Jason,
You didnt mention what the main jets are/were.
These, and the choke "venturi" side are the things
that effect the running/power mixture not the pump
discharge nozzle, and idle tube/ jet.
The chokes are marked with a number, but could
possibly be measured in the carb. The chokes run
from 27mm to 30mm for the special tuning option
offered by rootes.
Also, some carbs are jeted for paper ellement filter,
and some are jetted for bird catchers, running paper
ellement filters with carbs setup for the bird cather
will tend to run rather rich due to the restricivity
of the filters.
In the sunbeam alpine I-IV, there is a table in the zenith
WIA/WIP section that describes the jets, air bleeds and
chokes for all zenith applications.
Hope this helps,
Jarrid Gross
-----Original Message-----
From: owner-alpines@autox.team.net
[mailto:owner-alpines@autox.team.net]On Behalf Of Raser, Jason
Sent: Tuesday, October 02, 2001 6:32 AM
To: alpines@autox.team.net
Subject: Zenith Carbs - Jetting
You may recall I have a Series 2 that doesn't seem to run right. I think
I'm getting close to a solution.
I think I have eliminated all other possibile problems and everything points
to my Zenith Carbs. Scott was kind enough to send me the article "To carb
and Alpine."
Before I go ahead and rejet these carbs (they are NOS, so I've done all I
can to avoid opening them) I wonder if anyone has the experience I've had or
if you could direct me to the most knowlegeable person about jets for an
Alpine.
Turns out the carbs I have are:
C1688F
36WIP-2
1046674
and
C1688R
36WIP-2
1046874
The carbs I took off the car after I bought it were:
C3744F
36WIP-3
1800118
and
C1744R
36WIP-3
1800119
>From the article Scott sent me I see that the differences are:
Carb & Car Pump discharge Nozzle Idle Tube
36WIP-2 (S2) 50 50
36WIP-3 (S2) 70 45
New parts (or rebuilt):
Carbs
Generator
Distributor (45D from Moss Motors)
Mechanical fuel pump (from Sunbeam Specialties) (I've tried an electric pump
too)
New coil connected to a ballast resistor (a mechanic put this on)
Clean fuel tank
Engine compression:
1 120 psi
2 121 psi
3 120 psi
4 125 psi
I put a fuel regulator after the fuel pump to ensure that I've got the right
fuel pressure. I adjusted the carbs to run a bit rich and I can drive the
car. Runs fine on the flat spots but struggles very hard up the hills.
Have to keep it at 3,000-4,000 rpm.
I made sure my polarity on my coil is correct with the spark jumping from
the plug toward the plug wire. It jumps a good 1/4 inch or more.
I pulled the plugs and each of them are fine black powdery, naturally
because it's running too rich.
If I simply change the pump discharge nozzle and idle tube, could this
correct my problem by allowing me to run the carbs lean.
Any ideas would be appreciated.
Jason Raser
|