The Stovebolt Site Forums The Shop Area Engine Shop Runs Great, but no Power. Now what?

Just got my full pressure 235 running that was in my 1951 3600. Got it to idle smoothly with timing, mixture and idle screw set. Went to take it on the road, and would not carry itself up any hill, and would die as you would depress the clutch in to come to a stop. No idea if its just not making power or if it is something beyond a timing issue. Any suggestions help! Thanks folks.

Verify the carb is getting plenty of fuel, running lean will cause this.
Verify the timing is close to spec's, it could idle fine and still be off to far to make power.

How does it respond ? buck around, backfire, list all the symptoms, how does it start up once it dies?
Whats the history of carburetor? fuel pump? fuel lines? tank?
What color are the sparkplug tips?

Joe

Carb gets plenty of gas (we pulled the fuel line and cranked it over to check this). When stopped the engine will rev very high and smooth with no hesitation or sputter. Will have to get the book out to double check the specs as far as timing and so on.

When it does die though it sputters and bucks, no real back fire, just seems like it doesn't want to go anymore. I had it running just fine and was able to use it as a daily driver several months back till this issue came up. Once it dies it will start by dropping the clutch or by cranking it but battery dies after so many tries.

History of the carb is brand new, same with fuel pump and spark plugs. Spark plugs are sooty but seem to spark just fine when tested. As far as the fuel lines and tank, all are original and there was some gunk in the tank and lines which I put a filter right before the fuel pump to help this.

Right now I'm not sure if the vacuum advance is work so I got one on order and will install asap. But that's the only think I could think of to try, Seeing as I'm only 20 and this is my first and probably lengthy attempt to restore my first truck.

I suspect, since it idles, that the ignition's advance mechanism isn't working.

Three things have to be right to get good performance- - - - -fuel, spark, and valve timing. Unless you've had the camshaft out of it recently, the cam timing isn't likely to be an issue, but it never hurts to check. Pull the valve cover off, and watch the valves on the #6 cylinder. The exhaust valve will close, and the intake will just begin to open as the #1 and #6 pistons reach the top of the stroke. The distributor rotor should be pointing toward the #1 plug wire terminal as the #6 valves overlap, also, so it's a good way to confirm you've got the distributor timed right at the same time. If the dizzy is timed a tooth late, it's still possible for the engine to run, but poorly.

The most likely problem is going to be a fuel-related problem. If the plugs are black and sooty, that indicates the mixture is too rich. Check the carburetor float to see if it's got a leak. A heavy float will allow the fuel level in the carb to get too high and spill over into the intake, causing an over-rich condition. That will produce the stumble and stall you're experiencing, and a major power loss. Look down the carb throat at idle, and see if fuel is percolating out of the nozzle in the venturi, about halfway between the air horn and the throttle plates. If so, you've found your problem.
Jerry

Have you changed the filter you installed. It doesn't take much to stop up on the vacuum side of the pump. I install reproduction gas tanks on all my 50's vehicles because I have never seen one that I considered clean after 50 years of rust and lead sediment. The vacuum advance actually allows the centrifugal advance to advance as rpm goes up and retards it under load demand when vacuum drops. You can check the vacuum advance by revving the engine up and letting off. It should move the distributor. The centrifugal advance is under the breaker plate. The best way is to put on a timing light, disconnect the line to the vacuum advance and see if it advances as you rev it up. Points corrode from sitting. I would replace them if you haven't. Spark plugs have to fire under pressure. Almost any plug will fire with no pressure. Are the plugs the correct heat range. I would invest in a set of plugs.

And stop worrying about being only 20 years old, we were all that old once! Check out the easy stuff first, if it was running everyday, that a good sign nothing major has happened. Go though the fuel system tank to carb, then the ignition circuit. One or both should fix it.

Joe

Thanks for the suggestions folks. Well I ordered a new vacuum advance and when it showed up it was different from the one on it. The difference was the collar that goes around the distributor was straight where as the one on it before was at a 45 degree angle, so this means that the collar adjustment screw and nut get in the way of the bolt that holds the distributor down, which in turn could round off the hold down bolt. Any ideas? is this new vacuum advance ok to use or should I look for one like what was on it. Also does the collar (C clamp type thing) really need to be there even?

Hot Rod and Crenwelge are heading you in the right direction. They helped me with some issues I had on my 64', and I value their input. The biggest thing to remember is that it's just a machine, and a man(and women)made it, so in time you'll get it figured out. Don't let it get the best of you, and keep your chin up...it makes a better target. Good luck and let everyone know what gets you going again so someone can learn from it.
Tramp

tho this post is a little older, I couldn't help but want to offer this tip. There's a guy on the internet that does AWESOME carb work, but better yet, will talk to you and help or even walk you through fixing your carb if you ask. He's got 48 years of doing carbs only, and used to race so he knows his stuff. try him. JBcarberators he even did fuel delivery work on Richard Petty's car and some others that I forget. He built my carb for my Harley and MAN I'm now thinking about seatbelts for it.LOL