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I just rebuilt my first engine it has 0 miles on it. It's in my 1968 F250 Camper Special. I had a friend help me rebuild the carburetor. Now there is fuel coming through the spark plug threads and everywhere else in the engine. I pulled the oil dipstick and the break in oil is no longer Royal Purple anymore and smells strongly like fuel. The engine has only been started maybe 4-5 times. It won't idle (think cuz of to much fuel and timing isn't set yet) it's what we were trying to do before seen the fuel coming out the plugs. I've never seen this before and asked friends but they don't know either. I'm hoping to get some ideas from here. I'm sure it has to be the carburetor but not sure what. I'm also having issues with the vacuum lines. Not sure how they go back together. If anyone can please help me.
if he rused old float it could be cracked and not Floating . check that first
If it floats
2nd you need to look up the float height for your carb . then lightly push needle down with finger and measure top lip of carb to top of float . this should equal your carb float height , if not bend float arm till it does match .
Hmmm. Remove the spark plugs and just for a couple revolutions of the engine spin it over so the gas will come flying out of the cylinders. There was so much gas in there it went past your new rings and in to the oil. Too much fuel in the cylinders has to come from the carb. When it was idling was there a bunch of gas coming out of those two bowl vent holes top front of the carb's air horn? Does that float feel heavy? Soaked inside with gas. It should feel light as a feather.
Thank you for the responses. The float is solid, but still floats. The fuel pump isn't new but is still good. Wasn't long before I started the rebuild, the pump was bought. I checked everything in the carb from the little rod and bearing to the needle and float. The only thing that wasn't replaced on the carb was the jets I believe. That's because the jets (or maybe jet ports) were truly impossible to get out. The flat-head part was risk of stripping. I've never rebuilt a carb before, so this is honestly new grounds for me. I'm almost ready to give up on this carb and get another. Just hard to find one that's manual choke.
Thank you for your response. That is a very good question. I honestly don't know that answer. Seems I'm going to have to take that carb apart and see if that gasket is in there. I'm not sure how to tell if there's fuel coming from the vents. This is my first time rebuilding a engine, so I'm not caught up with all the tricks of the trade. I don't know how to make fuel go through the carb without turning the engine over. I'm afraid to do it again, I really don't want to hurt the engine more than I probably already have. Any ideas would be grateful and helpful. Thank you again for all your help.
I think your problem is related to the power valve, there are 2 different gaskets that are used depending on the style of the valve. Remove the cover and if there is fuel inside the cover that is where the problem is. Look at the gaskets that came with the kit, one has a round hole and the other has a triangular hole.
The wrong gasket lets fuel pour into the manifold.
The only way to get gas out of the carb and down the intake, to the cylinders,without the engine running, is if the intake and carb got hot and percolated the gas out of it.
1. oil change 2. remove spark plugs to let fuel from cylinders evaporate then add a small amount of oil or wd 40 to hte cylinders and replace plugs. I would then get a new rebuilt carb or have a professional rebuild it. We all worry about spending the bucks but sometimes it costs to do it right and save having to spend more to fix our screw ups.
It's important - critical- to get the engine started right away and cam broken in on a rebuilt engine. But you knew that already. Mike at Mikes Carburetors suggests replacing those plastic floats with a brass float. Probably best to replace needle and seat on a carb rebuild. These are new correct? Always check the fuel height in the bowl as the final test, that's what counts. The float height is a ballpark setting just to get started. If the float is bad it could flood.
With all that said it's adviseable to find a carb that you know is working properly, that would be the one to use for engine break in.