The Ford Barn

Chappy · 08-10-2015, 06:24 PM

Being new to flatheads, and starting off with one that wouldn't run, I'm happy to say I've put around 1500 miles on it this summer with the help of you guys. My only issue that I need to resolve now is even warmed up to operating temperature (at the 1/2 mark) the engine starts breaking up at around 1/2 throttle. For instance when I'm cruising and I give it about 2/3 throttle or I'm trying to climb a hill the engine runs extremely rough, to me it seems like an ignition issue, my guess would be the vacuum advance or lack there of is my problem. It runs good up to that point. I'm running a 59A, 6V + ground, single Holley 94, petronix pointless module and petronix coil, stock trans and rear end in a 48 2dr sedan. I think my timing is about maxed out, as the screw is just about at the bottom of the opening, it seemed to run best at that setting, and doesn't ping. I'll also say I can cruise at 45mph for about a long time and my temperature stays at about 5/8 on the temp gauge, but if I go up to 50mph the temp goes to 3/4, not sure if that's a completely different cooling issue or timing related.

Charlie ny · 08-10-2015, 06:54 PM

Chap,
Root around and find a crab dist with points and a condenser, all in decent
condition then install a Car Quest 52-1902 coil ( internal resistor ) or equiv. Be sure
the pos terminal of the coil is attached to the dist.
Charlie ny

Chappy · 08-10-2015, 06:57 PM

Charlie, I still have the original coil off of the car, which I think is in good shape, will that work or should I go with the new coil?

GB SISSON · 08-10-2015, 06:58 PM

Could it be the power valve in the carb? I just rebuilt two of them and noticed there are two different valves in the kit and two different gaskets for them. It was confusing. From what I glean, these add extra fuel under the conditions you mentioned. No carb expert, just a thought from my recent experience.

Charlie ny · 08-10-2015, 08:29 PM

The coil I suggested , which I have had excellent results with , has the benefit of
an internal resister, you jump out your present resister. The stock dist and this coil
is where I'd start.
Charlie ny

GB SISSON · 08-10-2015, 09:14 PM

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Quote:

Originally Posted by Charlie ny

The coil I suggested , which I have had excellent results with , has the benefit of
an internal resister, you jump out your present resister. The stock dist and this coil
is where I'd start.
Charlie ny

I must add that on my very first venture into 'town', 12 miles away, I was running on an original ford coil because I liked what it looked like. I broke down twice and had to be pushed off the road by good samaritans, I got a ride to our only auto parts store, a napa and bought a 6v coil with internal resistor (because that's all they had.) I bypassed the resistor by stacking the wire on top of the other one and boom, she fired right up and I never looked back. Drove home on my own four wheels.

Mart · 08-11-2015, 09:03 AM

I have had a problem like this a few times and it has been problems with the HT side of the ignition. I run the crab caps and they can and do fail. I also had a rotor arm that failed.

Your description of being able to run at light throttle and things go wrong when warmed up and applying more pedal sounds very much like my problems. I would get a new crab cap and rotor, and the clip kit to fit them (if you have the rabbits ears type cap) and a new set of leads and try that.

You might be able to detect marks inside the cap caused by stray sparks.

Mart.

47COE · 08-11-2015, 07:00 PM

Bad fuel pump could act like that too. Years ago an International pickup had similar symptoms. A new fuel pump fixed it.

08-10-2015, 06:24 PM	#1
Chappy Member Join Date: Nov 2014 Location: Rochester, NY Posts: 55	59A Breaks up around 1/2 throttle Being new to flatheads, and starting off with one that wouldn't run, I'm happy to say I've put around 1500 miles on it this summer with the help of you guys. My only issue that I need to resolve now is even warmed up to operating temperature (at the 1/2 mark) the engine starts breaking up at around 1/2 throttle. For instance when I'm cruising and I give it about 2/3 throttle or I'm trying to climb a hill the engine runs extremely rough, to me it seems like an ignition issue, my guess would be the vacuum advance or lack there of is my problem. It runs good up to that point. I'm running a 59A, 6V + ground, single Holley 94, petronix pointless module and petronix coil, stock trans and rear end in a 48 2dr sedan. I think my timing is about maxed out, as the screw is just about at the bottom of the opening, it seemed to run best at that setting, and doesn't ping. I'll also say I can cruise at 45mph for about a long time and my temperature stays at about 5/8 on the temp gauge, but if I go up to 50mph the temp goes to 3/4, not sure if that's a completely different cooling issue or timing related.

08-10-2015, 06:54 PM	#2
Charlie ny BANNED Join Date: May 2010 Posts: 3,019	Re: 59A Breaks up around 1/2 throttle Chap, Root around and find a crab dist with points and a condenser, all in decent condition then install a Car Quest 52-1902 coil ( internal resistor ) or equiv. Be sure the pos terminal of the coil is attached to the dist. Charlie ny

08-10-2015, 06:57 PM	#3
Chappy Member Join Date: Nov 2014 Location: Rochester, NY Posts: 55	Re: 59A Breaks up around 1/2 throttle Charlie, I still have the original coil off of the car, which I think is in good shape, will that work or should I go with the new coil?

08-10-2015, 06:58 PM	#4
GB SISSON Senior Member Join Date: Jan 2014 Location: Orcas Island Washington Posts: 4,926	Re: 59A Breaks up around 1/2 throttle Could it be the power valve in the carb? I just rebuilt two of them and noticed there are two different valves in the kit and two different gaskets for them. It was confusing. From what I glean, these add extra fuel under the conditions you mentioned. No carb expert, just a thought from my recent experience. __________________ Owner/Operator of 'Jailbar Ranch' on the side of Mt. Pickett. Current stable consists of 1946 1/2 ton pickup turned woodie wagon with FH V8, 1947 Tonner Pickup (red) mostly stock with exception of a cummins 6at turbo diesel, 1946 Tonner Pickup (green) with 226 cu in 6 cyl flathead, 1979 Toyota landcruiser wagon, completely encased in 1947 Ford Jailbar sheet metal. Ok, cornbinder rear fenders..... 'Rusty ol' floorboards, hot on their feet' (Alan Jackson)

08-10-2015, 08:29 PM	#5
Charlie ny BANNED Join Date: May 2010 Posts: 3,019	Re: 59A Breaks up around 1/2 throttle The coil I suggested , which I have had excellent results with , has the benefit of an internal resister, you jump out your present resister. The stock dist and this coil is where I'd start. Charlie ny

08-11-2015, 09:03 AM	#7
Mart Senior Member Join Date: May 2010 Location: Solihull, England. Posts: 8,749	Re: 59A Breaks up around 1/2 throttle I have had a problem like this a few times and it has been problems with the HT side of the ignition. I run the crab caps and they can and do fail. I also had a rotor arm that failed. Your description of being able to run at light throttle and things go wrong when warmed up and applying more pedal sounds very much like my problems. I would get a new crab cap and rotor, and the clip kit to fit them (if you have the rabbits ears type cap) and a new set of leads and try that. You might be able to detect marks inside the cap caused by stray sparks. Mart.

08-11-2015, 07:00 PM	#8
47COE Senior Member Join Date: Apr 2011 Location: Oregon Posts: 220	Re: 59A Breaks up around 1/2 throttle Bad fuel pump could act like that too. Years ago an International pickup had similar symptoms. A new fuel pump fixed it.