Using same marks to install rebuilt ditsy
Thread Starter
Pro
Joined: Mar 2010
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From: Graham NC
Using same marks to install rebuilt ditsy
Hello,
Can I use same marks on base of ditsy, manifold, where rotor is pointing then send ditsy to be rebuilt and reinstall using same marks? Thanks
Can I use same marks on base of ditsy, manifold, where rotor is pointing then send ditsy to be rebuilt and reinstall using same marks? Thanks
Melting Slicks
Joined: Apr 2001
Posts: 2,030
Likes: 363
From: Lubbock Texas
Be careful with how you mark the distributor. I recently pulled my distributor and disassembled it for internal cleaning and shimming the end play. I carefully marked the intake and distributor with a permanent magic marker. Before I reinstalled, I decided to clean the outside of the distributor housing and completely cleaned off all of my marks. Fortunately, I had taken some photos and, because I had just removed it, still remembered the orientation.
DC
Last edited by DC3; Jun 29, 2013 at 08:17 PM.
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
I do this so I have a rough base line and don't have to take the motor to TDC. I spin the motor till the rotor tip is pointing at the firewall and then put some tape in the approximate direction on the firewall, drop a straight edge between and mark. You can mark the distributor's base relationship to the intake, but like others have said you will likely lose that calibration if they clean the housing.
Best to re-time regardless afterwards.
Best to re-time regardless afterwards.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
No.
Any rotation of the engine will negate any orientation marks on the dizzy. Well, you can put it back in that spot, but it won't guarantee that it will be oriented properly. If the engine was not going to be changed (in any way), then, you could mark the position of the rotor relative to the dist. body AND mark the position of the distributor body to the intake. If you then remove the dizzy exactly the same way you took it out, it SHOULD install properly. But, you never know....
If the engine is rotated at all, just forget any orientation marks. Position the crank at TDC for #1 cylinder (on the 'compression' stroke, not the exhaust stroke), set the dizzy rotor so that the contact is pointing to the cap plug with the #1 wire in it (then put a big strip of duct tape from dizzy body up & over the rotor and back to hold that position), note the orientation of the drive pin in the bottom of the dizzy shaft and use a long screwdriver to rotate the oil pump shaft to approximately the same alignment, and drop the dizzy in. Don't forget that the gear is a helical gear and the dizzy will rotate some as it drops into position. So you have to 'lead' it a bit so that it will be in proper position after it completely drops into place.
And, if you don't get it on the first try, just have fun with "Go Fish!"
Any rotation of the engine will negate any orientation marks on the dizzy. Well, you can put it back in that spot, but it won't guarantee that it will be oriented properly. If the engine was not going to be changed (in any way), then, you could mark the position of the rotor relative to the dist. body AND mark the position of the distributor body to the intake. If you then remove the dizzy exactly the same way you took it out, it SHOULD install properly. But, you never know....
If the engine is rotated at all, just forget any orientation marks. Position the crank at TDC for #1 cylinder (on the 'compression' stroke, not the exhaust stroke), set the dizzy rotor so that the contact is pointing to the cap plug with the #1 wire in it (then put a big strip of duct tape from dizzy body up & over the rotor and back to hold that position), note the orientation of the drive pin in the bottom of the dizzy shaft and use a long screwdriver to rotate the oil pump shaft to approximately the same alignment, and drop the dizzy in. Don't forget that the gear is a helical gear and the dizzy will rotate some as it drops into position. So you have to 'lead' it a bit so that it will be in proper position after it completely drops into place.
And, if you don't get it on the first try, just have fun with "Go Fish!"
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Thread Starter
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Joined: Mar 2010
Posts: 615
Likes: 25
From: Graham NC
Be careful with how you mark the distributor. I recently pulled my distributor and disassembled it for internal cleaning and shimming the end play. I carefully marked the intake and distributor with a permanent magic marker. Before I reinstalled, I decided to clean the outside of the distributor housing and completely cleaned off all of my marks. Fortunately, I had taken some photos and, because I had just removed it, still remembered the orientation.
DC
Thread Starter
Pro
Joined: Mar 2010
Posts: 615
Likes: 25
From: Graham NC
No.
Any rotation of the engine will negate any orientation marks on the dizzy. Well, you can put it back in that spot, but it won't guarantee that it will be oriented properly. If the engine was not going to be changed (in any way), then, you could mark the position of the rotor relative to the dist. body AND mark the position of the distributor body to the intake. If you then remove the dizzy exactly the same way you took it out, it SHOULD install properly. But, you never know....
If the engine is rotated at all, just forget any orientation marks. Position the crank at TDC for #1 cylinder (on the 'compression' stroke, not the exhaust stroke), set the dizzy rotor so that the contact is pointing to the cap plug with the #1 wire in it (then put a big strip of duct tape from dizzy body up & over the rotor and back to hold that position), note the orientation of the drive pin in the bottom of the dizzy shaft and use a long screwdriver to rotate the oil pump shaft to approximately the same alignment, and drop the dizzy in. Don't forget that the gear is a helical gear and the dizzy will rotate some as it drops into position. So you have to 'lead' it a bit so that it will be in proper position after it
completely drops into place.
And, if you don't get it on the first try, just have fun with "Go Fish!"
Any rotation of the engine will negate any orientation marks on the dizzy. Well, you can put it back in that spot, but it won't guarantee that it will be oriented properly. If the engine was not going to be changed (in any way), then, you could mark the position of the rotor relative to the dist. body AND mark the position of the distributor body to the intake. If you then remove the dizzy exactly the same way you took it out, it SHOULD install properly. But, you never know....
If the engine is rotated at all, just forget any orientation marks. Position the crank at TDC for #1 cylinder (on the 'compression' stroke, not the exhaust stroke), set the dizzy rotor so that the contact is pointing to the cap plug with the #1 wire in it (then put a big strip of duct tape from dizzy body up & over the rotor and back to hold that position), note the orientation of the drive pin in the bottom of the dizzy shaft and use a long screwdriver to rotate the oil pump shaft to approximately the same alignment, and drop the dizzy in. Don't forget that the gear is a helical gear and the dizzy will rotate some as it drops into position. So you have to 'lead' it a bit so that it will be in proper position after it
completely drops into place.
And, if you don't get it on the first try, just have fun with "Go Fish!"
Tech Contributor
Joined: Aug 1999
Posts: 14,380
Likes: 6,390
From: At my Bar drinking and wrenching in Lafayette Colorado
You're assuming that the distributor is currently installed and clocked correctly. Most are not. By marking and installing it the same way, you're going to duplicate all errors on the current installation. Just bring the engine up to 12 degrees before TDC on the #1 compression stroke (this will have the rotor pointing towards whatever cap tower you are using as #1 plug wire) and yank the distributor out. If I'm the one doing the rebuild, you'll get a complete installation instruction sheet for re-installing it correctly.
Lars
Lars
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Joined: Mar 2010
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From: Graham NC
You're assuming that the distributor is currently installed and clocked correctly. Most are not. By marking and installing it the same way, you're going to duplicate all errors on the current installation. Just bring the engine up to 12 degrees before TDC on the #1 compression stroke (this will have the rotor pointing towards whatever cap tower you are using as #1 plug wire) and yank the distributor out. If I'm the one doing the rebuild, you'll get a complete installation instruction sheet for re-installing it correctly.
Lars
Lars
Race Director
Joined: Jan 2000
Posts: 12,399
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From: San Jose CA
No reason to be scared of TDC. It's not a perfect science and you'll be able to correct it after the distributor is installed, as long as you're close. (IE, the rotor tip points roughly towards the #1 cap)
Safety Car
Joined: Jan 2009
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From: anchorage ak
Race Director
Joined: Jul 2001
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I think you'd be better off educating yourself about the mechanics behind the distributor, cam and crankshaft relationship. It's not rocket science and will take all the scary out of the exercise.
Drifting
Joined: Feb 2005
Posts: 1,879
Likes: 38
From: Los Gatos CA
Mike has a point. This is your opportunity to learn how to do it. You will feel great satisfaction after it's done, and done right. Go for it. Oh yeah, all these gurus, including Mike and Lars, were not exactly stabbing distributors out of the cradle...
Tech Contributor
Joined: Aug 1999
Posts: 14,380
Likes: 6,390
From: At my Bar drinking and wrenching in Lafayette Colorado
Lars
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Joined: Mar 2010
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From: Graham NC
I'm baffled... what's difficult or scary about bringing the engine up on TDC? Being timed and dwelled correctly now is meaningless and irrelevant - you're going to have to re-time it after a distributor removal/rebuild no matter how well you mark it, and the dwell is going to be re-set anyway.
Lars
Lars
Drifting
Joined: Feb 2005
Posts: 1,879
Likes: 38
From: Los Gatos CA
TDC for Dummies:
1) Pull #1 spark plug, which is engine front, driver side..
2) Hold finger over spark plug hole.
3) Have wifey click key (small clicks, on and off), you will feel pressure against finger.
4) Stop before damper mark approaches zero mark on timing tab.
Easy money; even a programmer can do it!
1) Pull #1 spark plug, which is engine front, driver side..
2) Hold finger over spark plug hole.
3) Have wifey click key (small clicks, on and off), you will feel pressure against finger.
4) Stop before damper mark approaches zero mark on timing tab.
Easy money; even a programmer can do it!
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
That, of course, assumes that the timing mark and indicator on the engine are precisely correct, doesn't it.
Ooops! Another fly in the ointment. Need to know how to verify the positioning of those little items to start....
Ooops! Another fly in the ointment. Need to know how to verify the positioning of those little items to start....