 How to determine EXACTLY where TDC is?, Valve adjustment advice needed |
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| JRust |
 May 10 2010, 08:36 AM
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#21
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914 Guru  Group: Members Posts: 6,309 Joined: 10-January 03 From: Corvallis Oregon Member No.: 129 Region Association: Pacific Northwest 
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QUOTE(realred914 @ May 10 2010, 07:29 AM)  how can you view the rotor when teh car is running? clear cap? He does not mean while the car is running. I have my motor out of the car & am getting ready to install it. A running car means your marks should be failry close. A non running motor may be off alot depending on what you had done? |
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| jimkelly |
May 10 2010, 08:47 AM
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#22
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Delaware USA Group: Members Posts: 4,969 Joined: 5-August 04 From: Delaware, USA Member No.: 2,460 Region Association: MidAtlantic Region |
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| JRust |
May 10 2010, 08:51 AM
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#23
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914 Guru Group: Members Posts: 6,309 Joined: 10-January 03 From: Corvallis Oregon Member No.: 129 Region Association: Pacific Northwest
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What I am not seeing is how I adjust the distributor to get my rotor pointed where it is supposed to be? I have top dead center & have my timing mark in the hole. How do I get my rotor to the right position (IMG:style_emoticons/default/confused24.gif)
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| realred914 |
May 10 2010, 09:50 AM
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#24
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Senior Member Group: Retired Members Posts: 1,086 Joined: 1-April 10 From: california Member No.: 11,541 Region Association: None |
QUOTE(jimkelly @ May 10 2010, 07:47 AM) pic Gawd, that is horribly complicated. just do one pair of valves at a time, it is much easier, no complex order to remember doing it that way for 30 years and I dont need to remeber any special order. simply set at TDC for 1 and adjust both number 1 valves, then rotate to number 2 tdc and do both number 2 valves etc.......... this aint rocket science, keep it simple. and remember you only need to be close to TDC for each adjustment, as teh cam has a rather large non-lobe area. the rotor location verses the one number one position mark on the dizzie case is presicion enough for my eyeball. |
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| realred914 |
May 10 2010, 09:54 AM
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#25
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Senior Member Group: Retired Members Posts: 1,086 Joined: 1-April 10 From: california Member No.: 11,541 Region Association: None |
QUOTE(JRust @ May 10 2010, 07:51 AM) What I am not seeing is how I adjust the distributor to get my rotor pointed where it is supposed to be? I have top dead center & have my timing mark in the hole. How do I get my rotor to the right position (IMG:style_emoticons/default/confused24.gif) if the rotor is in the worng location it may be 180 degree off so remove the dizzie and rotate motor crankshaft one full turn, then put dizzie back it should now have the rotor 180degree moved. if none of these above two posions are correct, then you have the dizzie drive gear in the worn place. for this to be fixxed, you can follow the proceddure in the reapir books for setting up the drive gear. basically you make sure motor is at TDC for #1 (NOT for #3) and set the drive gear in the hole so the dog drive slot is orientated as shown in the pictures most all rebuild books will have. not too difficult to get right, but it is important. |
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| McMark |
May 10 2010, 10:07 AM
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#26
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
QUOTE(JRust @ May 10 2010, 07:51 AM) What I am not seeing is how I adjust the distributor to get my rotor pointed where it is supposed to be? I have top dead center & have my timing mark in the hole. How do I get my rotor to the right position (IMG:style_emoticons/default/confused24.gif) You don't change the rotor position, you change the orientation of the distributor body. Loosening this with a 10mm wrench will allow the body to rotate. If your distributor drive gear was put in correctly, your distributor is pretty close to right. Probably close enough to start. I can talk your ear off about all the 'philosophy' of distributor orientation at WCR. Attached image(s) 
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| TheCabinetmaker |
May 10 2010, 10:30 AM
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#27
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I drive my car everyday Group: Members Posts: 8,304 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
Dang, there are a lot of different ways to find tdc and adjust valves.
JRust, the two pics on post 17 show the rotor to be pointing toward the # 4 terminal area (I think). The pic of the notch of the van housing shows one of the thick webs. That is not TDC. TDC is about 4 or 5 thin fins to the passenger side of "one" of the thick webs. Either you are not at TDC #1 of compression stroke, or your diz in in wrong. Stick you finger in the #1 plug hole and turn the crank till it blows your finger out the hole. There will be a notch on the edge of the flywheel close to the center line of the crank (assuming your flywheel is so marked). Line up the notch with cl of case (top of engine) and your there. Then make a mark on the bottom of the flywheel. You will have two permanent marks on the flywheel that you can view from the inspection notch on the bottom of the tranni case for future valve adjustments. |
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| JRust |
May 10 2010, 10:30 AM
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#28
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914 Guru Group: Members Posts: 6,309 Joined: 10-January 03 From: Corvallis Oregon Member No.: 129 Region Association: Pacific Northwest
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Okay so I am not off 180 degrees. I am off somewhere in between. My rotor is pointing towards the hole in the fan housing. If I rotated it 180 it would be facing the #3 cylinder?
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| JRust |
May 10 2010, 10:33 AM
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#29
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914 Guru Group: Members Posts: 6,309 Joined: 10-January 03 From: Corvallis Oregon Member No.: 129 Region Association: Pacific Northwest
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QUOTE(vsg914 @ May 10 2010, 09:30 AM) Dang, there are a lot of different ways to find tdc and adjust valves. JRust, the two pics on post 17 show the rotor to be pointing toward the # 4 terminal area (I think). The pic of the notch of the van housing shows one of the thick webs. That is not TDC. TDC is about 4 or 5 thin fins to the passenger side of "one" of the thick webs. Either you are not at TDC #1 of compression stroke, or your diz in in wrong. Stick you finger in the #1 plug hole and turn the crank till it blows your finger out the hole. There will be a notch on the edge of the flywheel close to the center line of the crank (assuming your flywheel is so marked). Line up the notch with cl of case (top of engine) and your there. Then make a mark on the bottom of the flywheel. You will have two permanent marks on the flywheel that you can view from the inspection notch on the bottom of the tranni case for future valve adjustments. You are right. It was a little further turn. I have it on TDC now. |
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| TheCabinetmaker |
May 10 2010, 10:39 AM
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#30
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I drive my car everyday Group: Members Posts: 8,304 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
Cool. I haven't seen a rev liming rotor in many years, so I wasn't sure just where it was pointing.LOL
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| SLITS |
May 10 2010, 10:39 AM
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#31
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"This Utah shit is HARSH!" Group: Benefactors Posts: 13,602 Joined: 22-February 04 From: SoCal Mountains ... Member No.: 1,696 Region Association: None  |
QUOTE(McMark @ May 10 2010, 09:07 AM) QUOTE(JRust @ May 10 2010, 07:51 AM) What I am not seeing is how I adjust the distributor to get my rotor pointed where it is supposed to be? I have top dead center & have my timing mark in the hole. How do I get my rotor to the right position (IMG:style_emoticons/default/confused24.gif) You don't change the rotor position, you change the orientation of the distributor body. Loosening this with a 10mm wrench will allow the body to rotate. If your distributor drive gear was put in correctly, your distributor is pretty close to right. Probably close enough to start. I can talk your ear off about all the 'philosophy' of distributor orientation at WCR. Just to make it more confusing ...... The distributor does not give a crap where it is as long as you have enough "swing" to get the advance you want. What the engine does care is that the #1 high tension wire, pole on cap and the rotor are in alignment plus the firing order is correct. Moving high tension leads can account for a misaligned distributor drive gear. |
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| TheCabinetmaker |
May 10 2010, 10:44 AM
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#32
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I drive my car everyday Group: Members Posts: 8,304 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
I agree with Slits. Seen more than one car with plug wires one off all way round.
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| McMark |
May 10 2010, 10:46 AM
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#33
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
Ignore where your rotor is pointing. It's irrelevant. Really. There is a 'but...' that you don't need to hear about right now.
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| ClayPerrine |
May 10 2010, 10:49 AM
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#34
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Life's been good to me so far..... Group: Admin Posts: 15,597 Joined: 11-September 03 From: Hurst, TX. Member No.: 1,143 Region Association: NineFourteenerVille
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QUOTE(SLITS @ May 10 2010, 11:39 AM) Just to make it more confusing ...... The distributor does not give a crap where it is as long as you have enough "swing" to get the advance you want. What the engine does care is that the #1 high tension wire, pole on cap and the rotor are in alignment plus the firing order is correct. Moving high tension leads can account for a misaligned distributor drive gear. Actually that is not quite true. Some of the beetle and 411 distributors have a 2 degree retard on the point opening for the #3 cylinder. This was done because #3 runs the hottest, and that helps to prevent detonation. So if you get the rotor in wrong, and rearrange the plug wires, it could retard the timing on the wrong cylinder. |
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| McMark |
May 10 2010, 10:50 AM
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#35
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
Your rotor is pointing at the line in the distributor housing (arrow). The motor is at TDC. So you should be close enough to start it, then you need to adjust the timing while the motor is running with a timing light.
Your spark plug wires should connect into the cap as illustrated. Attached image(s) 
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| underthetire |
May 10 2010, 10:51 AM
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#36
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914 Guru Group: Members Posts: 5,062 Joined: 7-October 08 From: Brentwood Member No.: 9,623 Region Association: Northern California |
One way to find TDC on # 1 is remove a plug, place finger over hole, turn motor until you start to feel air pressure, then line up the timing mark. My old timer ( he's turning 50 this month (IMG:style_emoticons/default/happy11.gif) ) neighbor showed me that.
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| TheCabinetmaker |
May 10 2010, 11:40 AM
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#37
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I drive my car everyday Group: Members Posts: 8,304 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
QUOTE(underthetire @ May 10 2010, 11:51 AM) One way to find TDC on # 1 is remove a plug, place finger over hole, turn motor until you start to feel air pressure, then line up the timing mark. My old timer ( he's turning 50 this month (IMG:style_emoticons/default/happy11.gif) ) neighbor showed me that. I could have sworn that was exactly what I said (IMG:style_emoticons/default/confused24.gif) |
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| JRust |
May 10 2010, 12:21 PM
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#38
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914 Guru Group: Members Posts: 6,309 Joined: 10-January 03 From: Corvallis Oregon Member No.: 129 Region Association: Pacific Northwest
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QUOTE(McMark @ May 10 2010, 09:50 AM) Your rotor is pointing at the line in the distributor housing (arrow). The motor is at TDC. So you should be close enough to start it, then you need to adjust the timing while the motor is running with a timing light. Your spark plug wires should connect into the cap as illustrated. AHHH! (IMG:style_emoticons/default/pray.gif) Now that I understand. I was thinking way to much about the rotor. As long as I have where its pointing as my #1 for the firing order. Got it thanks guys. I knew it wasn't as dificult as I was making it (IMG:style_emoticons/default/dry.gif) . Whats with the rev limiting rotor? Any benefits to that over a stock one? I knew it was a different one but didn't know much about it. |
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| McMark |
May 10 2010, 01:01 PM
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#39
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
The rev-limiting rotor has a weight that will disconnect the ignition when a certain RPM is reached.
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| ClayPerrine |
May 10 2010, 02:10 PM
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#40
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Life's been good to me so far..... Group: Admin Posts: 15,597 Joined: 11-September 03 From: Hurst, TX. Member No.: 1,143 Region Association: NineFourteenerVille
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QUOTE(JRust @ May 10 2010, 01:21 PM) Whats with the rev limiting rotor? Any benefits to that over a stock one? I knew it was a different one but didn't know much about it. It prevents testosterone induced brain fade from damaging your motor. |
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