5.0L makes a Pop, Pop in the Carb
 

I have a 2001 20'Glastron with a 5.0L Volvo SX. From 3/4 to WOT it
makes a loud Pop...Pop...Pop in the Carburetor. It does a pop about
every second. I have replaced the Power Valve in the two Barrel holley
Carb and rebuilt the carb but it did not change or fix the problem.

Any Ideas on what could be wrong?

Kevin

5.0L makes a Pop, Pop in the Carb
 

Could be;
(A) burnt intake valve seat
(B) cross fire between ignition wires
(C) arcing in the distributor cap
run the engine at night and look for glowing or arcing wires. If you see
none then pull the distributor cap (if equipped) and look for light gray
traces between the terminals.
Worst case scenario....do a compression check. You may have a burnt intake
valve and seat.
Good Luck...I hope it's the wires!
Charles

5.0L makes a Pop, Pop in the Carb
 

On Sat, 19 Jul 2003 20:21:11 -0500, "Ervin Charles"
wrote:

Could be;
(A) burnt intake valve seat
(B) cross fire between ignition wires
(C) arcing in the distributor cap
run the engine at night and look for glowing or arcing wires. If you see
none then pull the distributor cap (if equipped) and look for light gray
traces between the terminals.
Worst case scenario....do a compression check. You may have a burnt intake
valve and seat.
Good Luck...I hope it's the wires!
Charles



Yes, also check stuffed for plugs.
He may have wires order stuffed up to.
A vacume gauge will test out his system quite well to.
And put a timing light on it

But its not his carb, as he thinks - so it seems he hasnt checked his
distributor -which is 90% probability. either he has moisture of
carbon fluff in it, and it has arc tracking - under load.

And don't take the cover off the carb while its popping-
It can set your face and boat alight that one, if your not careful.

5.0L makes a Pop, Pop in the Carb
 

My dad's GM305 (5L) Volvo was doing same thing. Tuned up, rebuilt carb,
new coil, no better. Removed valve covers, no broken rockers or springs
but one lobe on cam is just about gone. Very hard to change cam without
pulling motor. Changed prop to bring rpm down. Has been exceptable for
three years now. He doesn't leave the dock a whole lot though.


Kevin wrote:

I have a 2001 20'Glastron with a 5.0L Volvo SX. From 3/4 to WOT it
makes a loud Pop...Pop...Pop in the Carburetor. It does a pop about
every second. I have replaced the Power Valve in the two Barrel holley
Carb and rebuilt the carb but it did not change or fix the problem.

Any Ideas on what could be wrong?

Kevin

5.0L makes a Pop, Pop in the Carb
 

Brian Stephenson wrote in message ...
My dad's GM305 (5L) Volvo was doing same thing. Tuned up, rebuilt carb,
new coil, no better. Removed valve covers, no broken rockers or springs
but one lobe on cam is just about gone. Very hard to change cam without
pulling motor. Changed prop to bring rpm down. Has been exceptable for
three years now. He doesn't leave the dock a whole lot though.


Chevy small blocks had the popping problem, caused by worn cam
lobes. A worn lobe fails to open one exhaust valve sufficiently, and
the exhaust gas pressures that remain in the cylinder after the
exhaust stroke will pop back into the intake on acceleration.
Cylinder pressures tend to be highest at acceleration.
Another cause could be lean mixture, but that's usually only a
problem when the engine is cold.

Dan