The Ford Barn

rotorwrench · 02-27-2019, 07:23 PM

If you have to adjust the idle up then something is sure wrong. Vacuum leak could be a factor. Some of those old manifolds can leak internally. Some of the ones in the 21 stud era were problematic that way.

Tinker · 02-27-2019, 08:34 PM

Drbrown and Drolston have a great method to follow. Once you get it running at a reasonable running rpm then you can fine tune with a vacuum gauge. I agree with a turn and a half or quarter.

Then when that is sorted and you are still having issues with power acceleration under load. Try MMO down the carb when running, or a new condenser (maybe a couple as they are bad out of the box).

I know the MMO treatment is pretty joked about, but my rebuilt 81a stumbled under load and bucked. After a couple of smoke outs it freed up the valves that were sticking. Only do it once a yr now, but it runs well under load.

30AAFord · 02-28-2019, 10:57 AM

New fuel pump is from Mac's - went with later glass bowl style (that's what was on the engine when I got it and liked the ability to check sediment collection). Have not tested pressure.

I can see no open ports on the 59A base, but will check again when I see the truck next.

Don't have a vacuum gauge, but looks like I need to get one. How am I hooking the vacuum gauge to fine tune carb? Am I using the port on intake that connects to vacuum advance line for distributor?

petehoovie · 02-28-2019, 02:04 PM

Disconnect the vacuum line to the windshield wiper motor and connect your vacuum gauge at that point....

Mike in AZ · 02-28-2019, 03:51 PM

Have had reports of new fuel pumps putting out too much pressure, causing flooding. Good luck on figuring out solution(s) to you problem. Mike

30AAFord · 02-28-2019, 04:06 PM

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Petehoovie - thank you, will get a vacuum gauge and do that.

Was given a box full of old fuel pumps - could always swing test a few of those out if the vacuum test comes back negative and carb adjustments do nothing.

02-27-2019, 07:23 PM	#21
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 16,422	Re: Idle Screw - Running Issue on a '33 BB If you have to adjust the idle up then something is sure wrong. Vacuum leak could be a factor. Some of those old manifolds can leak internally. Some of the ones in the 21 stud era were problematic that way.

02-27-2019, 08:34 PM	#22
Tinker Senior Member Join Date: May 2010 Location: MN Posts: 7,053	Re: Idle Screw - Running Issue on a '33 BB Drbrown and Drolston have a great method to follow. Once you get it running at a reasonable running rpm then you can fine tune with a vacuum gauge. I agree with a turn and a half or quarter. Then when that is sorted and you are still having issues with power acceleration under load. Try MMO down the carb when running, or a new condenser (maybe a couple as they are bad out of the box). I know the MMO treatment is pretty joked about, but my rebuilt 81a stumbled under load and bucked. After a couple of smoke outs it freed up the valves that were sticking. Only do it once a yr now, but it runs well under load. Last edited by Tinker; 02-27-2019 at 08:48 PM.

02-28-2019, 10:57 AM	#23
30AAFord Member Join Date: May 2010 Location: Massachusetts Posts: 72	Re: Idle Screw - Running Issue on a '33 BB New fuel pump is from Mac's - went with later glass bowl style (that's what was on the engine when I got it and liked the ability to check sediment collection). Have not tested pressure. I can see no open ports on the 59A base, but will check again when I see the truck next. Don't have a vacuum gauge, but looks like I need to get one. How am I hooking the vacuum gauge to fine tune carb? Am I using the port on intake that connects to vacuum advance line for distributor?

02-28-2019, 02:04 PM	#24
petehoovie Senior Member Join Date: May 2015 Posts: 8,076	Re: Idle Screw - Running Issue on a '33 BB Disconnect the vacuum line to the windshield wiper motor and connect your vacuum gauge at that point.... __________________ The only thing nice about being imperfect is the joy it brings to others.... *"Silver rings, your butt! Them's washers!"* "We shot our way out of that town for a dollar's worth of steel holes!" - from 'The Wild Bunch' - 1969 https://www.youtube.com/watch?v=7NReUd2_0u0

02-28-2019, 03:51 PM	#25
Mike in AZ Senior Member Join Date: May 2010 Location: Waddell, AZ Posts: 2,540	Re: Idle Screw - Running Issue on a '33 BB Have had reports of new fuel pumps putting out too much pressure, causing flooding. Good luck on figuring out solution(s) to you problem. Mike

02-28-2019, 04:06 PM	#26
30AAFord Member Join Date: May 2010 Location: Massachusetts Posts: 72	Re: Idle Screw - Running Issue on a '33 BB Sponsored Links (Register now to hide all advertisements) Petehoovie - thank you, will get a vacuum gauge and do that. Was given a box full of old fuel pumps - could always swing test a few of those out if the vacuum test comes back negative and carb adjustments do nothing.