Opinion
Thread Starter
Instructor
Joined: Sep 2006
Posts: 141
Likes: 0
From: Encinitas Ca
Opinion
I would like an opinion from the carb experts. Subject: 1970 350/350 with a Quadrajet. Everything is stock. I had the carb rebuilt by a local expert. First time the carb worked fine at start up for a week then when I would go to start again gas not only would flood the engine but would pour all over the outside as well. I took it back and he found a little old screening from the old pickup in the old tank. Now has a new tank and pickup. It has been fine now for two months and yesterday it happened again. Some of the worst flooding I have ever seen, engine won't start for an hour and gas all over the top of the engine pouring down the side. The carb man is good for the garantee but this is getting old. When the engine is running it is perfect and has excellent response. And yes the filter is in place. Opinion please. Mike.
Race Director
Joined: Feb 2005
Posts: 16,100
Likes: 17
Very possible original source, particles (old screening) still in fuel lines....I'd blow out lines,carb,change fuel filters....does not take much to foul needle/seat...
Note:this happened to me when I bought a new Roadrunner...twice..dealer finally found weld slag in tank...very small particles got in lines from tank...they had to clean tank/lines,etc..
Rich
Note:this happened to me when I bought a new Roadrunner...twice..dealer finally found weld slag in tank...very small particles got in lines from tank...they had to clean tank/lines,etc..
Rich
Last edited by rihwoods; Apr 9, 2007 at 09:41 AM.
Team Owner
Joined: Feb 2005
Posts: 32,519
Likes: 1
From: central America
St. Jude Donor '08-'09
Did you pull off the line and see anything stuck by the fuel filter?
with rihwoods.
I would start by blowing out all the lines if you didn't see anything in there.
You could try pulling off the line to the carb and emptying it into a pail.
Easier to check for debris.
trw
with rihwoods.I would start by blowing out all the lines if you didn't see anything in there.
You could try pulling off the line to the carb and emptying it into a pail.
Easier to check for debris.
trw
Burning Brakes
Joined: Oct 2004
Posts: 920
Likes: 1
From: Shelby Township Michigan
Very interesting problem. Based on my own rebuild experience, I would bet that the needle is not seating. This would allow a tremendous amount of fuel to flood the carburetor. The float could be stuck in the lowered position (I am not sure how this would happen). I would bet that fueld is pouring throught the accelerator pump and to the outside of the carb.
Best bet would be to take the carb back for diagnosis or another rebuild.
Good luck,
Dino
Best bet would be to take the carb back for diagnosis or another rebuild.
Good luck,
Dino
Race Director
Joined: Feb 2005
Posts: 16,100
Likes: 17
Race Director
Joined: Feb 2005
Posts: 16,100
Likes: 17
Very interesting problem. Based on my own rebuild experience, I would bet that the needle is not seating. This would allow a tremendous amount of fuel to flood the carburetor. The float could be stuck in the lowered position (I am not sure how this would happen). I would bet that fueld is pouring throught the accelerator pump and to the outside of the carb.
Best bet would be to take the carb back for diagnosis or another rebuild.
Good luck,
Dino
Best bet would be to take the carb back for diagnosis or another rebuild.
Good luck,
Dino
Thread Starter
Instructor
Joined: Sep 2006
Posts: 141
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From: Encinitas Ca
Reporting Back on '70 350
Well, I unscrewed the fuel line. To bad I can't unscrew all of my screwups. Anyway, I looked at the filter, clean, so I placed it back in its little area and screwed in the fuel line, got in the car and with one push of the gas pedal to ingage the choke the car fired right up. No fuel pouring out. Holy Moly, whats going on? Its like it never happened. Well thats a lie, it happened two months ago but I meant recently. If it happens again I guess it will need to go back to Mr Carb and having fix it. Thanks for all of the input. Rich, I like your car
Last edited by mikebaskette; Apr 9, 2007 at 07:55 PM.
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Safety Car
Joined: Sep 2005
Posts: 4,215
Likes: 643
From: Orange County Ca
I had a bad float. One of the plastic ones, swelled up after about 2 months, and would rub against the inside of the carb. Mine stuck in the closed position so no gas would come in, but I guess it could get stuck open as well. Intermitent problems with new parts really suck, because you don't always check a new part. With a decent filter, I don't think any problem with the tank or lines would cause flooding. Has to be somthing with the needle valve, float, fuel pressure, etc.
Race Director
Joined: Feb 2005
Posts: 16,100
Likes: 17
Well, I unscrewed the fuel line. To bad I can't unscrew all of my screwups. Anyway, I looked at the filter, clean, so I placed it back in its little area and screwed in the fuel line, got in the car and with one push of the gas pedal to ingage the choke the car fired right up. No fuel pouring out. Holy Moly, whats going on? Its like it never happened. Well thats a lie, it happened two months ago but I meant recently. If it happens again I guess it will need to go back to Mr Carb and having fix it. Thanks for all of the input. Rich, I like your car
Jump in on one of runs sometime..
We post in the SOCAL regional events section...Corvette/Cobra GTG's...Rich
Thread Starter
Instructor
Joined: Sep 2006
Posts: 141
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From: Encinitas Ca
It happend
It happened again this morning, flooded so bad the car would not run. Soooo off to the carb guy....again. He did mention the issue of new parts turning to mush inside the carb. I took in another carb as well so we will see how this works (secondaries were not opening). I need that guteral sound from the secondaries, brings out my primal side. While I was there he removed the filter and nothing after cutting it open. I will report back the findings. Until then.
Le Mans Master
Joined: Jan 2007
Posts: 5,485
Likes: 7
From: Peekskill NY
I just went through the issue of secondaries not opening. After a lot of great feedback from forum members, it ended up being the most simple adjustment of all. The primary tang was just kissing the secondary lever tang and when I SLOWLY started to bend the tangs to make contact, I did this untill the secondary opened just about verticle. What a major difference.
Glenn
Glenn
Drifting
Joined: May 2006
Posts: 1,480
Likes: 2
From: Circleville Ohio
Vader vette
I had A 305 pick up truck that would do the same thing gas all of the sudden I would stop Take the top off of the carb off take out the Jets
blow them out put them back in and it would work great untill they clogged up again.Drop that carb guy.
blow them out put them back in and it would work great untill they clogged up again.Drop that carb guy.
Thread Starter
Instructor
Joined: Sep 2006
Posts: 141
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From: Encinitas Ca
I'm Back!
Got the carb back from Mr. Carb guy. Had him do another one for me while the first was being looked at. I will try and make this short. While in conversation I purchased two new gaskets (thick) for both cars and he agreed that it would not be a bad idea to replace both as they get hard/brittle. Just for grins I placed the other carb on the fuel belching car.....same thing happend, fuel everywhere. Now what are the chances? I removed the carb and looked at the old thick gasket, it was not flat. The gasket appears to have been made for a different style Quadrajet, it had gentle lumps in the design. This is one heck of a lesson for me. I then placed the new FLAT gasket on the manifold and attached the carb. The poor engine was so flooded it took a while to fire. Unfriggin real! Now the car fires first crank, no more grinding to get it going. No flooding.....perfect. Summation: air was being drawn below the carb base. Now I can't figure why so much fuel was everywhere but now I don't care. The best issue now is how quick the little 350 can be. I will be changing the gasket on the coupe cuz' I know that it should be faster than it is now. Thanks for all of your input and until my next crissis, solong
Thread Starter
Instructor
Joined: Sep 2006
Posts: 141
Likes: 0
From: Encinitas Ca
A return to my "HELL"
My car has been starting and running perfect until I went to start it this morning, flooding all over the engine.....again.
Tried my carb off of the other '70, it did the same thing, flooded all over the same engine. So now I will install a new fuel pump, the existing one looks stock but I will replace it anyway. After that I have run out of ideas. The subject car has a new gas tank and sending unit, cleaned fuel lines and the filter shows nothing as everything is clean. What in the heck causes two different carbs to flood out and over the top and soak the intake so bad the car will not start?
Tried my carb off of the other '70, it did the same thing, flooded all over the same engine. So now I will install a new fuel pump, the existing one looks stock but I will replace it anyway. After that I have run out of ideas. The subject car has a new gas tank and sending unit, cleaned fuel lines and the filter shows nothing as everything is clean. What in the heck causes two different carbs to flood out and over the top and soak the intake so bad the car will not start?