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Author Topic: Finding TDC on 1Z engine  (Read 917 times)

May 13, 2017, 01:49:23 pm

foxfour

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Finding TDC on 1Z engine
« on: May 13, 2017, 01:49:23 pm »
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How to find tdc on my 1z that's mounted on an engine stand without flywheel or bellhousing? 

I don't know if the photo will appear when I post this.



Reply #1May 13, 2017, 02:13:25 pm

vanbcguy

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Re: Finding TDC on 1Z engine
« Reply #1 on: May 13, 2017, 02:13:25 pm »
Hard to do without at least taking out an injector or popping the valve cover. Looks like you're pretty much buttoned up there. Even if you find TDC you won't have a very good reference without a flywheel attached - the crank flange is pretty small.

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Reply #2May 13, 2017, 07:13:56 pm

foxfour

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Re: Finding TDC on 1Z engine
« Reply #2 on: May 13, 2017, 07:13:56 pm »
Thanks for the reply. 
My thoughts on this were to do as you said, remove the #1 injector, put a dowel rod in the hole and rotate the engine until the piston is at the top of the cylinder, then replace the dowel rod with a gauge, more back and forth rotation until I'm at a ballpark tdc.  It might be close enough for me to move forward.
Joe

Reply #3May 13, 2017, 08:48:24 pm

libbydiesel

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Re: Finding TDC on 1Z engine
« Reply #3 on: May 13, 2017, 08:48:24 pm »
I have precisely found TDC a couple times on engines by using a tight fitting small ID hose in one of the glow plug or injector holes.  Run the other end of the hose into a jar with some water in it.  Start rotating the engine slowly CW.  If water starts getting sucked into the hose (as opposed to air bubbles being pushed out) then stop, drain the water back out and rotate the crank 180 with the hose out of the water.  Rotate CW slowly while closely watching the bubbles leaving the hose.  At a certain point, the air will stop being pushed out and the water will start being pulled in.  That precise moment is TDC.  It is easiest with a second person, one watching the hose/bubbles and one rotating the crank. 
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Reply #4May 14, 2017, 10:57:50 am

masterbeavis

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Re: Finding TDC on 1Z engine
« Reply #4 on: May 14, 2017, 10:57:50 am »
I can't see the pic, but why are you wanting to find TDC?  Is your timing not fully dialed in?
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Reply #5May 14, 2017, 11:37:47 am

foxfour

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Re: Finding TDC on 1Z engine
« Reply #5 on: May 14, 2017, 11:37:47 am »
Libbydiesel - brilliant!  A super straightforward method.  I really like it.  Thank you very much.  Joe

Masterbeavis - the photo didn't post.  Photobucket doesn't give me, or I can't locate, the option to post IMG at forums.  Maybe it's a windows xp issue.

I need tdc as a baseline for when I remove my present electronic injection pump and install my mechanical injection pump (lr300tdi).

Reply #6May 14, 2017, 02:45:40 pm

ORCoaster

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Re: Finding TDC on 1Z engine
« Reply #6 on: May 14, 2017, 02:45:40 pm »
Foxfour, In Photobucket you just copy the link for the picture and insert it into your message.  There are options for how it will display, either as a picture on the forum or a link that we can click and be taken to your Photobucket place.  That needs to be public access in order to work.
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Reply #7May 14, 2017, 03:10:36 pm

foxfour

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Re: Finding TDC on 1Z engine
« Reply #7 on: May 14, 2017, 03:10:36 pm »


I copy/pasted the IMG into the body of this message, and it worked!  Until now, I've been using the image icon on this site to no avail.  Thanks for the very helpful tip.
Joe

 

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