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I am admitting a bonehead move here so everyone else please don't chime in just to tell me I am an idiot. I know that! I would appreciate any constructive feedback/answers.

I had a bear of a time getting the crankshaft bolt off, even with all the right tools. I was so exhausted and exasperated (exhausperated?) when I finally got it off that when I got to removing the timing belt I did not make sure that the three markers (crankshaft and two cam pulleys) were aligned with their "marks". They were all just a bit off to the right so I am 99% sure that I have them correctly positioned, i.e. the notches are all lined up with the marks, but given that the crankshaft rotates twice for each rotation of the cam pulleys I could be one crankshaft rotation off.

I could obviously finish putting it together, start the engine and see if I destroy it, LOL, but that is obviously NOT desirable. Is there ANY way to tell that I have them in sync? If I am one rotation off and turn the whole system (I have the belt on) manually by turning the crankshaft bolt, would I be able to feel the interference between the cylinder heads and the valves? I would think so but I would like the opinion of some people that are more informed than I am.

EDIT 2007 EX J-series engine

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  • Welcome to Motor Vehicle Maintenance & Repair! What year is your Odyssey? I assume it's the V6 (J35) engine?
    – Pᴀᴜʟsᴛᴇʀ2 ♦
    Sep 7, 2018 at 14:38
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    Are you kidding me? We’ve all made bonehead moves. That’s how we learn.
    – zipzit
    Sep 7, 2018 at 14:43
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    @zipzit - But hopefully we figure out those bonehead moves before they lunch the engine! :o)
    – Pᴀᴜʟsᴛᴇʀ2 ♦
    Sep 7, 2018 at 17:12
  • @zipzit, thanks for soft pat on the head, LOL! I take the same approach when answering questions on other stackexchange boards.
    – Andrew Steitz
    Sep 7, 2018 at 17:12
  • @Pᴀᴜʟsᴛᴇʀ2, exactly, that's why I came here!
    – Andrew Steitz
    Sep 7, 2018 at 17:15

1 Answer 1

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Simple engine dynamics of a 4-stroke engine dictates as long as the timing marks are aligned for the engine, it will take two complete rotations of the crankshaft for things to be aligned again. As long as the marks are aligned in one of the two rotations, there is no issue. The crank position indicator shows when the #1 piston is at top dead center (TDC). It doesn't care if it's at TDC between the compression/power strokes or between the exhaust/intake strokes.

For reference, here's an image of how the timing marks should align on the J35 :

enter image description here

NOTE: You probably won't have the marks with white on them. This is just to show you what to look for.

To double check to ensure there's no issues, turn the crank a full 720° and recheck your timing marks. Stop the rotation if there is any resistance if you have the spark plugs out. If you still have the spark plugs in, just turn the crank by hand and allow the pressure to bleed off during the compression stroke on each cylinder. If there's major resistance, don't force anything. In either case if you come to a stoppage, recheck your timing marks.

I wrote a complete article on how to change the timing belt on the J35 engine, if you're so inclined to read it.

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    Thank you, thank you, thank you! Did not know that it did not care about being TDC between compression/power and exhaust/intake. Upvote. Will "accept" after I start my engine and it doesn't self-destruct, LOL. Will also do the suggested 720 crank and recheck. Plugs are not out so the resistance was a serious pain when trying to rotate everything back to TDC. Although I am already in the re-assembly stage I will definitely read your article before I continue to make sure I did not miss anything.
    – Andrew Steitz
    Sep 7, 2018 at 17:01
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    Some cam pulleys have several marks, line up the one labeled 1. Its in the picture, just dont want you to miss that part.
    – Moab
    Sep 7, 2018 at 22:34
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    @Moab - Exactly right and why the arrow is pointing at it..
    – Pᴀᴜʟsᴛᴇʀ2 ♦
    Sep 7, 2018 at 23:51
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    One comment: generally you can see at least one cylinder’s cam lobes thru the oil fill port. There may well be times you want to verify cam shaft is somewhat aligned to the crankshaft before you start spinning things into position. You never want to hard jam a valve into a piston. Be careful. Go slow.
    – zipzit
    Sep 9, 2018 at 1:54
  • @zipzit, not sure I fully understand. Do have time to look at my followup question mechanics.stackexchange.com/questions/58769/… and let me know if this has anything to do with your comment?
    – Andrew Steitz
    Sep 9, 2018 at 14:00

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