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Old 10-16-2018, 06:23 PM   #1
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Default Engine power loss

Hello to all,
I’m new to ih forums and the web forums all together. A few months ago I purchased a 78 Scout -345 -2210 carb - I believe a Holley distributor.
I’m have a loss of power and the engine doesn’t seem to want to go and starts to stall out when accelerating. This occurs after I let it warm up for approximately 10-15 minutes, then I drive it for about ten minutes and the problem shows up. I have cleaned the contacts inside of the dizzy cap, put in a new ignition control box, ignition coil and condenser. I looked for vacuum leaks and changed a few old tubes. The truck starts and warms up great choke and high idle work. I had a stuck fuel pump in the carb but cleaned that out and it appears to operate as intended. There is a box on the fire wall that a vacuum line goes to and a tube to a a side of the carb to the acceleration control. I know that’s not what it’s called but the name of all that escapes me right now. This does not seem to be working but the diaphragm part on the carb seems to work fine. If I connect true vacuum to it it stays open. I was unable to find the valve or the box behind located on the firewall anywhere on line. But my understanding is that this should not effect my engine or cause the problem I’m having. I did want to make sure I had it plumbed right the vacuum diagram is not clear on where they plug In. The top port was whistling pretty good(vacuum leak). So I plugged it and I still have this issue. I do smell a lot of gas/ exhaust. I thought it was because the weather stripping is missing from the rear hatch. But I think is more then that. I can smell it in the engine compartment. But not leaks. I have also tested the ERG Valve and it appears to also operate properly, opening when accelerating. I have changed the fuel filter and spark plugs. Plugs where not fouled and a nice dark tan color. I don’t want to keep throwing parts at it. Any help would be appreciated
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Old 10-18-2018, 04:04 PM   #2
Robert Kenney
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Default Re: Engine power loss

Sounds a lot like fuel starvation. Check all of your fuel filters and if you can, verify fuel pressure at the carburetor fuel inlet.
Robert Kenney

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Old 10-19-2018, 01:48 PM   #3
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Default Re: Engine power loss

Thanks. Donít u think if it was a fuel issue it would happen all the time not just after it warms up. I did change the fuel filter before the carb. Is the another one somewhere? To up date this, I went back the next day and now it wonít start. Seems to start to fire but when I let the key go it dies. The power issue seemed to take a shorter time to appear the last few times I ran it. Iím thinking this is was my Holley distributor going bad and now itís shot after I changed the coil, condenser, and gold box. Do you think that could be the case? It ran after I changed all that stuff then the next day noit wonít start. Iím thinking I will change the dizzy out with a all in one more reliable unit.
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Old 10-19-2018, 06:28 PM   #4
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Default Re: Engine power loss

You might have a problem with your ignition switch if the engine dies when you let off the starter. You obviously need power going to the coil in both the START position and the ON position. If the coil isn't receiving power in either of those modes, you don't have a running engine.
Coal Trickle - '99 Dodge Ram SLT 2500 Q-Cab SWB 4x4 - 5.9L 24V CTD/NV4500/8800# GVW/12K# winch
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