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Old 04-10-2020, 01:54 PM   #1
dondb
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Help with TDC

I never worked on the engine since buying my truck a few years back. So i wanted to rebuild my carburetor throw on the new ram horns i have along with exhaust system and new HEI. I want to clean up the intake manifold and replace the gasket while i can get at it. I'm trying to find TDC...here's my issue. When both rockers on #1 cylinder closed my rotor button is pointing to #2 cylinder and the timing mark on the balancer is no where near the mark? The only thing i can think is someone changed the timing chain and was off and just compensated instead of redoing it?? Any help would be appreciated What are my options to remove the distributor do the work and get it back together and running?
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Old 04-10-2020, 03:22 PM   #2
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Re: Help with TDC

https://www.google.com/url?sa=t&rct=...aeFSFGCQrphIIZ
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Old 04-10-2020, 03:25 PM   #3
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Re: Help with TDC

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Originally Posted by dondb View Post
I never worked on the engine since buying my truck a few years back. So i wanted to rebuild my carburetor throw on the new ram horns i have along with exhaust system and new HEI. I want to clean up the intake manifold and replace the gasket while i can get at it. I'm trying to find TDC...here's my issue. When both rockers on #1 cylinder closed my rotor button is pointing to #2 cylinder and the timing mark on the balancer is no where near the mark? The only thing i can think is someone changed the timing chain and was off and just compensated instead of redoing it?? Any help would be appreciated What are my options to remove the distributor do the work and get it back together and running?
When you are no where near how much are you actually talking about? Your rotor should be pointing to #1 cylinder which is the opposite bank or are thinking #3 is #2. Roll it till it points to #1 cylinder and see where it is. Once your valves visually close you are not at TDC yet.
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Old 04-10-2020, 03:31 PM   #4
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Re: Help with TDC

Another reason the timing marks would be off is if the outer ring of the balancer has spun in relation to the inner hub. It is not uncommon for the rubber bonding the two pieces to fail. Most of the time a wobble is noticeable when the engine is running, but not always.
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Old 04-10-2020, 03:35 PM   #5
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Re: Help with TDC

thanks gents. With someone else turning the crank I was able to see the piston come up in the spark plug hole. It did line up on the timing mark to balancer mark. Rotor button was pointing to the #7 piston. At least I know I'm at TDC and will start from there when i install the new HEI.
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Old 04-10-2020, 03:47 PM   #6
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Re: Help with TDC

Make sure your piston is up on the compression stroke. Search Youtube for finding TDC. There are several good ways. One is hold your finger in the spark plug hole, when you feel pressure, it's the compression stroke.
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Old 04-10-2020, 03:55 PM   #7
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Re: Help with TDC

This is a good one too.

https://www.youtube.com/watch?v=O4WRL513Gx4
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Old 04-10-2020, 04:02 PM   #8
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Re: Help with TDC

These were the ones I used and found it to be very easy.

https://www.youtube.com/watch?v=5a2X9mSSlQY

https://www.youtube.com/watch?v=FHX1yXVyIMg
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Old 04-10-2020, 06:56 PM   #9
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Re: Help with TDC

If it’s at tdc, someone probably just dropped the distributor in wherever it went in and corrected it with the firing order if that makes sense. I’ve seen it done this way when the oil pump shaft doesn’t line up and the distributor won’t go in with the rotor pointing to number 1. A long flat screw driver can be used to turn the oil pump shaft to line up the oil pump with the distributor.
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Old 04-10-2020, 07:09 PM   #10
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Re: Help with TDC

If the disty is engaged with cam gear you can’t lose timing and just turn crank with socket until oil pump shaft lines up and drops in
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Old 04-11-2020, 10:04 AM   #11
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Re: Help with TDC

Thanks for all the help
What i got confused with is the dizzy moves once to every two turns of the harmonic balancer. I was under the assumption the dizzy moves by the ignition point on exhaust and then back around to compression. So i would get a compression stroke ( with thumb in spark plug hole) every full dizzy. Once I realized compression happened every full dizzy turn things got clear. Pretty embarrassing....

It's not a pretty sight out in my shop....still dealing with a walking boot after a full ruptured achillies tendon and surgery
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Old 04-11-2020, 10:08 AM   #12
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Re: Help with TDC

It’s a 4 stroke.
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Old 04-11-2020, 10:12 AM   #13
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Re: Help with TDC

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It’s a 4 stroke.
Thanks Dan....was on the phone with your buddy Kevin yesterday getting updated on his truck
He shot me over a picture of his new man cave......It's nicer and bigger then my house!!
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Old 04-11-2020, 10:52 AM   #14
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Re: Help with TDC

You know a Kevin. Started with a simple wiring clean up on his 68 and now has half the truck apart.

His building is awesome and overkill is evident everywhere
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Old 04-11-2020, 02:22 PM   #15
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Re: Help with TDC

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still dealing with a walking boot after a full ruptured achillies tendon and surgery
Argh, that's HORRIBLE - hope you get more mobile soon. Good sign you're in a boot though, that's not a fun injury. Take care!
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Old 04-11-2020, 03:38 PM   #16
dondb
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Re: Help with TDC

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Argh, that's HORRIBLE - hope you get more mobile soon. Good sign you're in a boot though, that's not a fun injury. Take care!
Never new how bad until it happened......it's been 11 weeks only about 3 more months until walking alright....a year to best it will get. From your comment I hope you never experienced it?
Thanks for the well wishes
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Old 04-11-2020, 04:13 PM   #17
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Re: Help with TDC

Here is a resource for all your engine needs:

https://www.crankshaftcoalition.com/...Coalition_Wiki

Hope this helps, getting things better soon.
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