Cylinders washed need help

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Ryanbrown36

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I’ve recently completed my Sbc swap and just threw a new carb on it and it fired right up but was running a little rich, I went out yesterday to adjust the carb and I couldn’t get it to start after leaning it out (it was also very cold out) so played around with it and put it back to where it was set at before and didn't want to start and I now smell gas on the dipstick, I’m guessing I’ve cranked for maybe a little over 1 minute total (probably giving more gas than I should be but wasn’t thinking and I’m new to all this) how worried should I be, and what can I do now to fix this. Thanks
 

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The easy solution is change the oil. But it’s subjective. I can’t imagine it dumped that much gas past the rings.
But did you pull some plugs and confirm that it was grossly flooded?
Also gasoline evaporates, so even if you have some gas in the oil, it will effectively disappear.
 

Ryanbrown36

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The easy solution is change the oil. But it’s subjective. I can’t imagine it dumped that much gas past the rings.
But did you pull some plugs and confirm that it was grossly flooded?
Also gasoline evaporates, so even if you have some gas in the oil, it will effectively disappear.
I didn’t at the time but I just pulled #1 plug and this is how it looks. I honestly don’t think there could’ve been much that got past either but it’s basically it a fresh motor and don’t want to do any damage.
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It is possible to wash rings out of a new engine. Way rich, although probably no damage has been done yet need to fix whatever is causing it. Hard to see what carb is on it Carter?
 

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It is possible to wash rings out of a new engine. Way rich, although probably no damage has been done yet need to fix whatever is causing it. Hard to see what carb is on it Carter?
It’s a Holley 600 cfm street warrior, when it first ran the accelerator pump was way off but did run fine just high idle, if I lean it out and set the accelerator pump and idle to a factory setting would you recommend trying to start it or are there other steps first?
 

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check fuel level/float/ idle mixture, running. Should be fuel just below opening, side of bowl. Accelerator pump only works during acceleration. Idle mix screws adjust after float level. Gradually lean them out until RPM drop then out 1/8th to 1/4 turn. May need to go back and forth or side to side a couple times.
 

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check fuel level/float/ idle mixture, running. Should be fuel just below opening, side of bowl. Accelerator pump only works during acceleration. Idle mix screws adjust after float level. Gradually lean them out until RPM drop then out 1/8th to 1/4 turn. May need to go back and forth or side to side a couple times.
I already set the float height like how you said and did the mixture screws, I will adjust more like you are saying when it runs again. Do I need to do anything about the cylinder wash or do I just need to get it running again and tune from there?
 

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Change the oil if you're concerned.

From the specs in your other thread it's probably gonna want a lot of idle timing. Make sure the vacuum advance is hooked to manifold vacuum.

I square up the transfer slot and adjust idle speed with the rear secondary screw from underneath. Sometimes it's a straight screw and sometimes it's an allen head. After adjusting the mixture screws you may have to go back and readjust. I shoot for highest vacuum using a gauge. Base setting on a 2 corner idle is 1.5 turns out.
 

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Change the oil if you're concerned.

From the specs in your other thread it's probably gonna want a lot of idle timing. Make sure the vacuum advance is hooked to manifold vacuum.

I square up the transfer slot and adjust idle speed with the rear secondary screw from underneath. Sometimes it's a straight screw and sometimes it's an allen head. After adjusting the mixture screws you may have to go back and readjust. I shoot for highest vacuum using a gauge. Base setting on a 2 corner idle is 1.5 turns out.
Ok thank you very much for the help
 

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Be sure you dont have any vacuum leaks.How much vacuum do you have at idle? What power valve is in the carb. If you don't have enough vacuum to keep the power valve closed it is going to be rich no matter how much you adjust things.Also ignition has to be right before you can really adjust the carbureator.
 
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Ryanbrown36

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Be sure you dont have any vacuum leaks.How much vacuum do you have at idle? What power valve is in the carb. If you don't have enough vacuum to keep the power valve closed it is going to be rich no matter how much you adjust things.Also ignition has to be right before you can really adjust the carbureator.
I unfortunately don’t have a vacuum gauge right now but I will go get one. Not sure what power valve is in it, whatever comes stock in the carb. I believe ignition is about perfect now so that should be good.
 

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Is this a new carb or known good? Or no idea the condition?
Because if it’s a known good carb it will fire up with gas and vacuum.
Not even sure what it is at this point. You said it ran and now it doesn’t. What changed, you adjusting the carb?
Also if it’s a good carb, doesn’t matter what power valve it has in it for purposes of getting it to just run. PV doesn’t open until you’re cobbing on the throttle basically.
But if it doesn’t have vacuum keeping it closed at idle and part throttle or the engine has a vacuum leak somewhere it won’t idle.

Back to the oil and plugs. Yup plugs are black rich. Whatever. And the oil is probably fine. Don’t know what was done to the motor. Is it still in break in? Top and bottom end new? Flat tappet presume? Do you have break in oil in it? Have you broke in the cam if it has a new cam?
 

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Is this a new carb or known good? Or no idea the condition?
Because if it’s a known good carb it will fire up with gas and vacuum.
Not even sure what it is at this point. You said it ran and now it doesn’t. What changed, you adjusting the carb?
Also if it’s a good carb, doesn’t matter what power valve it has in it for purposes of getting it to just run. PV doesn’t open until you’re cobbing on the throttle basically.
But if it doesn’t have vacuum keeping it closed at idle and part throttle or the engine has a vacuum leak somewhere it won’t idle.

Back to the oil and plugs. Yup plugs are black rich. Whatever. And the oil is probably fine. Don’t know what was done to the motor. Is it still in break in? Top and bottom end new? Flat tappet presume? Do you have break in oil in it? Have you broke in the cam if it has a new cam?
it is a brand new, ran for about 20 mins totally when setting the timing. it did idle well with the timing set (idled a bit high and seemed rich) but didn't die. after flooding it I tried to take it for the first test drive the next day and set my accelerator pump and idle screw to base settings as they were off by quite a bit but didn't want to start but was also like -15 outside and most likely flooded it right off the start. then tried it the next day continuing to play with the carb, tried setting it back to what it was at before even though it shouldn't have any effect on starting and still nothing, cylinders were probably washed at this point and I obviously wasn't thinking. motor was ran by previous owner for a good break in period after he rebuilt it. has a mild build, sealed power hypereutectic flat tops, comp cams magnum cam, comp cams heavy duty roller rockers, lifters, valve springs, polished crank, all new main and rod bearing, rebuilt 882 heads, proformer rpm intake. was broken in and driven a couple times by the previous owner and then sat for a couple years, replaced all gaskets and stuff and then I bought it.
 

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Go back to basics. Spark, fuel, timing by TDC and rotor position. If all checks out try a new set of plugs. Also check for 12V on choke thermostat. When it runs again set timing, check advances, vacuum, and reset carb idle mix.

Of note, after an engine has been running rich, idle mix will need to be set a couple times until pre-existing fuel is burned off. Will lean out as fuel is burned.
 

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The way a power valve works is at low vacuum conditions( the farther you are in the throttle the lower your vacuum readings) so when you step on the throttle your vacuum drops and the power valve adds fuel. Now if you have a low vacuum condition because you have a manifold gasket leaking a base gasket leak,you've cranked the throttle stop screw in too many turns to try to bring the idle up.Now if you are idling at a vacuum level lower than your power valve rating,the power valve thinks you're accelerating and adds fuel. Not saying that's happening,just wanted to eliminate it. If you are pulling decent manifold vacuum at least above 11 the power valve won't open. It's one of the reasons I'm always harping on people with poor gas milage to check their vacuum advance,not enough timing and the carbs dumping more fuel because with the vacuum leak the carbureator thinks you are further in the throttle than you really are.
 
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