Fuel filter
Thread Starter
Burning Brakes
Joined: Mar 2001
Posts: 1,203
Likes: 147
From: dalton ma
Fuel filter
I have the glass fuel filter on my 340 hp clone. Just back from a little cruise and the car is idling much slower than usual and not too smoothly either. The level of fuel in the filter is only about 1/4 inch. I've had this filter for 40 years and never noticed it before. What should the level of fuel be ? Is 1/4 " OK or should I be looking at a possible fuel pump replacement ? Thanks, Bob
Le Mans Master
Joined: Jan 2007
Posts: 6,004
Likes: 1,509
From: Prescott Arizona
I've seen those glass filters used before and even though you might see a portion of the filter filled with gas, they're still working correctly. Having said that, you're no doubt going to hear that any glass filter is probably a bad idea. Okay, lecture over, let's go back to your idle issue. Is this a new development, do you find it hesitate when you try to accelerate? Is the idle just low but still steady?
What's the condition of the ignition system, wires, cap, plugs, etc?
Mike T.
What's the condition of the ignition system, wires, cap, plugs, etc?
Mike T.
Tech Contributor
Joined: May 2005
Posts: 15,576
Likes: 118
From: Conroe Texas
As a point of reference, I'm in my garage right now with my '62 340 horse car idling at 750 RPM as indicated on the factory tach.
My fuel filter glass bowl is full. The filter element is a Fram paper filter, not the original stone element.
My fuel filter glass bowl is full. The filter element is a Fram paper filter, not the original stone element.
Le Mans Master
Joined: Jan 2007
Posts: 6,004
Likes: 1,509
From: Prescott Arizona
Jeff - I must have been reading too fast (uh-huh), I had visions of one of those glass filters with the threaded chrome end fittings, not an original glass filter from a '62. So, moving on...the stock 340 horse glass filter does fill up all the way and stays that way until the engine is turned off?
Mike T
Mike T
Tech Contributor
Joined: May 2005
Posts: 15,576
Likes: 118
From: Conroe Texas
Jeff - I must have been reading too fast (uh-huh), I had visions of one of those glass filters with the threaded chrome end fittings, not an original glass filter from a '62. So, moving on...the stock 340 horse glass filter does fill up all the way and stays that way until the engine is turned off?
Mike T
Mike T
Thread Starter
Burning Brakes
Joined: Mar 2001
Posts: 1,203
Likes: 147
From: dalton ma
Took another 20 mile test ride after dinner and all is well. Why it decided not to idle this PM is unknown. Engine is basic 340 specs with an AFB carb, Pertronix conversion, R45 plugs and has been running exceptionally well all spring. Only recent change was backing off the initial timing from 12* to 8* and appropriate carb adj.
Yeah, this is the filter with the stone thing in it. I would love to loosen the filter and purge some air but it's a bear to get sealed once it's disturbed.
Yeah, this is the filter with the stone thing in it. I would love to loosen the filter and purge some air but it's a bear to get sealed once it's disturbed.
Safety Car
Joined: May 2004
Posts: 4,469
Likes: 275
From: Naples FL
Paper is a better filter media than the stone. It's not a huge deal with carbs though. Just change the filter fairly often since ethanol acts as a fuel line cleaner.
Richard Newton
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Richard Newton
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