49 8BA has no power

Vanspeed

Vanspeed

Well-known member
Hi guys. Working on a ‘49 F-1 that was parked in the late 60’s. The truck starts on the first crank and idles very nicely. Upon driving it has hardly any power. It does not sputter or backfire, just no power. If the road starts to climb it is almost impossible to get up it. Truck has new gas tank, new lines, in-line filter before pump. Compression on cylinders is 100,90,90,90,100,100,90,85. I have tried two different carbs. It has a Petronix ignition in the stock disrtibutor. Owner did not want to deal with points any more. I feel like the distributor is not advancing or possibly timing is off? I would think timing off would give me some backfires or rough idle but it does not. Lack of fuel? Any suggestions appreciated.
 
IIRC Pertronix systems are particular as to what coil and spark plugs wires are installed. Might be part of the problem or not. If it was me I'd replace the current distributor set up with a know good one and see if there is any improvement. JMO
 
The owner had some Fenton headers installed and new exhaust. Distributor is original and the fuel pump was the pump that was on it. I am thinking it is distributor not advancing or fuel. The distributor was not moved as it fired right up the first time we worked on it and you can tell it has not been messed with, what I mean by that is you can tell this distributor is in the exact spot it was in when new.
 
There seems to be a conflicting information here. Petronix is what you said it has, but then you say it has original ignition. Can't be both.
 
IME, retarded timing will often start and idle very well, will not backfire and lack power as RPM increases.

coincidentally, i just replaced my old distributor. i had concluded that it was failing to advance the timing properly, possibly due to binding weights.

power was lacking as the RPM increased due to misfires. the differing symptoms, yours simply lacking power, and mine misfiring, could be attributed to the richness of the mixtures between my carb and yours.....possibly. :)
 
The owner sent a carb to Charlie NY to rebuild and I was ready to install it when I noticed the carb he sent Charlie was an early carb, model 91-99, that doesn’t have the vacuum port and has the wrong air cleaner base so I couldn’t rule out it being a carb issue.
 
Vanspeed said:
The owner sent a carb to Charlie NY to rebuild and I was ready to install it when I noticed the carb he sent Charlie was an early carb, model 91-99, that doesn’t have the vacuum port and has the wrong air cleaner base so I couldn’t rule out it being a carb issue.
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That makes sense now. An 8BA needs that vaccuum port from the carburetor. Your ignition would then be advanceing correctly with the correct vacuum port.
 
Vanspeed said:
The owner sent a carb to Charlie NY to rebuild and I was ready to install it when I noticed the carb he sent Charlie was an early carb, model 91-99, that doesn’t have the vacuum port and has the wrong air cleaner base so I couldn’t rule out it being a carb issue.
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You might want to talk to Charlie again. I wouldn't be surprised if he wouldn't want to fix you up with a proper 8RT carb in exchange for the 91-99 for a reasonable charge. I think the "91-99"s are a little scarcer than the 8RT's.
 
tubman said:
You might want to talk to Charlie again. I wouldn't be surprised if he wouldn't want to fix you up with a proper 8RT carb in exchange for the 91-99 for a reasonable charge. I think the "91-99"s are a little scarcer than the 8RT's.
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Could you pass along Charlie’s email to me? I would be more than happy to swap out the 91-99 for the correct carb. Pm me if you can. Thanks.
 
Vanspeed said:
Could you pass along Charlie’s email to me? I would be more than happy to swap out the 91-99 for the correct carb. Pm me if you can. Thanks.
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cas5845@yahoo.com
Charlie.jpg
 
hueyhoolihan said:
IME, retarded timing will often start and idle very well, will not backfire and lack power as RPM increases.

coincidentally, i just replaced my old distributor. i had concluded that it was failing to advance the timing properly, possibly due to binding weights.

power was lacking as the RPM increased due to misfires. the differing symptoms, yours simply lacking power, and mine misfiring, could be attributed to the richness of the mixtures between my carb and yours.....possibly. :)
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Yup, good advice.
 
With the wrong carburetor, he has no advance at all. Let's see what installing the proper carburetor does before offering more advice.
 
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tubman said:
With the wrong carburetor, he has no advance at all. Let's see what installing the proper carburetor does before offering more advice.
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Denny, I'm not sure of the wording but in post #8 it seems like he's saying it has a correct 8ba carb (with port) on it currently, but the PO had mistakenly sent an early style carb for rebuilding. So the current owner now has that Charlie NY early carb sitting on the bench and can't use it as a tester as it doesn't have the vacuum port.
 
I have seen earlier carburetors installed on 8BAs with the vacuum advance tied into manifold vacuum. That results in the opposite of the advance curve you want.
Make sure your vacuum advance is good. Then use the correct carburetor with the advance connected to the port in the carburetor center section.
 
GB SISSON said:
Denny, I'm not sure of the wording but in post #8 it seems like he's saying it has a correct 8ba carb (with port) on it currently, but the PO had mistakenly sent an early style carb for rebuilding. So the current owner now has that Charlie NY early carb sitting on the bench and can't use it as a tester as it doesn't have the vacuum port.
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I don't read it that way, but it really doesn't matter because my point is you can't properly troubleshoot a problem on an engine that has known problem areas. Fix them first. It looks like he's gonna get the correct carb from Charlie, which should help a lot.
 
Yes the engine has the correct carb on it, the owner sent Charlie an earlier version as he was not aware that the 94 changed at all. I also suspect that the mechanical advance might be seized. I am checking that on Monday.
 
cadillac512 said:
The stock 8BA distributor has no mech advance. Only vac, so if it's not working you have no advance.
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that's my understanding too.

..and Google's AI confirmed it if that's of any significance. here is how i phrased my question to Google AI: "did the original 1949 ford 8ba distributor have a mechanical advance"

here's the response: "No, the original 1949 Ford 8BA distributor did not have a mechanical advance. It was a Load-O-Matic distributor that relied solely on vacuum advance for ignition timing adjustments. This type of distributor was designed to work with the original carburetor and wouldn't perform optimally with aftermarket modifications like performance camshafts or multiple carburetors."
 
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