67 427 how to establish TDC
#1
Drifting
Thread Starter
67 427 how to establish TDC
getting ready to drop in rebuilt distributor...have a pretty good Idea how to do it...but thought I would check w/ forum members..
1st don't want to remove drivers side valve cover..it's tight and does not leak.so want to do it another way .
2nd have #1 spark plug out and car is on TDC mark....but not 100% sure Im on the correct stroke..
I have not moved the engine since I pulled the distributor out...but rocked the car till I got it on TDC.
so if its (the rotor) is pointing to # 1 on the distributor cap is that ok?
3rd...or do I need to bump the engine over with starter and put finger over #1 spark plug hole till it blows and then re-establish TDC.and pointing to
# 1 spark plug position on the distributor cap? and then walk the distributor in...?
1st don't want to remove drivers side valve cover..it's tight and does not leak.so want to do it another way .
2nd have #1 spark plug out and car is on TDC mark....but not 100% sure Im on the correct stroke..
I have not moved the engine since I pulled the distributor out...but rocked the car till I got it on TDC.
so if its (the rotor) is pointing to # 1 on the distributor cap is that ok?
3rd...or do I need to bump the engine over with starter and put finger over #1 spark plug hole till it blows and then re-establish TDC.and pointing to
# 1 spark plug position on the distributor cap? and then walk the distributor in...?
Last edited by bluzrocker; 01-16-2017 at 05:24 PM.
#2
Race Director
Member Since: Mar 2009
Location: Canada's capital
Posts: 19,777
Received 4,583 Likes
on
2,157 Posts
2020 Corvette of the Year Finalist (appearance mods)
C1 of Year Finalist (appearance mods) 2019
I usually put my thumb in the sparkplug hole and tick it over slowly(obviously coil wire disconnected!) and feel for the compression stroke pushing against my thumb. Feel the pressure, line up the balancer, and that's it. Easy.
Of course if it's not the original balancer you may have to screw in a short bolt, turn it over by hand until it stops, mark the balancer, then go backwards until it comes up to the "stop" again, mark it again, and split the distance on the balancer. That's the sure way to get TDC. Or a dial indicator in the hole.
Of course if it's not the original balancer you may have to screw in a short bolt, turn it over by hand until it stops, mark the balancer, then go backwards until it comes up to the "stop" again, mark it again, and split the distance on the balancer. That's the sure way to get TDC. Or a dial indicator in the hole.
The following users liked this post:
bluzrocker (01-16-2017)
#3
Race Director
If you rocked the car to get on TDC on the timing marks you have lost your reference point. The last car I did this on I put a piece of tape over the spark plug hole after cleaning it well and rotated the engine until the tape blew off with an audible pop. Brought the balancer the rest of the way to rest on TDC and installed the distributor. An extra pair of hands can also help with using a finger over the plug hole while you turn the engine from the balancer bolt.
The following users liked this post:
bluzrocker (01-16-2017)
#4
Race Director
Member Since: Mar 2009
Location: Canada's capital
Posts: 19,777
Received 4,583 Likes
on
2,157 Posts
2020 Corvette of the Year Finalist (appearance mods)
C1 of Year Finalist (appearance mods) 2019
If you rocked the car to get on TDC on the timing marks you have lost your reference point. The last car I did this on I put a piece of tape over the spark plug hole after cleaning it well and rotated the engine until the tape blew off with an audible pop. Brought the balancer the rest of the way to rest on TDC and installed the distributor. An extra pair of hands can also help with using a finger over the plug hole while you turn the engine from the balancer bolt.
The following 2 users liked this post by Kerrmudgeon:
bluzrocker (01-16-2017),
ohiovet (01-17-2017)
#5
Drifting
Thread Starter
remote starter button switch
found one...next question...can you tell me where to hook it up pls?
i did find one in my old tool box but don't really have a sound Idea how to hook it up...I have new wiring on a 67 BB and don't want to make a mistake a regret it for assuming I know the correct way
i did find one in my old tool box but don't really have a sound Idea how to hook it up...I have new wiring on a 67 BB and don't want to make a mistake a regret it for assuming I know the correct way
Last edited by bluzrocker; 01-16-2017 at 09:47 PM. Reason: add info
#6
Melting Slicks
Hook one lead on the positive post on your starter solenoid (the big one with the positive battery cable). Hook the other lead on the small post on your solenoid closest to the block. Push your button and the starter will engage and turn the motor over. Put your finger in number one plug hole and you will feel the compression stroke. Keep bumping the starter until you get close to TDC on the balancer, then use front crank bolt or rock the car to get it on the TDC mark.
Just a reminder, you will most likely have to reach down into the distributor hole and rotate the oil pump drive shaft to get it lined up with the bottom of the distributor.
This is really very easy process, it is not rocket science, just do it step by step. Take a paint marker and mark the location of the number one plug wire on your distributor cap and on the distributor casting so you can get the rotor to drop in the cam gear and the oil pump shaft in the correct position. Make sure your vacuum advance can is in the correct orientation so you have sufficient movement without hitting either your ignition shielding or the intake manifold.
This can all be done in less than 5 minutes.
Just a reminder, you will most likely have to reach down into the distributor hole and rotate the oil pump drive shaft to get it lined up with the bottom of the distributor.
This is really very easy process, it is not rocket science, just do it step by step. Take a paint marker and mark the location of the number one plug wire on your distributor cap and on the distributor casting so you can get the rotor to drop in the cam gear and the oil pump shaft in the correct position. Make sure your vacuum advance can is in the correct orientation so you have sufficient movement without hitting either your ignition shielding or the intake manifold.
This can all be done in less than 5 minutes.
The following 2 users liked this post by jrm5657:
bluzrocker (01-16-2017),
Kerrmudgeon (01-17-2017)
#7
Drifting
Thread Starter
distributor install
Thank you very much for the detailed process...I understand everything but ...reach down into the distributor hole and line up the oil pump drive shaft..pls explain further
your explanation was just great
Just went and looked down the distributor hole and see the oil pump drive shaft with straight slot and now see that will have to line up with distributor shaft
Just a reminder, you will most likely have to reach down into the distributor hole and rotate the oil pump drive shaft to get it lined up with the bottom of the distributor.
your explanation was just great
Just went and looked down the distributor hole and see the oil pump drive shaft with straight slot and now see that will have to line up with distributor shaft
Just a reminder, you will most likely have to reach down into the distributor hole and rotate the oil pump drive shaft to get it lined up with the bottom of the distributor.
Hook one lead on the positive post on your starter solenoid (the big one with the positive battery cable). Hook the other lead on the small post on your solenoid closest to the block. Push your button and the starter will engage and turn the motor over. Put your finger in number one plug hole and you will feel the compression stroke. Keep bumping the starter until you get close to TDC on the balancer, then use front crank bolt or rock the car to get it on the TDC mark.
This is really very easy process, it is not rocket science, just do it step by step. Take a paint marker and mark the location of the number one plug wire on your distributor cap and on the distributor casting so you can get the rotor to drop in the cam gear and the oil pump shaft in the correct position. Make sure your vacuum advance can is in the correct orientation so you have sufficient movement without hitting either your ignition shielding or the intake manifold.
This can all be done in less than 5 minutes.
This is really very easy process, it is not rocket science, just do it step by step. Take a paint marker and mark the location of the number one plug wire on your distributor cap and on the distributor casting so you can get the rotor to drop in the cam gear and the oil pump shaft in the correct position. Make sure your vacuum advance can is in the correct orientation so you have sufficient movement without hitting either your ignition shielding or the intake manifold.
This can all be done in less than 5 minutes.
Last edited by bluzrocker; 01-16-2017 at 11:04 PM. Reason: add info
#8
Melting Slicks
I don't have any pictures, but the top of the drive shaft that connects the distributor shaft to the oil pump has a slot in the top of it. I use a flat blade screwdriver that is about 18 inches long, I have to stand on a small stool and with a bright LED light, I look down into the distributor hole and turn the oil pump shaft so the the slot is in a position to line up with the bottom drive on the distributor shaft.
If you don't get the oil pump shaft positioned properly, the distributor will not drop all the way in after it engages the cam gear. The distributor will end up about 3/8" to 1/2" above the intake. If that happens, pull the distributor back out and reach in and adjust the oil pump shaft slightly and try it again.
If you don't get the oil pump shaft positioned properly, the distributor will not drop all the way in after it engages the cam gear. The distributor will end up about 3/8" to 1/2" above the intake. If that happens, pull the distributor back out and reach in and adjust the oil pump shaft slightly and try it again.
The following users liked this post:
bluzrocker (01-16-2017)
#9
Melting Slicks
You can use a long paint stick or screw driver to turn the oil pump. Some will line up the distributor and bump the engine over until the distributor drops in. If you haven't used that method you may want to go with the paint stick.
The following users liked this post:
bluzrocker (01-16-2017)
#10
Drifting
Thread Starter
dizzy install
thanks to all who responded to my basic questions...I have looked down the hole and yes used a small bench and flash light to see whats there and I think I get the idea after the perfect explanations given...
want to thank all for your input.....
my instructions from Lars says set initial timing @ 16* below 900 rpm and will get additional 20* from the distributor for a total of 36*...all in at 2850 rpm ...engine builder set the static @ 6* and this new curved distributor should run much different than originally set up
Thank you again for the advice
want to thank all for your input.....
my instructions from Lars says set initial timing @ 16* below 900 rpm and will get additional 20* from the distributor for a total of 36*...all in at 2850 rpm ...engine builder set the static @ 6* and this new curved distributor should run much different than originally set up
Thank you again for the advice
Last edited by bluzrocker; 01-16-2017 at 11:17 PM.
#11
Melting Slicks
Make sure you have the vacuum advance disconnected and the hose from the carb plugged when setting the initial timing. Once you get the initial timing set at idle, then hook up the vacuum advance and readjust idle screw on your carb to get desired idle speed. You should be good to go if Lars did the distributor!! He is the best.
The following users liked this post:
bluzrocker (01-19-2017)
#12
Drifting
Thread Starter
timing setting
Tx for that last reminder..bout vacuum disconnected and plugged for initial setting
Make sure you have the vacuum advance disconnected and the hose from the carb plugged when setting the initial timing. Once you get the initial timing set at idle, then hook up the vacuum advance and readjust idle screw on your carb to get desired idle speed. You should be good to go if Lars did the distributor!! He is the best.
The following users liked this post:
bluzrocker (01-19-2017)
#14
Le Mans Master
Oil Pump
To make the process even easier,you do not have to line up the oil pump slot and the distributor. Once you are sure of top dead center, drop the distributor down so the rotor is pointing to the number one plug wire and bump the engine over. After one revolution or less, the distributor will drop down. That's it. Of course, bump the engine with the coil wire disconnected. That should get you started so you can fine tune the engine with a timing light. Good luck. Jerry
#15
Safety Car
Member Since: Jan 2006
Location: Smyrna/Vinings, Georgia
Posts: 3,662
Received 358 Likes
on
241 Posts
Best way to drop distributor is find position where it drops in, then walk it one tooth at a time, it will drop down, keep going until in correct position. no turning oil pump, no bumping engine. As far as TDC if passenger valve cover is off, turn engine until #6 valves rock, that is TDC (for #1) Otherwise the whistle (compression)
Last edited by hope2; 01-17-2017 at 09:11 AM.
#16
Drifting
Thread Starter
TDC and Distributor install
Got the new Distributor from Lars....followed his install sheet(very similar to what all you guys said) except wanted me to bring it up on compression stroke on #1 cyl..
and line up balancer line on 12* BTDC on the timing marks on tab.
verify the rotor is pointing @ # 1 plug wire on the distributor cap.....then with vacuum disconnected set timing @ 16* BTDC...said the 16-18* was important setting ..but the total advance of 36* is the dominate factor...
so my timing tab only goes to 16*...so Ill have to measure the circumference of the harmonic balancer with a sewing machine tape measure as accurately as possible( will be hard to do) and divide by 10...that will give you the number in inches...that number you get is the distance to 36* (clock wise) from the front of the dampner ...
[/B]
draw a new line on the dampner to establish a point that represents aprox 36*..then rev engine to 3000 rpm and see if Im getting a total of 36* max advance.....think Ill try timing tape
I super lesson on distributor theory and what all is involved...gotta give him credit for the work he does A++ and explaining to a dummy like me whats going on and how to get ur 427 to run the best.
and line up balancer line on 12* BTDC on the timing marks on tab.
verify the rotor is pointing @ # 1 plug wire on the distributor cap.....then with vacuum disconnected set timing @ 16* BTDC...said the 16-18* was important setting ..but the total advance of 36* is the dominate factor...
so my timing tab only goes to 16*...so Ill have to measure the circumference of the harmonic balancer with a sewing machine tape measure as accurately as possible( will be hard to do) and divide by 10...that will give you the number in inches...that number you get is the distance to 36* (clock wise) from the front of the dampner ...
[/B]
draw a new line on the dampner to establish a point that represents aprox 36*..then rev engine to 3000 rpm and see if Im getting a total of 36* max advance.....think Ill try timing tape
I super lesson on distributor theory and what all is involved...gotta give him credit for the work he does A++ and explaining to a dummy like me whats going on and how to get ur 427 to run the best.
Best way to drop distributor is find position where it drops in, then walk it one tooth at a time, it will drop down, keep going until in correct position. no turning oil pump, no bumping engine. As far as TDC if passenger valve cover is off, turn engine until #6 valves rock, that is TDC (for #1) Otherwise the whistle (compression)
Last edited by bluzrocker; 01-18-2017 at 11:32 AM.
#17
Melting Slicks
Did you get your car running? Hope your new distributor makes it run great. Give us an update, glad you learned a bit about distributors and timing.
The following users liked this post:
bluzrocker (01-19-2017)
The following users liked this post:
bluzrocker (01-19-2017)
#19
Drifting
Thread Starter
Distributor in
From where it was set by the engine builder(@6* BTDC) it was a Bi#%h
to start...now with one slight turn on the key....varooom...no pumping the gas... stumbling at start up....still will need to fine tune timing @ 16* at below 900 rpm....and probably need to adjust the Idle mixture on the center carb....been raining here in buckets and high winds ...so no test drive yet.....
This has been a incredible journey from where it was,,,to where it's at now...ignition timing set up by a pro has a lot to do with soooo many aspects of how it starts ,performs,idles, spark plug condition,when the advance curve come's in,how rapidly it comes in, better mileage,....
so what a lesson for me and couldn't ask for a better analysis, diagnosis,and rebuild for my application.. ...I believe no off the shelf Distributor can properly be the best set up for cars like ours,,,,,they have to be set up for all of the variables ...4 speed V/S automatic,big cam ...mild cam,high rear gear...low rear gear,,,street,strip..
to start...now with one slight turn on the key....varooom...no pumping the gas... stumbling at start up....still will need to fine tune timing @ 16* at below 900 rpm....and probably need to adjust the Idle mixture on the center carb....been raining here in buckets and high winds ...so no test drive yet.....
This has been a incredible journey from where it was,,,to where it's at now...ignition timing set up by a pro has a lot to do with soooo many aspects of how it starts ,performs,idles, spark plug condition,when the advance curve come's in,how rapidly it comes in, better mileage,....
so what a lesson for me and couldn't ask for a better analysis, diagnosis,and rebuild for my application.. ...I believe no off the shelf Distributor can properly be the best set up for cars like ours,,,,,they have to be set up for all of the variables ...4 speed V/S automatic,big cam ...mild cam,high rear gear...low rear gear,,,street,strip..
#20
Tech Contributor
Member Since: Aug 1999
Location: At my Bar drinking and wrenching in Lafayette Colorado
Posts: 13,654
Received 4,925 Likes
on
1,930 Posts
so my timing tab only goes to 16*...so Ill have to measure the circumference of the harmonic balancer with a sewing machine tape measure as accurately as possible( will be hard to do) and divide by 10...that will give you the number in inches...that number you get is the distance to 36* (clock wise) from the front of the dampner ....
Lars
The following users liked this post:
bluzrocker (01-20-2017)