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  #1  
Old September 29th, 2016, 10:18 PM
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Exclamation The saga continues - Sputtering, loss of power when accelerating

Driving along this morning and everything was fine. All of a sudden it starts sputtering when I accelerate and I'm not getting enough power.

It's had all new plugs, points, tuning etc.....

However, I've put an inline fuel filter before the carb and that has some crap in it. Not a huge amount (I once owned a straight 6 Fairmont that would run like a champ right up until the filter was chock full), so I wouldn't have thought that would be the cause?

Naturally this has happened the day I decide to take it to work. So now I'm here all day being paranoid that I'm going to cause damage trying to nurse it home. Or that it's not going to make it.
Oh, it's a 61 305D if that's relevant at all. And yes, it has petrol (although at the moment I am having to use a broom handle to determine that).
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Old September 29th, 2016, 11:43 PM
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Default Re: The saga continues - Sputtering, loss of power when accelerating

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Originally Posted by Jmclendon View Post
Driving along this morning and everything was fine. All of a sudden it starts sputtering when I accelerate and I'm not getting enough power.

It's had all new plugs, points, tuning etc.....

However, I've put an inline fuel filter before the carb and that has some crap in it. Not a huge amount (I once owned a straight 6 Fairmont that would run like a champ right up until the filter was chock full), so I wouldn't have thought that would be the cause?

Naturally this has happened the day I decide to take it to work. So now I'm here all day being paranoid that I'm going to cause damage trying to nurse it home. Or that it's not going to make it.
Oh, it's a 61 305D if that's relevant at all. And yes, it has petrol (although at the moment I am having to use a broom handle to determine that).
There's a hidden filter under the passenger side cab. It looks like a soda can sticking down. The replacement part is Wix 33271. Swap that puppy out and see if it clears up. Oh, and gas runs ALL DOWN your arm when you unscrew that can.
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Old September 29th, 2016, 11:49 PM
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Default Re: The saga continues - Sputtering, loss of power when accelerating

Is it re-useable? I guess what I'm wondering is if I take it off and give it a fling out (hopefully removing the crap that's in it, if that's the problem) will I be able to just pop it back in?

This is just so I can get it home of course. I'd be getting a replacement first chance I get.

Also, when you say the gas runs down you're arm, does that mean it's going to just keep spewing out of the tank until I put it back in? Or is it just going to be whatever amount of gas that's currently sitting in the filter?

Fingers crossed it's something this simple. I'd be pretty devastated if it was something catastrophic.
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Old September 30th, 2016, 01:47 AM
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Default Re: The saga continues - Sputtering, loss of power when accelerating

Just went through this. Ended up being that the sending unit did not have the screen on it allowing a ton of crap through the line and into the primary filter. And with an electric pump you know something is wrong Right away. New sending unit, 2 new filters, blew out the lines and for the 1st time I am actually seeing 10 psi cold.
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Old September 30th, 2016, 02:01 AM
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Default Re: The saga continues - Sputtering, loss of power when accelerating

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Just went through this. Ended up being that the sending unit did not have the screen on it allowing a ton of crap through the line and into the primary filter. And with an electric pump you know something is wrong Right away. New sending unit, 2 new filters, blew out the lines and for the 1st time I am actually seeing 10 psi cold.
That all sounds much better than what my worst case scenario brain was thinking. Typical of me, my first thought was a dying engine.

I'm really hoping it's something basic..... There is some crap in the pre-carb filter, and pretty much the only mod-con that the truck has (other than seatbelts) is an electric fuel pump.

I've already got a new sending unit on order (as much as I don't mind checking the level with a stick, it's not something I want to keep doing).

So, fingers crossed? Is there a chance it could be something major? If so, what other symptoms should I be looking for?
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Old September 30th, 2016, 02:04 AM
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Default Re: The saga continues - Sputtering, loss of power when accelerating

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Originally Posted by Jmclendon View Post
That all sounds much better than what my worst case scenario brain was thinking. Typical of me, my first thought was a dying engine.

I'm really hoping it's something basic..... There is some crap in the pre-carb filter, and pretty much the only mod-con that the truck has (other than seatbelts) is an electric fuel pump.

I've already got a new sending unit on order (as much as I don't mind checking the level with a stick, it's not something I want to keep doing).

So, fingers crossed? Is there a chance it could be something major? If so, what other symptoms should I be looking for?
If your driving along and it just suddenly starts to spit and sputter is normally two things...fuel or ignition. In this case all your ignition components are new so there's a 99.99% chance they are fine. The fuel system however I don't recall you checking? If some crap got to the second filter I am sure the 1st is packed. That's how it was with mine. By the way, be sure to disconnect the metal line from the send unit at the tank...that helps keep the fuel from siphoning and emptying the tank when you pull a line off from underneath. lol
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Old September 30th, 2016, 02:27 AM
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Default Re: The saga continues - Sputtering, loss of power when accelerating

I had an old Fairmont before with a badly rusted fuel tank. Consequently, I had to carry a tank of compressed air in the back seat so that when the sock in the tank filled with rust I could pull the line off the pump and blow air back through the fuel system (which blew the rust off the sock) and then suck petrol back up the line, reattach it to the fuel pump and keep going.

For the short term (IE getting me home today) could I do something similar as a test? I don't have a tank of compressed air, but I'm thinking if I blow into the fuel line really hard I might be able to lung it? Except I'm assuming since this is an electric fuel pump I won't have to suck petrol back up the line afterwards?

Also, there's a shutoff valve on the petrol tank. Presumably if I close it then that should keep the tank from emptying when I pull a line off?

I know some of these are going to be 'duh' questions, I'm just well aware of my own limitations when it comes to experience and whatnot, so I'd rather ask a dumb question than assume that I know what I'm talking about and make a dumb mistake.
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Old September 30th, 2016, 05:43 AM
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Default Re: The saga continues - Sputtering, loss of power when accelerating

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Originally Posted by Jmclendon View Post
I had an old Fairmont before with a badly rusted fuel tank. Consequently, I had to carry a tank of compressed air in the back seat so that when the sock in the tank filled with rust I could pull the line off the pump and blow air back through the fuel system (which blew the rust off the sock) and then suck petrol back up the line, reattach it to the fuel pump and keep going.

For the short term (IE getting me home today) could I do something similar as a test? I don't have a tank of compressed air, but I'm thinking if I blow into the fuel line really hard I might be able to lung it? Except I'm assuming since this is an electric fuel pump I won't have to suck petrol back up the line afterwards?

Also, there's a shutoff valve on the petrol tank. Presumably if I close it then that should keep the tank from emptying when I pull a line off?

I know some of these are going to be 'duh' questions, I'm just well aware of my own limitations when it comes to experience and whatnot, so I'd rather ask a dumb question than assume that I know what I'm talking about and make a dumb mistake.
You won't be able to blow hard enough. haha I'd just cruise it home and on the weekend take the time to fix it, so that way you can Find the possible problem and know you've fixed it. When mine had issues it happened at the worst possible time...leading me to think it was one of a million issues. When my engine lost power I was pulling a hill at 57 mph on a 105 degree day. Lost power and thought it had eaten rings. Looked through the mirrors for smoke and saw nothing...next thought was ignition or fuel...limped to the top and pulled over. Idled perfect....took a non load throttle fine....but you could grab the filter and feel the fuel pulsing really bad. I thought it was boiling, but it was really pulsing because of the clogged filter BEHIND the pump. That's the issue...Pumps are made to Pump...not Pull. The pump was having such a hard time Pulling that it couldn't keep up with the needs of the motor at speeds above 45 or under hard acceleration. Thus making me think things were worse than they were. So I decided to redo the Whole system starting with filters....and there it was...a jam packed filter behind the pump. Lucky I didn't fry the pump. I them completely removed the sending unit from the tank and saw there was no pickup screen....replaced it with a new one I had already() and cleaned out the lines. Went ahead and installed a USA made pump in with two fresh filters one in behind and one in front of the carb for more cheap insurance. And am now running at 10 PSI cold and 6 PSI hot and happy. I need to regulate it down to 5 as eddys hate high pressure but no issues yet.

Unless you have all the tools you need, I'd limp home and wait until the weekend to do any work.
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Old September 30th, 2016, 06:48 AM
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Default Re: The saga continues - Sputtering, loss of power when accelerating

Hello All,
Quick one as I'm on a phone. I nursed him home!

Fingers crossed this weekend is a productive one lol
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Old September 30th, 2016, 06:37 PM
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Default Re: The saga continues - Sputtering, loss of power when accelerating

My 64 suburban did not have a filter between the tank and the fuel pump, so all the crap filled up the fuel pump. took the pump a part cleaned it out. put a filter on the tank side of the pump. In the end, I took off the fuel tank, pressure washed the inside,used muratic acid to clean, lined it with red coat. Tanks that are real bad throw a chunk of chain in it and shake it. The best redneck way is to fill with some gravel, strap it to a tractor tire, and go for a drive.
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