Fuel Starvation?
Thread Starter
Burning Brakes
Joined: May 2007
Posts: 1,042
Likes: 1
From: Greensboro NC
Fuel Starvation?
Wierd stuff going on.
Driving home today the car starts just dying.
Tach is at about 3200 (65 or so, 355 rears) when it drops out then comes back part way up, drops out again and again until it dies.
I coast about 1/4 mile, bumpstart in 3rd, and it comes back strong for about 1/2 mile or so, then does the same thing all over.
Luckily I managed to nurse it back home.
The guy I bought it from says it did something similar a couple weeks back and he found a bad diaphram in the fuel pump, replaced it and all was good.
I guess his Bubba work didn't hold up?
Anyway...
The car was a 350 hp, 350 cu, 380 lbs ft torque, 11:1 comp ratio that had a GM 190 hp, 350 cu installed in 1990...
It has a electric pump in back going to the mechanical pump in front (non-stock chrome job), no fuel filter, and the return line is blocked off.
My thoughts are to bypass the mechanical pump and install a pressure regulator.
So:
Does it need a block off plate on the old pump?
Currently a Qjet, so what should the pressure be set at?
What's a good looking inline filter that I can mount up front?
Driving home today the car starts just dying.
Tach is at about 3200 (65 or so, 355 rears) when it drops out then comes back part way up, drops out again and again until it dies.
I coast about 1/4 mile, bumpstart in 3rd, and it comes back strong for about 1/2 mile or so, then does the same thing all over.
Luckily I managed to nurse it back home.
The guy I bought it from says it did something similar a couple weeks back and he found a bad diaphram in the fuel pump, replaced it and all was good.
I guess his Bubba work didn't hold up?
Anyway...
The car was a 350 hp, 350 cu, 380 lbs ft torque, 11:1 comp ratio that had a GM 190 hp, 350 cu installed in 1990...
It has a electric pump in back going to the mechanical pump in front (non-stock chrome job), no fuel filter, and the return line is blocked off.
My thoughts are to bypass the mechanical pump and install a pressure regulator.
So:
Does it need a block off plate on the old pump?
Currently a Qjet, so what should the pressure be set at?
What's a good looking inline filter that I can mount up front?
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
I think I would be looking to losing the electric, put in a correct mechanical and a filter in the carb body like it is supposed to be, Q-jet fuel pressure is on the order of 5 or 7 lbs I think
Melting Slicks
Joined: Mar 2006
Posts: 3,342
Likes: 7
From: Connecticut
Your going to have to get in there to remove the old mechanical pump anyhow so why not make it correct.
Thread Starter
Burning Brakes
Joined: May 2007
Posts: 1,042
Likes: 1
From: Greensboro NC
Well, I like the electric pump....
Have one on my 65 Mustang and it cured a lot of ills.
Main thing I'm concerned with is having the pressure too high for the old Qjet before the Qjet gets replaced with 650 Holley dbl pumper (friend is giving me one)....
The other thing I really need to do is change something with regards the high RPM's at highway speeds. 3500 at 65mph is a tad more than it needs to be...
Have one on my 65 Mustang and it cured a lot of ills.
Main thing I'm concerned with is having the pressure too high for the old Qjet before the Qjet gets replaced with 650 Holley dbl pumper (friend is giving me one)....
The other thing I really need to do is change something with regards the high RPM's at highway speeds. 3500 at 65mph is a tad more than it needs to be...
Melting Slicks
Joined: Mar 2006
Posts: 3,342
Likes: 7
From: Connecticut
I am running the 3.08:1 and cruise at 70 mph @ 2,600 rpm but its a bit depressing off the start to say the least.
ToolMan
Joined: Mar 2006
Posts: 71
Likes: 0
From: Magnolia Texas
Your problem sounds like a fuel delivery problem. Any system you have should have a fuel filter in the line or at the carb.
If there is a filter, it could be clogged or the sock in your gas tank pickup could be degrading. Look into your tank to see it.
If you stay with an electric pump, remove the mechanical pump and put a block out plate on. Check out Summit for a pressure regulator, filter and gauge. Set the pressure to 5-6.
Good luck, Rob
If there is a filter, it could be clogged or the sock in your gas tank pickup could be degrading. Look into your tank to see it.
If you stay with an electric pump, remove the mechanical pump and put a block out plate on. Check out Summit for a pressure regulator, filter and gauge. Set the pressure to 5-6.
Good luck, Rob
Melting Slicks
Joined: Feb 2002
Posts: 2,625
Likes: 0
From: Cut n Shoot TX
I had a problem similar to this. Turned out to be a kink that had formed in the fuel line rubber hose where the steel lines to the tank transitioned to the steel line running to the carb....
Thread Starter
Burning Brakes
Joined: May 2007
Posts: 1,042
Likes: 1
From: Greensboro NC
Thanks.
FWIW:
I checked Summit and a couple others.
The Mr Gasket adjustable pressure regulator and block off plate were cheaper at http://www.partsamerica.com than Summit, Jegs and others.
I also priced the Energy Suspension control arm bushing sets. Again partsamerica was the cheapest.
And I can pick the parts up at a local Advance Auto Parts.
Seems like a no brainer....
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