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easy TDC

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Old Jan 12, 2009 | 11:56 AM
  #1  
DupermanDave's Avatar
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From: Northern Colorado :-(
easy TDC

Is there ane asy way to tell if the engine is at TDC without removing things like spark plugs and the head?

I'm going to do my valve lashes in a few days and want to know how to confirm it's at TDC.

The reason I ask here is because I just want to be positive, as I'll have no help on this project and my confidence is really low at this point (even though I put the head on and engine back together by myself after a head gasket job, I'm still new to engines)

I know I can always remove spark plug number one and poke a screwdriver in there, but is there an easier way?
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Old Jan 12, 2009 | 12:11 PM
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From: Temecula Valley, CA
pull the valve cover... set crank to TDC... adjust all the valves that are loose...
rotate crank 1 turn to TDC again... adjust all the valves that are loose.
Done.
(hint- valves that were tight at one TDC will be loose at the next, and vice versa)

Last edited by abecedarian; Jan 12, 2009 at 12:12 PM.
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Old Jan 12, 2009 | 12:27 PM
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From: Temecula Valley, CA
... or ...
pull valve cover, set to tdc. both valves on cyl 1 or both valves on cyl 4 will be loose so adjust whichever is loose... turn the crank 1/2 turn, adjust the next in firing order, turn 1/2, adjust next in firing order, turn 1/2, adjust next in firing order... done.
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Old Jan 12, 2009 | 12:33 PM
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From: DFW, Texas!
Originally Posted by DupermanDave
Is there ane asy way to tell if the engine is at TDC without removing things like spark plugs and the head?
*boggle*

Pulling the #1 plug is about the easiest thing you can do to determine TDC.
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Old Jan 12, 2009 | 12:38 PM
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From: Northern Colorado :-(
Originally Posted by Windsor
*boggle*

Pulling the #1 plug is about the easiest thing you can do to determine TDC.
Eh, didn't want to burn myself anymore, lol. I know its best to do valve lashing when the engine is warmed up. I've still got blisters from the last project i did.

Thanks guys. Much appreciated.
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Old Jan 12, 2009 | 12:40 PM
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From: Temecula Valley, CA
If you adjust them to a tight .007 intake and tight .011 exhaust you should be fine when warmed up.
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Old Jan 12, 2009 | 01:41 PM
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From: DFW, Texas!
Originally Posted by DupermanDave
Eh, didn't want to burn myself anymore, lol. I know its best to do valve lashing when the engine is warmed up. I've still got blisters from the last project i did.

Thanks guys. Much appreciated.
Put the little rubber "washer" back in your plug socket so that you don't need to get yer fingers that close to warm parts.
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Old Jan 12, 2009 | 03:33 PM
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cant u just manually crank the flywheel til it lines up with the notch at number 5. It's what it said in the manual...
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Old Jan 12, 2009 | 03:49 PM
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There is a "key" for the crank gears, if that key is up meaning if you are looking straight at the motor and the key is @ 12:00 you are tdoc
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Old Jan 12, 2009 | 04:41 PM
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From: Northern Colorado :-(
Originally Posted by 22REw/HP
There is a "key" for the crank gears, if that key is up meaning if you are looking straight at the motor and the key is @ 12:00 you are tdoc
the "key" being the little notch or hole in the top of the crank pully? That's what we went by last time, I was unsure if this was TDC for cylinder one or TDC for another cylinder as well and you just had to keep rotating until this "key" and cylinder one matched.
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Old Jan 12, 2009 | 04:52 PM
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Its so easy, just put you finger in the #1 spark plug, Rotate the crankshaft till you feel the air come out of the #1 sparkplug and have the notch at 0.
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Old Jan 12, 2009 | 05:54 PM
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From: Northern Colorado :-(
Originally Posted by 874runnersr5
Its so easy, just put you finger in the #1 spark plug, Rotate the crankshaft till you feel the air come out of the #1 sparkplug and have the notch at 0.
its hard being under the truck turning the crankshaft bolt and having your finger in the spark plug hole at the same time.
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Old Jan 12, 2009 | 06:01 PM
  #13  
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get a helping hand then, its the easiest way to get tdc this way.
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Old Jan 12, 2009 | 07:30 PM
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From: LA
put a piece of celophane lightly in spark plug 1...

when it blows out and ur at 0, ur at TDC
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Old Jan 13, 2009 | 07:20 AM
  #15  
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Originally Posted by 874runnersr5
get a helping hand then, its the easiest way to get tdc this way.
Little brothers are great! Let them burn the snot out of their fingers.
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Old Jan 13, 2009 | 08:14 AM
  #16  
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Just look at the rocker arm and cam. When the cam is not pushing against the rocker arm, you're at TDC.
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Old Jan 13, 2009 | 08:22 AM
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I don't understand.....all the little tips? Crank mark at zero = TDC. Compression stroke = #1 and #4 valves will be loose. If not, you're on the exhaust stroke. Either way, if at zero, you're at TDC.

Like Abe said.....it's pretty simple.
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Old Jan 13, 2009 | 08:31 AM
  #18  
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From: Northern Colorado :-(
Originally Posted by thook
Crank mark at zero = TDC. Compression stroke = #1 and #4 valves will be loose. If not, you're on the exhaust stroke. Either way, if at zero, you're at TDC.
That's pretty much all i needed. I was just curious if there was any other way to see without removing the head or spark plugs, but I guess not.
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Old Jan 13, 2009 | 08:38 AM
  #19  
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From: NW Ark on wooded ten acres...Ozarks at large!
You never have to remove the head........unless you mean valve cover? Even then, like I said, if at zero.....

To verify compression or exhaust stroke, you can pull the dist. cap and check the rotor position. It should be at the #1 spark terminal on compression. 180* opposite that on the exhaust. This way you don't have to pull the valve cover, but it's moot because the cover has to come off anyway to adjust the valves.

You don't "have" to pull the plugs. But, it does make it easier to crank the motor over. I never do, though. I just strong arm the biotch...hehe. = breaker bar w/19mm socket from up top reaching down to the crank.
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Old Jan 13, 2009 | 08:40 AM
  #20  
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From: Northern Colorado :-(
Originally Posted by thook
You never have to remove the head........unless you mean valve cover? Even then, like I said, if at zero.....

To verify compression or exhaust stroke, you can pull the dist. cap and check the rotor position. It should be at the #1 spark terminal on compression. 180* opposite that on the exhaust. This way you don't have to pull the valve cover, but it's moot because the cover has to come off anyway to adjust the valves.

You don't "have" to pull the plugs. But, it does make it easier to crank the motor over. I never do, though. I just strong arm the biotch...hehe. = breaker bar w/19mm socket from up top reaching down to the crank.
Bleh. yeah, i meant valve cover. I mistyped "head". I don't know why.
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