[the70OOJudge]

Hi everyone.... Took the Judge out this year and she runs fantastic till I push her at WOT and at around 4200 to 4500 She craps out like no gas....

I built the Original Ram Air III back in 1994, running around 425 hp, I put in a 69 fuel pump 5 years after that and rebuilt the carb... Its been running fantastic till now...

I did change the wires ( running 8mm ) with GM HEI this spring and figured it might be the new wires so went back to the old ones and its still there....???

I am using the original Ram AIr Carb and she idles and I can play up till 4200 and no problems... I am thinking its my pump? Getting old so I did order a new one from Ames .

[Dave M]

Maybe needle and seat too small? Does it feel like it's running out of gas?


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[the70OOJudge]

Yes, It feels like its running out of gas...

[Dave M]

Originally Posted by the70OOJudge

Yes, It feels like its running out of gas...

Sounds like the same problem that I had. Mine was doing it with different engines in the same car. Same carburetor too, which was rebuild by Cliff. I thought it was the filter, so I changed it. Didn't fix it. A friend told me to change the sock. Not only did I do that, but I changed the tank, sending unit, fuel lines, and pump. Still didn't fix it. So I called Cliff. He told me that I needed a bigger needle and seat. Because, the ethanol in the fuel. Engine burns the fuel faster. So I changed (going off memory here, which isn't very good) from a .125 to a .135. Haven't had the problem since.


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[the70OOJudge]

Originally Posted by Dave M

Sounds like the same problem that I had. Mine was doing it with different engines in the same car. Same carburetor too, which was rebuild by Cliff. I thought it was the filter, so I changed it. Didn't fix it. A friend told me to change the sock. Not only did I do that, but I changed the tank, sending unit, fuel lines, and pump. Still didn't fix it. So I called Cliff. He told me that I needed a bigger needle and seat. Because, the ethanol in the fuel. Engine burns the fuel faster. So I changed (going off memory here, which isn't very good) from a .125 to a .135. Haven't had the problem since.


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That could be part of it... I use 94 octane up here in Canada.. And Chevron says it has no ethanol but who can believe them now a days..... the only time I have ended up with a lower octane is when I head down to the States and the chevrons I get only have 92 octane and it apparently states it has ethanol.. I will check what size seats I have... I thought they were a .135 but my memory is like yours Thanks

[the70OOJudge]

Originally Posted by Dave M

Maybe needle and seat too small? Does it feel like it's running out of gas?


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It just started this year... it was good last year... same needle and seat from resto

[Formulajones]

Originally Posted by the70OOJudge

It just started this year... it was good last year... same needle and seat from resto

Sure sounds like a delivery issue. I'd rig a temporary cheap fuel pressure gauge taped to the windshield and go for a drive to confirm you're on the right track. If so, from there you'll have to start looking at the entire system. Check the rubber line connections at all the junctions for kinks, (tank to frame, frame to pump etc..) and even look inside the rubber lines to make sure they aren't deteriorated or collapsed. I've had the rubber lines that looked perfect on the outside, but deteriorated and looked like bubble gum inside, restricting fuel flow. If in doubt, just replace it.
Fuel sock is another area. More difficult to inspect as it requires pulling the tank, so I'd save that one for last after you've exhausted all other possibilities. Could be simple and just the pump getting weak. Not much to the fuel systems on these cars so should be pretty easy to narrow down.

[the70OOJudge]

Originally Posted by Formulajones

Sure sounds like a delivery issue. I'd rig a temporary cheap fuel pressure gauge taped to the windshield and go for a drive to confirm you're on the right track. If so, from there you'll have to start looking at the entire system. Check the rubber line connections at all the junctions for kinks, (tank to frame, frame to pump etc..) and even look inside the rubber lines to make sure they aren't deteriorated or collapsed. I've had the rubber lines that looked perfect on the outside, but deteriorated and looked like bubble gum inside, restricting fuel flow. If in doubt, just replace it.
Fuel sock is another area. More difficult to inspect as it requires pulling the tank, so I'd save that one for last after you've exhausted all other possibilities. Could be simple and just the pump getting weak. Not much to the fuel systems on these cars so should be pretty easy to narrow down.

Never thought of the rubber lines as they were changed back in 1994 or so .. keep forgetting I started the resto way back then... Maybe the ole goat and I should do another resto... just to tidy her up.. Thanks

[steve25]

Did this issue start from the get go when you took it out of hibernation?

[pfilean]

Fuel filter?? Had similar problem a while back and finally chased it to a fuel filter that I didn't think should be bad.

[the70OOJudge]

Originally Posted by pfilean

Fuel filter?? Had similar problem a while back and finally chased it to a fuel filter that I didn't think should be bad.

Changed the fuel filter in the carb.. Thats the only one I have..

[the70OOJudge]

Originally Posted by steve25

Did this issue start from the get go when you took it out of hibernation?

Yes , but I have run a couple tanks of gas through her and I had gas stabilizer in the tank.. Put it away October and had her out in April... Nice weather here lol

[Tom Vaught]

Are you starting to get Corn in your gas out in BC?

Sounds like the fuel sock might be fused up somewhat.

Tom V.

[the70OOJudge]

I changed the tank and sending unit 10 years or so ago,

[HO Kenny]

I had a weird similar problem but it started a little earlier in the rpms. A baffle in a muffler must have come come loose. It ran great as long as I didn't floor it. I unbolted the header flanges and my power came back. Lots of noise as well.

[steve25]

If the motor will rev up passed 4500 out of gear then it's 90 % certain you have a Carb / fuel delivery issue.
Does the Carbs secondary diaphragm work?

[the70OOJudge]

Originally Posted by steve25

If the motor will rev up passed 4500 out of gear then it's 90 % certain you have a Carb / fuel delivery issue.
Does the Carbs secondary diaphragm work?

I have not tried that yet... Good idea... Just did it under load.. Thanks

[the70OOJudge]

Originally Posted by steve25

If the motor will rev up passed 4500 out of gear then it's 90 % certain you have a Carb / fuel delivery issue.
Does the Carbs secondary diaphragm work?

Just tried and she will rev up pass 4500 rpm out of gear so it appears it is a carb / fuel delivery problem... How does a guy check the carbs secondary diaphram? That will be the vacume diaphram on the front left of the quadrajet?

[Joe's Garage]

That's a Holley carb 'thing'. Here's a pic of where they are located.

The 'accordion' rubber at the front left (driver's side) of your carb is a dust-boot over the accelerator pump. It's there to keep dirt out of the carburetor.

The secondary opening rate is controlled by a combination of your vacuum break and tension on the spring wound around the secondary air flap rod.

Good luck!

[Formulajones]

Originally Posted by the70OOJudge

Just tried and she will rev up pass 4500 rpm out of gear so it appears it is a carb / fuel delivery problem...

That most certainly sounds like a fuel delivery problem. Even with low fuel pressure or delivery issues, the engine will free rev no problem. It's when you put a load on the engine, with a long slow full throttle pull when fuel delivery issues appear. But that same car will sit still and crack the throttle all day long and sound fine.