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Stumped on poorly running 289 in 65 FB

1.5K views 22 replies 12 participants last post by  Phydeauxman  
#1 ·
I have the original 289 in my 65 FB. It has been rebuilt but has been a great running engine since I have owned the car. Not an original 4BBL car but now has a 4BBL intake with a 4100 carb. Car was running great when I put it away for winter but now is hard to start, won't idle and when running...runs rough. Has smoke coming from the exhaust but hard to tell the color since I can't keep the car running to go stand behind it to look. Pulled all of the plugs and they were wet with gas. Dried them all and made sure I had spark from coming from plug wire. Car has a points distributor.

I had put fresh ethanol free gas in it when I put it away for winter and added Stabil to the gas. I did run it after putting the fresh gas in it and it was running fine.

Normally, this car fires right up and idles with no problem. What should I check next?
 
#6 ·
Throwing a rebuild kit into the carb now. When I pulled the carb off the intake, the entire bottom of the intake was wet with fuel
 
#7 ·
Might check oil to make sure there’s no gas in there.
 
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#9 ·
Gas mixes with oil, so.....
"Did that and did not see any"
should be didn't smell any.
 
#10 ·
I agree with the cleaning the carb camp. Verify the choke 'n float settings etc. I've never experienced what you experienced in a 3-4 mo. winter lay over, though and I run 91-93 fuel that's 10% ethanol. Change your inlet filter too with a metal version, they are safer. Keep us posted.
 
#12 ·
Before you pull the carb down, here's an old trick, Take a medium sized wrench, hold it loosely, and give the carb a few sharp raps behind the fuel inlet, over the area where the needle valve is. Sometimes the little shock is enough to un-stick the needle valve. It's usually a small piece of dirt, or the valve dried out through evaporation and stuck in a position. It works 90% of the time and saves you from a rebuild kit when you tear the gasket removing the top of the carb.
 
#13 ·
Try the float tapping technique, you can also trickle B-12 into the car if you get it to idle. Once it idles you will want to change your oil if is smells like gas. Your plugs should clean themselves up with driving.
 
#14 · (Edited)
Surprised you're having issues, given the "real" gas and the short amount of time stored.
Scrutinize the needles and seats that are currently in the car. Kit suppliers have gone to viton for the needle material, but as far as I'm concerned,
it may not be the bitchin' stuff it's made out to be.
I've got original needles and seats from the 60's in my '66. Works fine, even with the crappy, ethanol-heavy stuff that passes for "gasoline" in California.
I resisted the kits when I went through the carb many years ago and just cleaned it and replaced the top gasket.
These are the needle and seats that are on my carb- C2AZ-9564-B. Don't know what needle material is on those but the longevity is outrageous.
They pop up from time to time on eBay.

 
#15 ·
My 4100 sat for 2 years, empty and cleaned out. The secondary viton needle was “stuck” when I took it apart a few weeks ago. Just sitting there it left a “ring” imprinted on the viton coated area. Rebuild kits was a good one from Mike’s carbs.
 
#16 ·
Rebuilt the carb and now she is running great again. I have had this car for 13 years now and I literally just drove it down the road for the first time. I have done TONs of work to it since owning it but the motor was running when I bought it. I did have the stock heads completely gone thru, added long tube headers/full exhaust, 4BBL intake and carb, T5 transmission, and installed a built 8" chunk that has 3.55 gears in it. I have to admit...pretty disappointed in the power the car has. It runs really good and cruises down the road great but I could barely get it to do a burnout from a dead stop in 1st gear and it would not break the tires loose at all on a hard 1 to 2 shift. Not sure where to start on trying to get more power from what I have. When I rebuilt the carb, I tried to dial the choke in. It has a manual choke that used to have a heat tube that ran from the bottom of the choke assembly to a fitting on the exhaust manifold. Had to remove the tube when I went to headers. It also has metal clip mounted to the choke assemble that the heater hose sits in that keeps the hose pressed to the side of the plastic choke housing. I am assuming that the once the hose is passing hot water that the choke would open. Not sure if any of this is working but with the car cold, the choke blade sitting above the primaries is closed. I thought once the motor heats up, the blade would open but when I got back from driving the car the blade was still closed.
 
#17 ·
With a 5 speed and 3.55 gear it should be able to fry the tires and bark 2nd!!
What is your timing set at? Both initial and full advance? What distributor are you using?
Stock camshaft?
 
#18 ·
Yeah, that is my thinking too. I will have to check the time but it has a stock style points distributor. I have another distributor to put in it that has been converted to Pertronix and has been curved by Dan at the Mustang Barn but I have to drop the pan to replace the oil pump shaft before I can do that. The person I bought the car from said they cam was replaced when the engine was rebuilt but that was before he owned the car and he had no details on it. It idles smooth like a stock cam.