (relay) to the new cap and be done.
This is the way I am leaning to go.
Dave ----
FTE Legend
Joined: Jul 2010
Posts: 32,875
Likes: 48
From: Northeast, OK
Dave - According to what I've read, such as this, the 3G does have a stator terminal where you can get 7 volts to power your choke's heater. Should be easier than rigging up a relay, but either way works.
On the exhaust, it doesn't look like the 4.9L got EFI until '87, so I didn't put that illustration on my web site. But, you can see it on Page 20 of Section 52.2 in the Illustrations.
On the exhaust, it doesn't look like the 4.9L got EFI until '87, so I didn't put that illustration on my web site. But, you can see it on Page 20 of Section 52.2 in the Illustrations.
FTE Legend
Joined: Nov 2015
Posts: 30,935
Likes: 4,124
From: Angier, NC
Thanks Gary, I remembered you guys posting about the 7 volts from the 3G ALT.
Thing is I would also need to wrap copper tubing around the EFI manifold up to the choke also as the 2 work together to open the choke. I just don't like the copper wrap as it will look hooky.
That is why I want to go with a 12 volt black cap and so it will only get power when running a relay will be used to power the cap.
Thanks for the exh page, will have to give it a look over.
Dave ----
Thing is I would also need to wrap copper tubing around the EFI manifold up to the choke also as the 2 work together to open the choke. I just don't like the copper wrap as it will look hooky.
That is why I want to go with a 12 volt black cap and so it will only get power when running a relay will be used to power the cap.
Thanks for the exh page, will have to give it a look over.
Dave ----
Moderator
Joined: Jan 2001
Posts: 56,995
Likes: 2,741
From: Virginia
The best way to run a 12v choke is to run it through a oil pressure switch. If you hook it to key on power, and for some reason you have a little trouble starting the engine, all that time you are messing with the engine with the key on cranking it over, the choke is getting power and is starting to open up, but the engine is dead cold and hasn't run. This can aggravate your starting problem.
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