Pretty much anytime someone has the distributor out, does internal engine work that involves rotating the engine, and then it won’t start when all back together is because the distributor is 180* out. Ask me how I know lol.
Engine Can't get the motor to fire.
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I figured this was fairly applicable here so I wanted to post the information up as it may be useful to some. Mostly this is on how I make a tool to establish TDC out of an old spark plug, all thread, and a hex nut. I don't trust harmonic balancers to be 100% until I do this and make sure that TDC on the balancer is truely TDC. This is due them being mismarked and on the OEM units the outer ring slipping on the inner ring.
This is from Crane Cams website on how to correctly establish TDC using to positive stop device which you can buy:
How Do You Find Top Dead Center (T.D.C.)?
Determining exactly where Top Dead Center is can be tricky. The problem in finding the true T.D.C. of the piston's travel is that the piston dwells at T.D.C. for several degrees of crankshaft rotation. You must use a device to stop the piston in the same position on either side of T.D.C. and take readings from the degree wheel.
You will then split the difference in these readings and move the pointer this amount, making it the true T.D.C. point. Begin the procedure by first mounting the degree wheel on the end of the crankshaft securely, and rotating the engine to approximately T.D.C. Mount the pointer and line it up at zero on the degree wheel. Now rotate the engine to move the piston down into the cylinder. Install your positive stop device into the spark plug hole and extend the bolt and lock it into place with the jam nut. Now hand turn the engine (do not use the starter motor or you will put a hole through the piston), rotating until the piston comes up and stops against the bolt. Look at the degree wheel and write down the number of degrees shown by the pointer.
Hand turn the engine in the opposite direction until the piston comes up and stops on the bolt again. Go back to the degree wheel and write down the degrees it now reads. Add these two readings together and divide the answer by two. Now either move your pointer by this many degrees, or carefully loosen the degree wheel (without disturbing the position of the crankshaft) and move the wheel this required amount. Retighten the bolts, and rotate the engine again making sure that the readings on each side of T.D.C. are equal degrees away from zero. If they are, the zero on the degree wheel will now be the true T.D.C. point. Remove the positive stop device from the spark plug hole, as this procedure is complete.
My dad showed me how to make a positive stop device back in high school by hollowing out a used old spark plug from the car in question and then tapping it for 3/8-16 all thread. Next cut an 8" length of 3/8-16 all thread and round one end off as that end will contact the top of the piston. Thread the all thread into the tapped spark plug so the the rounded end is on the same side of the spark plug that threads into the cylinder head. Now run the nut down on the side of the spark plug that will be outside the cylinder head as this will be your jam nut.
Here is the positive stop device ready to install where the spark plug would thread into the head:
Yours might be different depending on the type of spark plug your head requires. The heads on my cars are Edelbrock Performer RPM's and AFR 185's and they use the same plug.
You do not need a degree wheel to do this as they are about impossible to install on a motor that has all the accessories already mounted on it. Just mark the balancer at the two stop points, use a tailor's tape (fabric tape measure that you can buy at Walmart) to measure the distance between them, divide by two, and then mark the mid-point which is TDC.
When you bring the motor up to TDC the rotor should be pointing directly at post the #1 cylinder spark plug wire is attached to. Most of the distributor caps are marked with a "1" and that is where the #1 cylinder plug wire goes. If not then pull the dizzy and reinstall so that the rotor is pointing directly at the #1 cylinder post on the cap of the dizzy. From this point you hook up the rest of the plug wires in the correct firing order. The motor will fire up with the distributor clocked in this position but you will have to time the motor with the spout connecotor out. A good base timing without a chip is 14 degrees ATDC. Each tuner has a base time they want the car timed to and it is usually 10 degrees ATDC.
This is from Crane Cams website on how to correctly establish TDC using to positive stop device which you can buy:
How Do You Find Top Dead Center (T.D.C.)?
Determining exactly where Top Dead Center is can be tricky. The problem in finding the true T.D.C. of the piston's travel is that the piston dwells at T.D.C. for several degrees of crankshaft rotation. You must use a device to stop the piston in the same position on either side of T.D.C. and take readings from the degree wheel.
You will then split the difference in these readings and move the pointer this amount, making it the true T.D.C. point. Begin the procedure by first mounting the degree wheel on the end of the crankshaft securely, and rotating the engine to approximately T.D.C. Mount the pointer and line it up at zero on the degree wheel. Now rotate the engine to move the piston down into the cylinder. Install your positive stop device into the spark plug hole and extend the bolt and lock it into place with the jam nut. Now hand turn the engine (do not use the starter motor or you will put a hole through the piston), rotating until the piston comes up and stops against the bolt. Look at the degree wheel and write down the number of degrees shown by the pointer.
Hand turn the engine in the opposite direction until the piston comes up and stops on the bolt again. Go back to the degree wheel and write down the degrees it now reads. Add these two readings together and divide the answer by two. Now either move your pointer by this many degrees, or carefully loosen the degree wheel (without disturbing the position of the crankshaft) and move the wheel this required amount. Retighten the bolts, and rotate the engine again making sure that the readings on each side of T.D.C. are equal degrees away from zero. If they are, the zero on the degree wheel will now be the true T.D.C. point. Remove the positive stop device from the spark plug hole, as this procedure is complete.
My dad showed me how to make a positive stop device back in high school by hollowing out a used old spark plug from the car in question and then tapping it for 3/8-16 all thread. Next cut an 8" length of 3/8-16 all thread and round one end off as that end will contact the top of the piston. Thread the all thread into the tapped spark plug so the the rounded end is on the same side of the spark plug that threads into the cylinder head. Now run the nut down on the side of the spark plug that will be outside the cylinder head as this will be your jam nut.
Here is the positive stop device ready to install where the spark plug would thread into the head:
Yours might be different depending on the type of spark plug your head requires. The heads on my cars are Edelbrock Performer RPM's and AFR 185's and they use the same plug.
You do not need a degree wheel to do this as they are about impossible to install on a motor that has all the accessories already mounted on it. Just mark the balancer at the two stop points, use a tailor's tape (fabric tape measure that you can buy at Walmart) to measure the distance between them, divide by two, and then mark the mid-point which is TDC.
When you bring the motor up to TDC the rotor should be pointing directly at post the #1 cylinder spark plug wire is attached to. Most of the distributor caps are marked with a "1" and that is where the #1 cylinder plug wire goes. If not then pull the dizzy and reinstall so that the rotor is pointing directly at the #1 cylinder post on the cap of the dizzy. From this point you hook up the rest of the plug wires in the correct firing order. The motor will fire up with the distributor clocked in this position but you will have to time the motor with the spout connecotor out. A good base timing without a chip is 14 degrees ATDC. Each tuner has a base time they want the car timed to and it is usually 10 degrees ATDC.
WTF???? Take off the valve cover and after the intake valve moves you will be at TDC when the timing mark hits zero... Easy schmeezyI figured this was fairly applicable here so I wanted to post the information up as it may be useful to some. Mostly this is on how I make a tool to establish TDC out of an old spark plug, all thread, and a hex nut. I don't trust harmonic balancers to be 100% until I do this and make sure that TDC on the balancer is truely TDC. This is due them being mismarked and on the OEM units the outer ring slipping on the inner ring.
This is from Crane Cams website on how to correctly establish TDC using to positive stop device which you can buy:
How Do You Find Top Dead Center (T.D.C.)?
Determining exactly where Top Dead Center is can be tricky. The problem in finding the true T.D.C. of the piston's travel is that the piston dwells at T.D.C. for several degrees of crankshaft rotation. You must use a device to stop the piston in the same position on either side of T.D.C. and take readings from the degree wheel.
You will then split the difference in these readings and move the pointer this amount, making it the true T.D.C. point. Begin the procedure by first mounting the degree wheel on the end of the crankshaft securely, and rotating the engine to approximately T.D.C. Mount the pointer and line it up at zero on the degree wheel. Now rotate the engine to move the piston down into the cylinder. Install your positive stop device into the spark plug hole and extend the bolt and lock it into place with the jam nut. Now hand turn the engine (do not use the starter motor or you will put a hole through the piston), rotating until the piston comes up and stops against the bolt. Look at the degree wheel and write down the number of degrees shown by the pointer.
Hand turn the engine in the opposite direction until the piston comes up and stops on the bolt again. Go back to the degree wheel and write down the degrees it now reads. Add these two readings together and divide the answer by two. Now either move your pointer by this many degrees, or carefully loosen the degree wheel (without disturbing the position of the crankshaft) and move the wheel this required amount. Retighten the bolts, and rotate the engine again making sure that the readings on each side of T.D.C. are equal degrees away from zero. If they are, the zero on the degree wheel will now be the true T.D.C. point. Remove the positive stop device from the spark plug hole, as this procedure is complete.
My dad showed me how to make a positive stop device back in high school by hollowing out a used old spark plug from the car in question and then tapping it for 3/8-16 all thread. Next cut an 8" length of 3/8-16 all thread and round one end off as that end will contact the top of the piston. Thread the all thread into the tapped spark plug so the the rounded end is on the same side of the spark plug that threads into the cylinder head. Now run the nut down on the side of the spark plug that will be outside the cylinder head as this will be your jam nut.
Here is the positive stop device ready to install where the spark plug would thread into the head:
Yours might be different depending on the type of spark plug your head requires. The heads on my cars are Edelbrock Performer RPM's and AFR 185's and they use the same plug.
You do not need a degree wheel to do this as they are about impossible to install on a motor that has all the accessories already mounted on it. Just mark the balancer at the two stop points, use a tailor's tape (fabric tape measure that you can buy at Walmart) to measure the distance between them, divide by two, and then mark the mid-point which is TDC.
When you bring the motor up to TDC the rotor should be pointing directly at post the #1 cylinder spark plug wire is attached to. Most of the distributor caps are marked with a "1" and that is where the #1 cylinder plug wire goes. If not then pull the dizzy and reinstall so that the rotor is pointing directly at the #1 cylinder post on the cap of the dizzy. From this point you hook up the rest of the plug wires in the correct firing order. The motor will fire up with the distributor clocked in this position but you will have to time the motor with the spout connecotor out. A good base timing without a chip is 14 degrees ATDC. Each tuner has a base time they want the car timed to and it is usually 10 degrees ATDC.
If you go back and read the thread he got it running and then accused me of being a 'ROCK STAR'
if he's your only groupie, you be illinIf you go back and read the thread he got it running and then accused me of being a 'ROCK STAR'
Limp,
By the time I pull all the stuff off my motor to get to the valve cover to look at the rocker arms I would done and on my fourth beer with how I do it. It’s a bit different with injection.
By the time I pull all the stuff off my motor to get to the valve cover to look at the rocker arms I would done and on my fourth beer with how I do it. It’s a bit different with injection.
I am thinking carb so yeah.......
Just looking for a simple way to find tdc after reading the cam degreeing post......
I like that red motor...Lets see some more of what your working on. Glad to see it going after all the time you have in it
Build thread is in my sig. I do need to update it though.
This was a couple of days ago......
This was a couple of days ago......
Gs1987GT
Active Member
General, you've just provided us with the definition of an expert, and I do consider you to be just that with these cars. An expert is someone who has made every conceivable error in a defined field. That's what makes one an expert. Great advice and guidance as usual Sir. Thanks.
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