Hello, I hope everyone is having a great day!
I've got an interesting problem. I just got through getting my engine
rebuilt (.020 over, 9.75:1 CR, roller rockers, gp2 cam, goodparts
triple ZS carbs (rebuilt) and headers). The cam has bee broken in and
the car has ran pretty strong for about 50 miles. However the day
before yesterday the engine began to miss terribly at all rpms.
Thinking that it was a timing/ignition problem, I swapped my Pertronix
ignition back to points. I checked each plug verify that I was
getting a good spark. No help. I then took out the spark plugs and
found that cylinders 1 & 2 were badly fouled. I replaced the plugs
with little or no effect.
Here is pretty much a run down of the situation:
1. I'm pretty sure my ignition and fuel are OK. The fuel filter is new.
2. The distributor has been rebuilt. I initially had a Pertronix
ignition, but I replaced them with points/condenser. I further
replaced those with spares, along with cap, rotor, plugs and wires.
3. At idle (or at any rpm really) I have a pronounced miss. If I take
the spark plug wires off of cylinder #1 and/or #2 there is very little
change in idle. If I take the plug wire off any other plug there is a
pronounced degradation in idle quality. So the problem is definitely
with cylinders #1 and #2.
4. If raise the piston on carb #1 (.25in - .50in) the idle raises by
about 500 rpm and the miss more-or-less goes away.
5. The #1 carb is leaking somewhere, but I can't isolate where.
6. I think at this point that the issue is carburetor related, so I
take the #1 carb off and make sure the fuel valve is clean and checked
the float level, all appeared within spec. I reassemble and test; No
change.
7. Interestingly enough, in the float bowl of #1 carb, I find a small
cylindrical piece of aluminum (I think, but it's not magnetic). It
looks like a rounded pellet about 4mm in diameter. Click on this link
for a pic of it:
http://photos.little-lamb.com/displayimage.php?pos=-393
8. Just for kicks, I did a compression test, 150psi across the board.
Does anyone have any suggestions on what the next step is?
Thanks for your help.
-Shannon
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