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jaredmcginness
Hey guys.

Me again, ready to be flamed. (I have a fire extinguisher biggrin.gif )

IPB Image


So to recap, I've completed my 1911. I just added the Dellortos, fresh rebuild, all new everything.
Running the motor on the ground. Fires right up. Idles high, spits, pops and runs for about 1 minute and bogs down and dies.

I can answer my own question, I assume the carbs have a poor A/F mixture... By the time everything cycles its not enough to keep it running.

Am I missing a factory setting to put the carbs at? Everyone I've spoken to says "back out the idle screws 1.5-2 turns from lightly seated", this should be enough to get the motor to idle like a tractor.

My main concern: I need to break in my cam. I am trying to run it 2-3K for 20 minutes. I've never let it hit a low idle rpm for any period of time. I don't want to keep doing this routine and diminish my chances of a proper cam break-in.

Carb specs: (although, nothing here should not allow it to at least run)
1911cc
Vent: 34
Main: 130
Idle: 60
Air: 180
Emulsion. .2
Pump jet: 35


VIDEO 1 - exhaust.




VIDEO 2 - RPM and Carb view


My fuel layout: Tank>filter>3 psi pump>filter>Regulator>T>Carbs
The power from the electric fuel pump is running to the starter tab. I.e. Receives power when starter is actuated. Is this correct?

Too long, did not read:
-Fresh motor, trying to break in cam.
-Cannot get carbs to run long enough to break in cam
-The carbs are not synched yet. I feel I need to break in the cam before anything.

This is my first rodeo, any advice is appreciated.
ndfrigi
can u check oil pressure?
bob164
The power to the fuel pump should come from the "run" position of the switch. The way you have it wired now has the fuel pump running only when starter runs then is cut off. The pump basically primes the bowls then the engine dies when the bowls are empty. You need the pump to be on when the switch is in the run position.

Hope this helps,
Bob

jaredmcginness
QUOTE(ndfrigi @ Nov 14 2020, 03:49 PM) *

can u check oil pressure?

Oil pressure reads well. I have a gauge attached. I believe it was just under 3 bar.

QUOTE(bob164 @ Nov 14 2020, 03:51 PM) *

The power to the fuel pump should come from the "run" position of the switch. The way you have it wired now has the fuel pump running only when starter runs then is cut off. The pump basically primes the bowls then the engine dies when the bowls are empty. You need the pump to be on when the switch is in the run position.




This makes complete sense. I'm way over thinking this for now if it is just a simple fueling issue, which it does seem like. I assumed the starter was constant after it was actuated.

I need to find a way to make shift a run position with the motor out of the car. I assume I will need to relay it.
ndfrigi
QUOTE(jaredmcginness @ Nov 14 2020, 01:11 PM) *

QUOTE(ndfrigi @ Nov 14 2020, 03:49 PM) *

can u check oil pressure?

Oil pressure reads well. I have a gauge attached. I believe it was just under 3 bar.

QUOTE(bob164 @ Nov 14 2020, 03:51 PM) *

The power to the fuel pump should come from the "run" position of the switch. The way you have it wired now has the fuel pump running only when starter runs then is cut off. The pump basically primes the bowls then the engine dies when the bowls are empty. You need the pump to be on when the switch is in the run position.




This makes complete sense. I'm way over thinking this for now if it is just a simple fueling issue, which it does seem like. I assumed the starter was constant after it was actuated.

I need to find a way to make shift a run position with the motor out of the car. I assume I will need to relay it.


I did test run my engine on my garage floor and I did hook my fuel pump directly to the battery.

Click to view attachment

here is one of my video.

https://imgur.com/user/ndfrigi

jaredmcginness
Thanks @ndfrigi This completely answers my question. Problem solved.

I ran the motor for 20 minutes @2700Rpm. Break in complete



I feel silly that it was just running out of gas. Thanks everyone.
ndfrigi
QUOTE(jaredmcginness @ Nov 14 2020, 01:45 PM) *

Thanks @ndfrigi This completely answers my question. Problem solved.

I ran the motor for 20 minutes @2700Rpm. Break in complete



I feel silly that it was just running out of gas. Thanks everyone.


yehey! congratulations!
now time to install the engine to your car!
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