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Discussion Starter #1 (Edited)
Hello all, I'm working on a 1977 Silver Wraith II project that is running extremely rich to the point of stalling. The exhaust is smoking so badly I look like a diesel pickup truck "rolling coal". I began by removing the dashpot/upper carburetor, which was heavily fouled with carbon and both were low on oil. The bores were extremely wet with gasoline with puddles of raw gasoline under the pistons. Servicing them made a marked improvement, but the car still smokes. The needles do not seem to be bent.

Talking with the previous owner he says the car ran well, but that the problems began after switching on the air conditioning. He then parked the car for several years. I am not sure if this could be connected.

My next step will be to remove the carbs entirely and set the float level. If setting the float level makes no difference I will assume the needle valves are bad. Is it correct that by 1977 the mixture and air screws are sealed and not meant to be adjusted? What else should be looked at?

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I have a 77 SSII. My car was running crazy rich. I removed the carbs and re-adjusted the mixture to factory... Seal caps were gone.. While I was there, I replaced all the vac hoses and now she runs smooth and now getting 12 mpg on 91 fuel. also, you may want to look into the timing while you are at it.
 

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Check your float valves. They may be gunked up.. then put some seafoam in the gas tank and run that out. That's what I would do.
Cheers, Phillip
 

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Did you confirm the choke is working properly and/or wire it in the off position?
Plastic floats can crack and fill with fuel which prevents them shutting off fuel when float bowl full. Viton tips on the needle valves can deteriorate. Turn on ignition to operate the fuel pump with dashpots and pistons/needles removed, does fuel spurt up from jet? If so the floats are sunk or Viton needle valve tips shot. Remove carbs to rectify. No fuel spurting up choke issue.
Unlikely the rich running condition has anything to do with the AC system.
 

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In the image below, the mixture adjustment screw tamper proof plug is missing exposing the slotted adjustment screw. If the plug is missing on your carbs someone may have adjusted the mixture screws to provide an overly rich mixture. If you cannot see the slotted screw, and the tamper proof plug is still intact, it is very likely the mixture setting is correct so don't remove the plug and start fiddling with it.

HIF 2.JPG
 
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