I have a1982 Cb750C that i am rebuilding. everything is going well except #4 cylinder is not firing. I have replaced the plugs cleaned the carbs twice, syncronized the carbs, and set the pilot jets to the initial setting. I can smell fuel out of hte exhaust there ,since i have a 4-4 exaust, but it just doesn fire, there are no build up on the plug or residue. It did have a plastic tee in the fuelines between #3 & #4 but i took it out woudl that casue this? I am running out of ideas any suggestions, or solutions would be great.
Well see that is the weird part. It only has two coils and #1 & #4 share the same coil. I even have switched the two (don't worry on this bike #1 & #4 fire at the same time) and I get the same result so it's not the coilsWell see that is the weird part. It only has two coils and #1 & #4 share the same coil. I even have switched the two (don't worry on this bike #1 & #4 fire at the same time) and I get the same result so it's not the coils
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NO YEAR TOLD... 1993 TO 1996?
CORRECT NAME (NO SPACE BEFORE C)
Hyundai Scoupe?
ALL 4 BANGERS ARE 1,3,4,2
EXCEPT BOXER ENGINES (PANCAKE MOTORS)
IS THIS A SPARK QUESTION?
OR CAM TIMING QUESTION.?
hi seth if you remove the spark plug from the cylinder head and rest it against the side of it against the cylinder head you should be able to see if it is firing while you crank the motor. otherwise a spark plug tester can be installed in place of the spark plug
have you checked for codes. you should have power and ground at the coil plug. note the computer is what grounds the circuit to fire the ignition coil. if you don`t have a ground then it could be a bad coil driver in the computer, which means you will have to have the computer replaced a possibly programed to the car.
no, the plug is firing. But the timing is off. the plug is firing quite a bit before top dead center on that cylinder. The burning of the fuel mixture is occurring while that piston is on its way up and is slowing it down---dragging down the whole engine. i think you should change the distributor cap and rotor as cylinder one is firing at the same time as cylinder 2or 4. This indicates a possible carbon track in the distributor cap.
If your firing order is correct(165432), then I would suspect the drenched coil pack. That oily antifreeze will penetrate every nook and cranny of the coil. It's probably shorting out and cross-firing. I would go ahead and replace it. Double check your firing order again. The back cylinders are 2-4-6, counting from to back, but that is not the firing order. The plug wires would attach to the coils in the following order, counting from the front of the coils(nearest to the front of the car)to the rear:1-4-5-2-3-6.Let me know if any of this helps you. Good Luck.
#1 cylinder not firing, check spark plug, spark plug wire, remove spark plug and use a compression tester, and check the compression of that cylinder. should have at least 65 pounds of compression per cylinder. If the compression is low, you may try shooting a little oil in to that cylinder, replace spark plug, and try running motor again. if the compression is low on said cylinder, could be due to bad piston rings. requiring a motor rebuild.
Nice friend. If you can figure out which terminal on the distributor is for #1 (cylinder at front of engine), this diagram from AutoZone.com should work for you. Look for a #1 mark on the distributor.
Firing order is stamped on the block intake manifold or label. 4 cyl are typically 1324
From the web: The
firing order for four cylinder engines where the cylinders are in-line
is 1243 or 1342.
Those
are the only two possibilities I've ever found for inline four
cylinder engines. In practice, it's almost always 1342, except
for Ford engines which are 1243.
Take one off at a time and replace it
Do not run the wires parallel (side-by-side) for more than 6". Cross them over each other wavy-like if needed. This will prevent crossfire.
Replace Points, Plugs, Condenser, Rotor and Cap too.
Engine Firing Order: 1-3-4-2-nl-> Distributor Rotation: Clockwise" rel="width:950,height:660" index="0" $included="null">
Fig. Fig. 1: 4-Cylinder Engines-Except FWD GLC-nl-> Engine Firing Order: 1-3-4-2-nl-> Distributor Rotation: Clockwise
Well see that is the weird part. It only has two coils and #1 & #4 share the same coil. I even have switched the two (don't worry on this bike #1 & #4 fire at the same time) and I get the same result so it's not the coils
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