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fe427avanti
11-18-2006, 09:39 PM
I bought a 63 Avanti that didnt run. Changed the auto to manual, Replaced the distributor with an electronic uint by Dave Thiebuild along with the carb. Replaced many other parts as well. I am having a problem tuning the car. Starts well, idles good, but seems like its getting too much fuel. I have made sure the needle is not blocked, but dont really know what else the problem could be. When I exchanged the carb, Dave said the carb I had wasn't for an Avanti. This is my first Studebaker so I dont have any info about the engine codes. Could an Avanti carb on a non avanti 289 be this much of a problem? The # stamped on the block is PH329.

StudeRich
11-18-2006, 11:22 PM
The whole ENGINE is non-Avanti, so IF it is actually Std. 289 inside, it should not matter! The block at least, is a 1964 Standard 289 from a Lark or Hawk. You may have a fuel pump problem, a wrong fuel pump or bubble in the diaphram can actually cause too much pressure.

StudeRich
Studebakers Northwest
Ferndale, WA

Dick Steinkamp
11-19-2006, 12:35 AM
quote:Originally posted by fe427avanti
but seems like its getting too much fuel.


What are the symptoms?

http://static.flickr.com/100/292046667_cc1661ba0e_m.jpg

fe427avanti
11-19-2006, 01:02 PM
quote:Originally posted by Dick Steinkamp


quote:Originally posted by fe427avanti
but seems like its getting too much fuel.


What are the symptoms?

http://static.flickr.com/100/292046667_cc1661ba0e_m.jpg


has a hard time on acceleration. most of the time, seems to flood out.
possible back fire but sounds more like raw fuel igniting in the exhaust. leaks fuel from exhaust.

Dick Steinkamp
11-19-2006, 01:54 PM
quote:Originally posted by fe427avanti

has a hard time on acceleration. most of the time, seems to flood out.
possible back fire but sounds more like raw fuel igniting in the exhaust. leaks fuel from exhaust.



Fuel really can't "leak from the exhaust". My guess is that what you are seeing here is condensation (water). All cars do this to some extent on start up. It's normal. If it was fuel, your car would be on fire [:0].

Poping either back through the carb (can you see flames coming out of the carb with the air cleaner off?) or through the exhaust, can be caused by wrong ignition timing (usual cause), but also by cam timing off, or stuck valves. Also by fouled plugs, loose wire in the ignition circuit (primary or secondary), or by a too rich or too lean mixture.

What do you mean by "hard time on acceleration"? Does it stumble when you press the accelerator? Only when it's cold? If so, it could be the choke isn't working properly. If when hot it could be that the carb accelerator pump isn't working properly or the timing is off. Or do you mean it doesn't have much power when accelerating but it doesn't stumble? If so, it could be the carb needs reabuilding or adjustment, timing off, distributor advance not working, valves adjusted wrong, and probably many other possibilities.

Again, what do you mean by "seems to flood out"? This is a diagnosis, not a symptom. Does the engine "die" when you open the throttle? With the engine not running can you look down the throat of the carb and see gas squirting when you work the accelerator? Do you get black smoke out of the exhaust at any time? Under what conditions? Have you adjusted the timing, dwell, and valves per the shop manual? Have you tested the mechanical and vacuum advance mechanisms in the distributor to see if they are working?

Stick with it, you'll woop it :)

http://static.flickr.com/100/292046667_cc1661ba0e_m.jpg

John Kirchhoff
11-19-2006, 07:10 PM
Often times a too rich mixture runs better when the engine is cold than after it warms up and too lean runs better after it's warmed than when it's cold.

Lean mixtures tend to backfire through the exhaust on decceleration.

A too rich mixture tends to run better the faster the engine runs or under a heavy load. A too lean mixture runs better on a light load.

A too rich mixture tends to make the engine lope or have a "soft" quality to the misfires. A too lean mixture makes an engine buck and the misfires are sharp or abrupt.

Help any?

Roscomacaw
11-20-2006, 12:17 AM
IF.... your diagnosis in correct (getting TOO MUCH fuel) then Stude Rich's idea of too much pressure could be at fault. Is this car using the factory (mechanical) fuel pump or an electric? Electrics have a tendancy to put out more pressure than the carb can handle. This might dictate a pressure regulator to stop the fuel pump from overpowering the float needle.
Of course, a carb improperly jetted would cause richness as well, but if I read right, you have a carb from Dave as well? I doubt Dave would get it wrong - the jetting, that is.[:I]

Miscreant adrift in
the BerStuda Triangle!!

1957 Transtar 1/2ton
1960 Larkvertible V8
1958 Provincial wagon
1953 Commander coupe

StudeRich
11-20-2006, 01:19 AM
My idea could be at fault?[:0] I think you do mean the excess fuel pressure could be at fault, [}:)]Right? :D:DLOL


quote:Originally posted by Mr.Biggs

IF.... your diagnosis in correct (getting TOO MUCH fuel) then Stude Rich's idea of too much pressure could be at fault.

StudeRich
Studebakers Northwest
Ferndale, WA

Roscomacaw
11-20-2006, 01:30 AM
Insert "THE" for "at", Rich.[:I] Really - I wasn't trying to blame YOU.[B)]

Miscreant adrift in
the BerStuda Triangle!!

1957 Transtar 1/2ton
1960 Larkvertible V8
1958 Provincial wagon
1953 Commander coupe

sbca96
11-20-2006, 01:38 AM
You can get an adjustible fuel pressure regulator from any auto parts
house and add it between the fuel pump and carb. Set it to 3 psi and
see if the problem goes away. There isnt much different between an
Avanti carb and a non-Avanti Carb. Just jetting, and its not a big
enough difference to cause a serious problem.

Tom

'63 Avanti, zinc plated drilled & slotted 03 Mustang Cobra 13" front disc/98 GT rear brakes, 03 Cobra 17" wheels, GM alt, 97 Z28 leather seats, soon: 97 Z28 T-56 6-spd, Ported heads w/SST full flow valves, 'R3' 276 cam, Edelbrock AFB Carb, GM HEI distributor, 8.8mm plug wires