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Old 03-14-2007, 11:19 AM
islandman islandman is offline
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carburetor leaking; fuel tank needs cleaning


O.K. guys, "replacement" of the parts is out due to a new cash flow problem!!!

So here's the problem:

First off is the Carburetor!!
It's the original stock 1 barrel Rochester BC model w/no manual choke. I rebuilt this Carb. less than a year ago and even though there were some minor problems (like stripped threads/lack of seal material,etc.), it has worked flawlessly until now!!

By the way, i fixed the minor problems w/Teflon tape and it seems to be holding up quite well!!

Now, the problem started when the car was out running around and it slowly sputtered then died! I was at home and it was my wife who was driving. She opened the hood and noticed that the in-line glass fuel filter was completely black!!! She didn't know what to do, so of course (on a cold & damp day), she took a screwdriver from the trunk's toolbox and tried tapping the fuel filter's "glass" sides to loosen the clogged screen. Well, i guess you can imagine what happened next?!! That's right, the glass shattered and now the car was not going anywhere!!! So anyways, the car was brought home and i checked it over. We desperately needed to get groceries across town and this is our only vehicle. So i removed the broken in-line fuel filter and put in a temporary (fuel resistant) hose. The hose is a clear plastic type used to siphon fuel. The 55 started right up, but i happened to notice while looking for leaks that more black contaminant's passed through the clear hose,& without a filter to stop it, they went straight into the fuel pump and then into the carb. There was a momentary "chug" and then the engine ran fine. The 55 ran good for about 2 weeks then the current problem happened. (i was in the hospital during this time so i couldn't replace the fuel filter!!).

So, now i get back home and check on the 55, it is still running and i'm about to replace that fuel filter when i noticed after the first 2-3 minutes of starting the car that a drop of fuel is coming from the top of the carb. Another minute later 2 drops, then 3 and so on.. until a spritz-like spray of fuel is dropping directly onto the hot exhaust manifold!!!! Well!!--that's not good!!! I have my wife start the car up again but this time with a blue shop towel slightly over the manifold to catch any gas!! I first saw the gas coming out from the throttle-linkage facing the driver, but upon closer inspection i saw fuel seemingly coming out from above the idle-arm & flowing down onto the linkage!! It looks like the fuel is coming out from the "Choke-shaft" end, where the idle-arm is connected to!!! (at the top of the carb.) I tried to tighten the connecting screw and all other possible loose parts but this did nothing!!! The 55 has sat still ever since! I was planning on replacing and upgrading the carb.but now that's not possible.

I'm no mechanic, but i have rebuilt this carb. before so my best guess is "contamination" causing some disturbance!! This seems odd to me though since when i rebuilt the carburetor last year, i found at least a full 1/4 cup of "rust powder/contaminants" inside the carburetor's fuel bowl and surrounding area's!!!!(this was before the fuel filter installation!!) Even with this Contamination the 55 Chevy's in-line 235.5 "blue flame" six motor ran o.k. (they built them good back then!!!) I would be really surprised to find that even fine rust powder could get past my fuel filter! The only time contaminants got past it was after it was accidentally broken by my wife and was replaced temporarily by a hose coupling! The fuel filter is located on the passenger side of the engine away from all heat sources and with nothing under it in case of leaks. This is a High Performance Fuel Filter that has a clear glass cylinder and a super fine micro-mesh that can be removed, cleaned and re-used!!!

That's why i think it would be weird if contamination is the problem.

In any case i guess my only way to go is to remove the carb. and inspect all passages and area's within, re-assemble and see if that does the trick!! Unless any of you guy's have a better solution or idea???????

I will take the top of the Carburetor off and check the float for leaks as well as blast air thru all passages and all surfaces!!! I'll then re-assemble the Carburetor and test for leaks!!!

By the way, I read a tip on leaking Carburetors and it said you should take a silicone gasket seal making material (like the type used in engine assembles!) and coat the Carburetor gasket on both sides with your finger. Let the gasket dry/set overnight and then install in your Carb. The tip say's any and all leaks around the gasket area's would be completely gone!!!

What do you think???? Should i try this as well????


Lastly, the "Fuel Tank"!!

I'll fix the fuel tank problem after the Carburetor's fixed. I know contaminants are coming from the tank, but when this High Performance Fuel Filter is on, it seems to capture everything!! I will keep a close eye on the filter and try and fix the Fuel Tank A.S.A.P.!! I need to have the 55 running to get it fixed (I.E. take to shop), as well as it's our only vehicle!!! I Still don't know how i'm going to get the tank clean while it's still attached to the car!! I can't afford to do the "radiator shop, flush and seal" idea or replace the tank at this time. So when i get to the tank how do i flush it?? Do i use diesel fuel or is there a better cleaner or a better way of solving my problem?

The cause of all my woes, because of all the info. above, it seems obvious that there's rust and who know's what else in there!!! The fuel gauge has not worked in years and the screen filter is missing off the fuel pick-up/sender!!!

So, how do i solve this problem?? I've tried taking the tank off but got stopped by the seized fill tube attached to the tank!! Again, replacement is out so how do i clean out the tank without removing it???

My thought is to:
Empty the tank, through a siphon hose. Remove the fuel pick-up/sending unit from the tank. Wash out interior (from filler tube?), with diesel fuel or other type of cleaner. Bad stuff comes out of pick-up/sender's mounting hole. Blast the empty tank and disconnected fuel lines with air compressor and re-assemble!!!

What do you think??? Is there a better way?? Could a shop clean out the tank with a pressure washer or some other method i'm not aware of??? Could i use water to wash out then flush with a type of cleaner then fuel?? I don't know?? Just trying to think outside the box!!!???

Any and all comments are gratefully accepted!!! If you can offer any idea's or suggestions PLEASE-PLEASE respond!!!!!!

Hoping for a solution.....
With the highest of hopes.........

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