I'm the dumbest guy I know. Top dead center...where it is? (1 Viewer)

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I completed a successful auto to 4 speed transmission swap during the early throes of the Covid 19 plandemic. Today I decided it was time to replace the side cover gasket and when trying to set the motor to TDC I discovered I have no idea where it is. Like the jackass I am I forgot to mark the flywheels when I swapped them. I simply bolted the new on one an continued to work away.
No worries about today. I got out the marking pen and made several marks on the distributor before pulling it right where it was so I can line everything back up. For future reference though it would be kind of nice to at least have TDC marked.
Anyone else not embarrassed to admit they have done it? If so, any tips on re-discovering TDC?
 

ntdb

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Your flywheel should have a mark on it without you adding one but note that it can be seen in the window on both the exhaust and compression strokes.
 
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Well I know the flywheel has a bb marker on it. What I'm saying is that mark no longer means anything because it will in all probability be in the TDC location while the engine is in fact nowhere near TDC.
 

cruisermatt

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Well I know the flywheel has a bb marker on it. What I'm saying is that mark no longer means anything because it will in all probability be in the TDC location while the engine is in fact nowhere near TDC.

What? why would the TDC mark not show TDC? Also the BB is the timing mark, the thin scribe line 7 degrees after it is TDC
 

red66toy

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What? why would the TDC mark not show TDC? Also the BB is the timing mark, the thin scribe line 7 degrees after it is TDC
I think he is saying he just bolted up the flywheel not in the same orientation it came off.... so the bb could be 180 degrees off from where it should be?

That being said, look at where the dizzy rotor is pointing and what valves are open based on the FSM to gauge where TDC is as well.
 
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Isn’t the flywheel “keyed” with a dowel pin?
Is this true. Maybe even though I forgot to look at the markings and make sure they were in the same place, the flywheel may have been designed so that it would only mount in correct orientation. That would just be too good to be true for me.

Just find TDC based on rotation. Essentially I will have to mark the flywheel once I discover true TDC.
 

tmxmotorsports

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Damn that's awesome. TDC is always TDC, Saucerman proof. Not many things are these days.
Lol i have a buddy that i have known for many many years i named him f***itupchuck if any one can f*** something up its him no joke.. so yea flywheel only goes on one way drop the distributor in with the line on the flywheel lined up through the little window then set timing to the dot
 

ntdb

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I had the same thought when I went to set my timing. I never thought about the "right" way to put the flywheel on and was very happy to find that it's idiot-proof. Note the extra hole for the pin (not my photo).

1594516057310.png
 
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I bought an old VW cheap just for the turbo diesel motor. PO couldn't make it run. Ok easy. I spent hours trying to time the valves. Not my first VW diesel. Every time when bar ring the motor over valves hit piston. The absolutely only thing it can be is the flywheel not installed correctly. I haven't even looked to see how the flywheel is idiot proofed. If there was a dowel maybe it fell out or someone tossed it. So now I have to pull the oil pan or trans.

Keep in mind on a 4 stroke the distributor can be installed 180 degrees out. #1 cylinder must be TDC compression (not exhaust) stroke. In other words both #1 lifters have play on TDC compression.
 

tmxmotorsports

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To confirm tdc and not 180 out if the valve train haven't been messed with th #6 valves will be tight not loose do you have a fsm all of this info is in there buddy if not i can take some pics of this info and message you the pics so you have it in front of you let me know if you need it.
 
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I got the FSM, just so glad I didn't F up the flywheel install. Once I started the side cover job I didn't even try to set TDC because I thought I messed it up. I even went back to my notes I was using when doing the Trans swap. I had check marks by most everything BUT the check for TDC after installing flywheel was right there on the list and unchecked. I am glad it's fool proof. Usually I have to have something damn-fool proof. Glad to hear when I set my valves I will be able to set TDC and actually count on it.
 

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