It's hooked up from valve cover to rear carb. Now functioning is probably another subject. Can't say that we have checked that yet for vacuum and functioning valve although it's all new.
Oil in Hemi's exhaust system
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Only dripping oil out of one manifold (so we hope only affecting one side) but car has H-pipe so smoke was coming out of both sides. But that's my top theory too.
The engine was built by a builder in OK and I don't remember his name. It was dyno tested and he picked it up with distributor timed, etc and put it straight into the car. The only work he did on it was trimming it out and re-jetting the carbs back to stock (not sure what carbs it was dyno'd with)). They are correct carbs for the engine. I suspect the rear carb float levels may be too high. He pulled the top off the front one because it was leaking at the primary shaft a little and it appeared to be set at shop manual spec of 7/32. He set it to 7/16 which seems to be current rebuild instructions we find. My 67 shop manual says 5/16. So a mystery that may relate to float size changes over the years. But other than the slight throttle shaft leak after shut down I didn't see anything about the carbs that would appear to be a big issue. But back to the tubes - I don't think he knows right now because I asked him first before I started pulling plug wires and it sounded like he had never pulled one before. So he is aware of the seals and I think that is one of the things on the list to check.
lewtot184
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those carbs probably came with the large brass float. 7/32" is correct. if fuel is pushing thru than the engine may have the high pressure pump. the high pressure pump needs the vapor separator.
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it won't work unless there is a breather (usually on the other valve cover) to let air in
Yes, there is a breather on the left valve cover - same system as my 440.
Our local, independent mechanic, builder, drivetrain rebuilder and just local all-around performance go-to guy is theorizing the problem is the front carb that had the high float settings and leaking throttle shafts. He thinks gas leaked down in the cylinders, pooled and fouled the plugs on startup and started pumping gas out the engine into the exhaust. He believes the gas sitting in the cylinders and going through the warm, sooty combustion chambers/manifolds gave it an oily appearance. But, he hasn't seen the car yet so don't know. Plan is to block off fuel to front secondary carb for now, pull the plugs and dry them, put a little oil in the cylinders, change the oil, turn the motor over, replace the plugs, start it and see what happens. Won't know until Sat. I'm all for starting with the simple stuff first.
Our local, independent mechanic, builder, drivetrain rebuilder and just local all-around performance go-to guy is theorizing the problem is the front carb that had the high float settings and leaking throttle shafts. He thinks gas leaked down in the cylinders, pooled and fouled the plugs on startup and started pumping gas out the engine into the exhaust. He believes the gas sitting in the cylinders and going through the warm, sooty combustion chambers/manifolds gave it an oily appearance. But, he hasn't seen the car yet so don't know. Plan is to block off fuel to front secondary carb for now, pull the plugs and dry them, put a little oil in the cylinders, change the oil, turn the motor over, replace the plugs, start it and see what happens. Won't know until Sat. I'm all for starting with the simple stuff first.
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Unless you smell gas in the oil or it seems real thin,I wouldn't change the oil.So if the carbs were real FAT they would sent up smoke signals.The oil leak could be a separate issue. The spark plug tubes will not leak if the plugs are tight.
After the carb is tuned the plugs might just clean themselves.If they are wet when they come out,you must determine if it gas or oil.When you pull the plugs,make sure the rubber in the socket is tight! Soon as the last thread comes out the plug has to be quickly or oil will get on the tip,,,,,,,,,then you can't get a proper look at the plugs.
After the carb is tuned the plugs might just clean themselves.If they are wet when they come out,you must determine if it gas or oil.When you pull the plugs,make sure the rubber in the socket is tight! Soon as the last thread comes out the plug has to be quickly or oil will get on the tip,,,,,,,,,then you can't get a proper look at the plugs.
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Must add,if you stand in front of the exhaust there is a difference between a fat carb and oil burn.Take a whiff and what do you SMELL?
It wasn't the smell that over-whelmed us but the smoke that came pouring out and filled his work space. I'm a bit doubtfull of the fuel theory too OldBee because what dripped out of the manifold connection was too thick where it puddled on the floor. But - I'm all for and understand eliminating the easy stuff first before starting engine disassembly. He's going to pull the plugs tomorrow and I hope to swing by and see what that reveals.
Thanks
Thanks
We had a much better day of things today and it looks like the motor doesn't have any serious issues. The plugs were very wet and fouled. He had put a big douse of CAM 2 fuel in the tank and apparently it doesn't evaporate like pump gas and leaves an oily-like residue for quite awhile. What was coming out of the exhaust manifold connection was gas run through the cylinders and exhaust. Some of the plus still had fuel completely spanning the electrode gap when pulled. The front carb has issues and leaks gas out of the left primary throttle shaft bore within about 60 seconds of shutting off the motor. Pulling it showed a wet gasket and lot of fuel in the intake. Cleaned the carb (did find some crap in it) and still leaked. Took if off and on 2 or 3 more times to lower the floats and examine things and still leaking fuel. So a friend is taking it to have the throttle shaft bushed.
But with the new plugs we ran the motor for quite some time and got it good and warm and after it finally burned all the fuel out of the cylinders and exhaust system and the smoke abated it was running like a champ. With the hydraulic roller it idles and sounds like a stock 383 or 440 HP - not much drama. But with rich jets (since changed) it dynoed at 505 HP with stock exhaust manifolds. Kind of a mystery why the builder didn't notice the leaky carb.
Always wanted to own a Hemi someday but after working on this one, it would have to be a manual brake car. That dang power booster and MC are a royal pain is the *** to work around.
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But with the new plugs we ran the motor for quite some time and got it good and warm and after it finally burned all the fuel out of the cylinders and exhaust system and the smoke abated it was running like a champ. With the hydraulic roller it idles and sounds like a stock 383 or 440 HP - not much drama. But with rich jets (since changed) it dynoed at 505 HP with stock exhaust manifolds. Kind of a mystery why the builder didn't notice the leaky carb.
Always wanted to own a Hemi someday but after working on this one, it would have to be a manual brake car. That dang power booster and MC are a royal pain is the *** to work around.
Thanks
Lol, now you see why me&a few others like manual steering&brakes. I always go for the easy stuff first, while in the back of mind——-
No, it's something else. We dropped the float levels several times to where there was not much more than about 1/2 inch of gas in the float chambers. Floats are good. Needle and seats are good. Engine ran cool - no sign of fuel from the boosters while running. Tops of throttle plates stayed dry while running. But about 60 seconds after shut down it would start dripping out off of the driver side throttle shaft. We even looked closely for a casting crack but can't find anything. It is a mystery how the fuel is getting down to the throttle shaft however with the engine off. It's obvious it's also dripping into the manifold off of the underside of the throttle shaft too. But the topside is dry - that's the mystery. Next easy step is bushing the throttle shaft so we'll see what that does.
Yes - he has oil and filter for a change on hand. Probably do before next start since this was a fuel problem and not an oil issue.
Thanks
Interesting, waiting for an answer.
Dye penetrate and remover.
Yeah - me too. I forgot to mention I stood over the running engine on a step stool staring down the carb with a flashlight looking for fuel. Fortunately no backfires. Can't figure how fuel from the fuel bowl can get to the throttle shaft except down the throat of the carb. Our mechanic buddy was mystified too - he really thought lowering the float levels would stop it. He took it back to his shop to study and get is bushed.
This is the front carb and I guess it doesn't have idle circuits since there are no idle mixture screws. Maybe there is some sort of transition circuit issue.
This is the front carb and I guess it doesn't have idle circuits since there are no idle mixture screws. Maybe there is some sort of transition circuit issue.
Could be a porous casting or a crack. I'd take it off and pull the top and pour gas into each bowl. In won't take but a few seconds to show up if there a problem.
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