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Fuel problem symptoms

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01-24-2005, 07:04 PM
Danny Z
Fuel problem symptoms
After reading ron's post and the responses I have a question regarding the mentioned symptoms of a clogged or dirty filter. I've noticed on occasion after running for a bunch of miles the 454 will cut out when I get my foot into it. It just lasts a second or two and a little feathering of the pedal brings it right back to life. Does this sound like the symptoms you are talking about? Or does this sound more like a fuel pump?

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Dan & Suzy Z
'81 Euro 28
01-24-2005, 07:43 PM
DALE SMITH
I would say the carb might need alittle attention. I wouldn't think a fuel pump would act as such. I can't see the fuel pump coming to life because you touched the pedal a tad. I will read with interest what others say. Dale
01-24-2005, 11:00 PM
ron
Hmmmmm, accelerator pump?
01-24-2005, 11:50 PM
Skiman
Perhaps a bit of moisture in the system? Have you tried some methyl hydrate(gas line antifreeze)
01-25-2005, 01:44 AM
Gunner
"after running for a bunch of miles the 454 will cut out when I get my foot into it..."

Are you running steadily at high rpm and it chokes OR are you running at moderate rpm and it stumbles when you step down hard? Quadrajets (which I presume you have) will bog down if the huge secondaries are opened suddenly at relatively low rpm.
If you are running steadily at high rpm for a while the carb may be using more than the pump can supply, esp if it is a mechanical (not electrical) pump sucking 25+ feet through two flters.
1) Change the in-line filter on the frame rail -don't put it on backward!
2) As above: check for fuel line leak.
3) Visually check to see if your fuel pump is leaking (run your finger over it).
4) As above: check accelerator pump
5) Finally: Quadrajets are notorious for the throttle plate shaft to wear a hole in the body where it pivots; if so, it will suck air and mess up the mixture and it is a random occurence.

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"You are what you drive" - Clint Eastwood



[This message has been edited by Gunner (edited January 24, 2005).]
01-25-2005, 09:14 AM
Danny Z
Gunner. The first time I noyiced it was getting into the hills in Bama, running about 55. Going up a hill would mean using more right toe and this is when it would cough. I may have kicked in the 4 bbl but I didn't think so. Back in Fla., when I run Interstate for a while, then get off and start away from a stop sign, it cuts out momentarily, but as I said, a little toe tappin' brings her right back. Thanks for the directions and I'll start in on them right after work today.

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Dan & Suzy Z
'81 Euro 28
01-25-2005, 03:05 PM
Gunner
MORE: The wife complains that at oh-dark-thirty this morning I woke her by exclaiming loudly; when she said What? I replied "Distributor Module". I have no memory of the conversation but I do have memories of (more than one) "distributor modules" gone bad. This is a plug-in device in the distributor in 70s-80s "Electronic ignition" Chevys. When it starts going bad it will stop spark to the plugs for short periods, then long periods; the engine will stumble, or die and often restart immediately. If you're cruising it may cough or stop and restart by itself if the lack of spark is short enough.
Anyhow, keep this in mind.

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"You are what you drive" - Clint Eastwood
01-25-2005, 06:15 PM
Danny Z
I had a module go south in my 76 Gran Prix, but I don't remember any warning. It was under the rotor and very easy to raplace, so I'll just drop one in while I'm in the doghouse and eliminate another possible villain. Thanks.

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Dan & Suzy Z
'81 Euro 28
01-26-2005, 02:11 AM
ccctimtation
I had changed my point system to Pertronix electronic ignition. I had a failure and have gone back to points but the failure was not easy to discover at first. I had run for about an hour or more around 2750 rpm and pushed the throttles to the wall. The port engine stumbled, a little miss, then took off and was fine. After shut down it was tough to restart. I ended up finding a shift or mistake in timing. I retimed the distributor and had no problems until the next time I decided to make the cruiser a gofast boat. Same problem. Timing will drop 5 to 15 degrees from setting depending on temperature, phase of the moon, distance from safe anchorage etc.
This may not be your problem but it would be a good thing to try a change of the module. If that is not the problem having one on board is still a good idea.
Best luck,
Tim
1968 35' CC Commander
01-26-2005, 06:54 PM
Danny Z
One advantage to fresh water boating, you can talk about your 68 Chris in the present tense! Thanx for the tip.

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Dan & Suzy Z
'81 Euro 28
01-26-2005, 09:25 PM
Ed Chevalier
I've had the same problem with a bad fuel pump. It would stumble and die and it would come back to life after a few seconds. The only sure way to check the pump is with a inline fuel pressure gauge(around $25 from Summit Racing or Jeg's). I installed a gauge to verify that the pump was bad (0 psi). You can temporarily install the gauge and remove after testing (safest method). Rubber fuel line should only be used for testing. After the new pump was installed pressure was up to 5 psi.