258 carburetor adjustment
 

I have an 85 with an aftermarket non computer controlled carter bbd carb.
What is the procedure for setting the 2 adjutable screws with springs around
them on the front lower portion of the carb.

Re: 258 carburetor adjustment
 

You are supposed to first make sure you have the computer out of 'limp
home' mode or the engine will run like a bag of dirt. To do this you
use the 'Nutter' bypass which hooks the ignition module directly to the
distributor.

I use 2 new wires and just hook the orange and purple wires directly
together at the distributor and module rather than mess inside the
wiring harness. Here is a link on it:
http://home.sprynet.com/~dale02/ignmods.htm

Once the timing is set, you start with the idle mix screws 5 or 6 turns
out. The engine will run like this, but the idle will need adjusting.

You get it running and start turning both screws in 1/4 turn at a time.
Between each turn, you give the gas linkage a shot to rev it up.
Continue on, maybe adjusting the carb every time it goes off 50 rpm,
until the engine starts to lean stumble. It will be obvious when that
last 1/4 turn makes a difference. You then back both screws off 1/4
turn and you are god to go.



mark wrote:
>
> I have an 85 with an aftermarket non computer controlled carter bbd carb.
> What is the procedure for setting the 2 adjutable screws with springs around
> them on the front lower portion of the carb.

Re: 258 carburetor adjustment
 

You are supposed to first make sure you have the computer out of 'limp
home' mode or the engine will run like a bag of dirt. To do this you
use the 'Nutter' bypass which hooks the ignition module directly to the
distributor.

I use 2 new wires and just hook the orange and purple wires directly
together at the distributor and module rather than mess inside the
wiring harness. Here is a link on it:
http://home.sprynet.com/~dale02/ignmods.htm

Once the timing is set, you start with the idle mix screws 5 or 6 turns
out. The engine will run like this, but the idle will need adjusting.

You get it running and start turning both screws in 1/4 turn at a time.
Between each turn, you give the gas linkage a shot to rev it up.
Continue on, maybe adjusting the carb every time it goes off 50 rpm,
until the engine starts to lean stumble. It will be obvious when that
last 1/4 turn makes a difference. You then back both screws off 1/4
turn and you are god to go.



mark wrote:
>
> I have an 85 with an aftermarket non computer controlled carter bbd carb.
> What is the procedure for setting the 2 adjutable screws with springs around
> them on the front lower portion of the carb.

Re: 258 carburetor adjustment
 

You are supposed to first make sure you have the computer out of 'limp
home' mode or the engine will run like a bag of dirt. To do this you
use the 'Nutter' bypass which hooks the ignition module directly to the
distributor.

I use 2 new wires and just hook the orange and purple wires directly
together at the distributor and module rather than mess inside the
wiring harness. Here is a link on it:
http://home.sprynet.com/~dale02/ignmods.htm

Once the timing is set, you start with the idle mix screws 5 or 6 turns
out. The engine will run like this, but the idle will need adjusting.

You get it running and start turning both screws in 1/4 turn at a time.
Between each turn, you give the gas linkage a shot to rev it up.
Continue on, maybe adjusting the carb every time it goes off 50 rpm,
until the engine starts to lean stumble. It will be obvious when that
last 1/4 turn makes a difference. You then back both screws off 1/4
turn and you are god to go.



mark wrote:
>
> I have an 85 with an aftermarket non computer controlled carter bbd carb.
> What is the procedure for setting the 2 adjutable screws with springs around
> them on the front lower portion of the carb.

Re: 258 carburetor adjustment
 

I did the bypass and also have an aftermarket bbd with no wires and a manual
choke. The EGR is unhooked and pluged at intake and exhaust manifold. O2
sensor disconnected. I tore apart the carb today hoping to find some dirt in
the idle tubes but they are clean (years ago I drilled them out to 0.032) I
took off the intake manifold hoping for a cracked gasket but it lookes great
but I think I will add an extra gasket anyway. Should the mixture screws be
adjusted the same? 1 was out 2.5 turns and the other was out 4.5 turns.
Could this be part of the problem? The symtoms feel like it is not running
on all cylinders. Plugs, wires, cap and rotor all new.
It does seem to idle all right but stalls easily when givin too much
throttle.


"Mike Romain" <romainm@sympatico.ca> wrote in message
news:44B561A9.E997353C@sympatico.ca...
> You are supposed to first make sure you have the computer out of 'limp
> home' mode or the engine will run like a bag of dirt. To do this you
> use the 'Nutter' bypass which hooks the ignition module directly to the
> distributor.
>
> I use 2 new wires and just hook the orange and purple wires directly
> together at the distributor and module rather than mess inside the
> wiring harness. Here is a link on it:
> http://home.sprynet.com/~dale02/ignmods.htm
>
> Once the timing is set, you start with the idle mix screws 5 or 6 turns
> out. The engine will run like this, but the idle will need adjusting.
>
> You get it running and start turning both screws in 1/4 turn at a time.
> Between each turn, you give the gas linkage a shot to rev it up.
> Continue on, maybe adjusting the carb every time it goes off 50 rpm,
> until the engine starts to lean stumble. It will be obvious when that
> last 1/4 turn makes a difference. You then back both screws off 1/4
> turn and you are god to go.
>
>
>
> mark wrote:
>>
>> I have an 85 with an aftermarket non computer controlled carter bbd carb.
>> What is the procedure for setting the 2 adjutable screws with springs
>> around
>> them on the front lower portion of the carb.

Re: 258 carburetor adjustment
 

I did the bypass and also have an aftermarket bbd with no wires and a manual
choke. The EGR is unhooked and pluged at intake and exhaust manifold. O2
sensor disconnected. I tore apart the carb today hoping to find some dirt in
the idle tubes but they are clean (years ago I drilled them out to 0.032) I
took off the intake manifold hoping for a cracked gasket but it lookes great
but I think I will add an extra gasket anyway. Should the mixture screws be
adjusted the same? 1 was out 2.5 turns and the other was out 4.5 turns.
Could this be part of the problem? The symtoms feel like it is not running
on all cylinders. Plugs, wires, cap and rotor all new.
It does seem to idle all right but stalls easily when givin too much
throttle.


"Mike Romain" <romainm@sympatico.ca> wrote in message
news:44B561A9.E997353C@sympatico.ca...
> You are supposed to first make sure you have the computer out of 'limp
> home' mode or the engine will run like a bag of dirt. To do this you
> use the 'Nutter' bypass which hooks the ignition module directly to the
> distributor.
>
> I use 2 new wires and just hook the orange and purple wires directly
> together at the distributor and module rather than mess inside the
> wiring harness. Here is a link on it:
> http://home.sprynet.com/~dale02/ignmods.htm
>
> Once the timing is set, you start with the idle mix screws 5 or 6 turns
> out. The engine will run like this, but the idle will need adjusting.
>
> You get it running and start turning both screws in 1/4 turn at a time.
> Between each turn, you give the gas linkage a shot to rev it up.
> Continue on, maybe adjusting the carb every time it goes off 50 rpm,
> until the engine starts to lean stumble. It will be obvious when that
> last 1/4 turn makes a difference. You then back both screws off 1/4
> turn and you are god to go.
>
>
>
> mark wrote:
>>
>> I have an 85 with an aftermarket non computer controlled carter bbd carb.
>> What is the procedure for setting the 2 adjutable screws with springs
>> around
>> them on the front lower portion of the carb.

Re: 258 carburetor adjustment
 

I did the bypass and also have an aftermarket bbd with no wires and a manual
choke. The EGR is unhooked and pluged at intake and exhaust manifold. O2
sensor disconnected. I tore apart the carb today hoping to find some dirt in
the idle tubes but they are clean (years ago I drilled them out to 0.032) I
took off the intake manifold hoping for a cracked gasket but it lookes great
but I think I will add an extra gasket anyway. Should the mixture screws be
adjusted the same? 1 was out 2.5 turns and the other was out 4.5 turns.
Could this be part of the problem? The symtoms feel like it is not running
on all cylinders. Plugs, wires, cap and rotor all new.
It does seem to idle all right but stalls easily when givin too much
throttle.


"Mike Romain" <romainm@sympatico.ca> wrote in message
news:44B561A9.E997353C@sympatico.ca...
> You are supposed to first make sure you have the computer out of 'limp
> home' mode or the engine will run like a bag of dirt. To do this you
> use the 'Nutter' bypass which hooks the ignition module directly to the
> distributor.
>
> I use 2 new wires and just hook the orange and purple wires directly
> together at the distributor and module rather than mess inside the
> wiring harness. Here is a link on it:
> http://home.sprynet.com/~dale02/ignmods.htm
>
> Once the timing is set, you start with the idle mix screws 5 or 6 turns
> out. The engine will run like this, but the idle will need adjusting.
>
> You get it running and start turning both screws in 1/4 turn at a time.
> Between each turn, you give the gas linkage a shot to rev it up.
> Continue on, maybe adjusting the carb every time it goes off 50 rpm,
> until the engine starts to lean stumble. It will be obvious when that
> last 1/4 turn makes a difference. You then back both screws off 1/4
> turn and you are god to go.
>
>
>
> mark wrote:
>>
>> I have an 85 with an aftermarket non computer controlled carter bbd carb.
>> What is the procedure for setting the 2 adjutable screws with springs
>> around
>> them on the front lower portion of the carb.

Re: 258 carburetor adjustment
 

They need to be the same. Sometimes a spring is weak allowing the one
to loosen and sometimes someone loosens one to make up for a plugged
idle tube.

2.5 turns is pretty lean. That will cause a rumble at idle in half the
engine while the other half is idling rich. Should sound fairly
strange....

Mike

mark wrote:
>
> I did the bypass and also have an aftermarket bbd with no wires and a manual
> choke. The EGR is unhooked and pluged at intake and exhaust manifold. O2
> sensor disconnected. I tore apart the carb today hoping to find some dirt in
> the idle tubes but they are clean (years ago I drilled them out to 0.032) I
> took off the intake manifold hoping for a cracked gasket but it lookes great
> but I think I will add an extra gasket anyway. Should the mixture screws be
> adjusted the same? 1 was out 2.5 turns and the other was out 4.5 turns.
> Could this be part of the problem? The symtoms feel like it is not running
> on all cylinders. Plugs, wires, cap and rotor all new.
> It does seem to idle all right but stalls easily when givin too much
> throttle.
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:44B561A9.E997353C@sympatico.ca...
> > You are supposed to first make sure you have the computer out of 'limp
> > home' mode or the engine will run like a bag of dirt. To do this you
> > use the 'Nutter' bypass which hooks the ignition module directly to the
> > distributor.
> >
> > I use 2 new wires and just hook the orange and purple wires directly
> > together at the distributor and module rather than mess inside the
> > wiring harness. Here is a link on it:
> > http://home.sprynet.com/~dale02/ignmods.htm
> >
> > Once the timing is set, you start with the idle mix screws 5 or 6 turns
> > out. The engine will run like this, but the idle will need adjusting.
> >
> > You get it running and start turning both screws in 1/4 turn at a time.
> > Between each turn, you give the gas linkage a shot to rev it up.
> > Continue on, maybe adjusting the carb every time it goes off 50 rpm,
> > until the engine starts to lean stumble. It will be obvious when that
> > last 1/4 turn makes a difference. You then back both screws off 1/4
> > turn and you are god to go.
> >
> >
> >
> > mark wrote:
> >>
> >> I have an 85 with an aftermarket non computer controlled carter bbd carb.
> >> What is the procedure for setting the 2 adjutable screws with springs
> >> around
> >> them on the front lower portion of the carb.

Re: 258 carburetor adjustment
 

They need to be the same. Sometimes a spring is weak allowing the one
to loosen and sometimes someone loosens one to make up for a plugged
idle tube.

2.5 turns is pretty lean. That will cause a rumble at idle in half the
engine while the other half is idling rich. Should sound fairly
strange....

Mike

mark wrote:
>
> I did the bypass and also have an aftermarket bbd with no wires and a manual
> choke. The EGR is unhooked and pluged at intake and exhaust manifold. O2
> sensor disconnected. I tore apart the carb today hoping to find some dirt in
> the idle tubes but they are clean (years ago I drilled them out to 0.032) I
> took off the intake manifold hoping for a cracked gasket but it lookes great
> but I think I will add an extra gasket anyway. Should the mixture screws be
> adjusted the same? 1 was out 2.5 turns and the other was out 4.5 turns.
> Could this be part of the problem? The symtoms feel like it is not running
> on all cylinders. Plugs, wires, cap and rotor all new.
> It does seem to idle all right but stalls easily when givin too much
> throttle.
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:44B561A9.E997353C@sympatico.ca...
> > You are supposed to first make sure you have the computer out of 'limp
> > home' mode or the engine will run like a bag of dirt. To do this you
> > use the 'Nutter' bypass which hooks the ignition module directly to the
> > distributor.
> >
> > I use 2 new wires and just hook the orange and purple wires directly
> > together at the distributor and module rather than mess inside the
> > wiring harness. Here is a link on it:
> > http://home.sprynet.com/~dale02/ignmods.htm
> >
> > Once the timing is set, you start with the idle mix screws 5 or 6 turns
> > out. The engine will run like this, but the idle will need adjusting.
> >
> > You get it running and start turning both screws in 1/4 turn at a time.
> > Between each turn, you give the gas linkage a shot to rev it up.
> > Continue on, maybe adjusting the carb every time it goes off 50 rpm,
> > until the engine starts to lean stumble. It will be obvious when that
> > last 1/4 turn makes a difference. You then back both screws off 1/4
> > turn and you are god to go.
> >
> >
> >
> > mark wrote:
> >>
> >> I have an 85 with an aftermarket non computer controlled carter bbd carb.
> >> What is the procedure for setting the 2 adjutable screws with springs
> >> around
> >> them on the front lower portion of the carb.

Re: 258 carburetor adjustment
 

They need to be the same. Sometimes a spring is weak allowing the one
to loosen and sometimes someone loosens one to make up for a plugged
idle tube.

2.5 turns is pretty lean. That will cause a rumble at idle in half the
engine while the other half is idling rich. Should sound fairly
strange....

Mike

mark wrote:
>
> I did the bypass and also have an aftermarket bbd with no wires and a manual
> choke. The EGR is unhooked and pluged at intake and exhaust manifold. O2
> sensor disconnected. I tore apart the carb today hoping to find some dirt in
> the idle tubes but they are clean (years ago I drilled them out to 0.032) I
> took off the intake manifold hoping for a cracked gasket but it lookes great
> but I think I will add an extra gasket anyway. Should the mixture screws be
> adjusted the same? 1 was out 2.5 turns and the other was out 4.5 turns.
> Could this be part of the problem? The symtoms feel like it is not running
> on all cylinders. Plugs, wires, cap and rotor all new.
> It does seem to idle all right but stalls easily when givin too much
> throttle.
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:44B561A9.E997353C@sympatico.ca...
> > You are supposed to first make sure you have the computer out of 'limp
> > home' mode or the engine will run like a bag of dirt. To do this you
> > use the 'Nutter' bypass which hooks the ignition module directly to the
> > distributor.
> >
> > I use 2 new wires and just hook the orange and purple wires directly
> > together at the distributor and module rather than mess inside the
> > wiring harness. Here is a link on it:
> > http://home.sprynet.com/~dale02/ignmods.htm
> >
> > Once the timing is set, you start with the idle mix screws 5 or 6 turns
> > out. The engine will run like this, but the idle will need adjusting.
> >
> > You get it running and start turning both screws in 1/4 turn at a time.
> > Between each turn, you give the gas linkage a shot to rev it up.
> > Continue on, maybe adjusting the carb every time it goes off 50 rpm,
> > until the engine starts to lean stumble. It will be obvious when that
> > last 1/4 turn makes a difference. You then back both screws off 1/4
> > turn and you are god to go.
> >
> >
> >
> > mark wrote:
> >>
> >> I have an 85 with an aftermarket non computer controlled carter bbd carb.
> >> What is the procedure for setting the 2 adjutable screws with springs
> >> around
> >> them on the front lower portion of the carb.